From 7f9274035bad30980e03574c315904ab7a85fe83 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Konstantin=20K=C3=A4fer?= <mail@kkaefer.com>
Date: Tue, 2 Apr 2019 14:11:37 +0200
Subject: [core] refactor program object creation

---
 bin/render.cpp                                     |  2 +
 cmake/test.cmake                                   |  1 +
 cmake/vendor.cmake                                 |  2 +-
 include/mbgl/gfx/backend.hpp                       | 44 ++++++++++++++++++++++
 include/mbgl/gfx/renderer_backend.hpp              |  5 +++
 include/mbgl/gl/renderer_backend.hpp               |  3 --
 platform/android/src/android_renderer_backend.cpp  |  2 +-
 .../default/include/mbgl/gfx/headless_backend.hpp  |  9 ++++-
 .../default/src/mbgl/gfx/headless_frontend.cpp     |  6 +--
 platform/default/src/mbgl/gl/headless_backend.cpp  | 12 +++---
 platform/glfw/glfw_backend.hpp                     |  7 ++++
 platform/glfw/glfw_gl_backend.cpp                  | 12 ++++++
 platform/glfw/glfw_view.cpp                        |  9 ++++-
 platform/glfw/glfw_view.hpp                        |  2 +-
 platform/glfw/main.cpp                             |  2 +
 platform/node/src/node_mapbox_gl_native.cpp        | 13 +++++++
 scripts/generate-shaders.js                        |  4 +-
 src/core-files.json                                |  2 +-
 src/mbgl/gfx/context.hpp                           | 14 +++----
 src/mbgl/gfx/context_impl.hpp                      | 23 -----------
 src/mbgl/gfx/types.hpp                             |  4 --
 src/mbgl/gl/context.cpp                            |  2 +-
 src/mbgl/gl/renderer_backend.cpp                   | 32 +++++++---------
 src/mbgl/programs/background_program.cpp           |  4 --
 src/mbgl/programs/circle_program.cpp               |  3 --
 src/mbgl/programs/clipping_mask_program.cpp        |  3 --
 src/mbgl/programs/collision_box_program.cpp        |  4 --
 src/mbgl/programs/debug_program.cpp                |  3 --
 src/mbgl/programs/fill_extrusion_program.cpp       |  4 --
 src/mbgl/programs/fill_program.cpp                 |  6 ---
 src/mbgl/programs/gl/background.cpp                |  4 +-
 src/mbgl/programs/gl/background_pattern.cpp        |  4 +-
 src/mbgl/programs/gl/circle.cpp                    |  4 +-
 src/mbgl/programs/gl/clipping_mask.cpp             |  4 +-
 src/mbgl/programs/gl/collision_box.cpp             |  4 +-
 src/mbgl/programs/gl/collision_circle.cpp          |  4 +-
 src/mbgl/programs/gl/debug.cpp                     |  4 +-
 src/mbgl/programs/gl/fill.cpp                      |  4 +-
 src/mbgl/programs/gl/fill_extrusion.cpp            |  4 +-
 src/mbgl/programs/gl/fill_extrusion_pattern.cpp    |  4 +-
 src/mbgl/programs/gl/fill_outline.cpp              |  4 +-
 src/mbgl/programs/gl/fill_outline_pattern.cpp      |  4 +-
 src/mbgl/programs/gl/fill_pattern.cpp              |  4 +-
 src/mbgl/programs/gl/heatmap.cpp                   |  4 +-
 src/mbgl/programs/gl/heatmap_texture.cpp           |  4 +-
 src/mbgl/programs/gl/hillshade.cpp                 |  4 +-
 src/mbgl/programs/gl/hillshade_prepare.cpp         |  4 +-
 src/mbgl/programs/gl/line.cpp                      |  4 +-
 src/mbgl/programs/gl/line_gradient.cpp             |  4 +-
 src/mbgl/programs/gl/line_pattern.cpp              |  4 +-
 src/mbgl/programs/gl/line_sdf.cpp                  |  4 +-
 src/mbgl/programs/gl/raster.cpp                    |  4 +-
 src/mbgl/programs/gl/symbol_icon.cpp               |  4 +-
 src/mbgl/programs/gl/symbol_sdf_icon.cpp           |  4 +-
 src/mbgl/programs/gl/symbol_sdf_text.cpp           |  4 +-
 src/mbgl/programs/heatmap_program.cpp              |  3 --
 src/mbgl/programs/heatmap_texture_program.cpp      |  3 --
 src/mbgl/programs/hillshade_prepare_program.cpp    |  3 --
 src/mbgl/programs/hillshade_program.cpp            |  3 --
 src/mbgl/programs/line_program.cpp                 |  6 ---
 src/mbgl/programs/raster_program.cpp               |  3 --
 src/mbgl/programs/symbol_program.cpp               |  5 ---
 test/api/custom_layer.test.cpp                     |  4 ++
 test/gl/context.test.cpp                           |  4 ++
 test/map/map.test.cpp                              |  4 ++
 test/src/mbgl/test/test.cpp                        |  9 +++++
 test/util/offscreen_texture.test.cpp               |  8 ++++
 67 files changed, 216 insertions(+), 178 deletions(-)
 create mode 100644 include/mbgl/gfx/backend.hpp
 delete mode 100644 src/mbgl/gfx/context_impl.hpp

diff --git a/bin/render.cpp b/bin/render.cpp
index a29ecdf08a..85231c8cba 100644
--- a/bin/render.cpp
+++ b/bin/render.cpp
@@ -4,6 +4,7 @@
 #include <mbgl/util/run_loop.hpp>
 #include <mbgl/util/default_styles.hpp>
 
+#include <mbgl/gfx/backend.hpp>
 #include <mbgl/gfx/headless_frontend.hpp>
 #include <mbgl/style/style.hpp>
 
@@ -17,6 +18,7 @@ int main(int argc, char *argv[]) {
     args::ArgumentParser argumentParser("Mapbox GL render tool");
     args::HelpFlag helpFlag(argumentParser, "help", "Display this help menu", {"help"});
 
+    args::ValueFlag<std::string> backendValue(argumentParser, "Backend", "Rendering backend", {"backend"});
     args::ValueFlag<std::string> tokenValue(argumentParser, "key", "Mapbox access token", {'t', "token"});
     args::ValueFlag<std::string> styleValue(argumentParser, "URL", "Map stylesheet", {'s', "style"});
     args::ValueFlag<std::string> outputValue(argumentParser, "file", "Output file name", {'o', "output"});
diff --git a/cmake/test.cmake b/cmake/test.cmake
index 0614270089..16dc10f93d 100644
--- a/cmake/test.cmake
+++ b/cmake/test.cmake
@@ -26,6 +26,7 @@ target_include_directories(mbgl-test
 
 target_link_libraries(mbgl-test PRIVATE
     gtest
+    args
     mbgl-core
     shelf-pack-cpp
     unique_resource
diff --git a/cmake/vendor.cmake b/cmake/vendor.cmake
index 7aac53e4cb..0b2deeb552 100644
--- a/cmake/vendor.cmake
+++ b/cmake/vendor.cmake
@@ -27,8 +27,8 @@ include(${CMAKE_SOURCE_DIR}/vendor/unique_resource.cmake)
 include(${CMAKE_SOURCE_DIR}/vendor/variant.cmake)
 include(${CMAKE_SOURCE_DIR}/vendor/vector-tile.cmake)
 include(${CMAKE_SOURCE_DIR}/vendor/wagyu.cmake)
+include(${CMAKE_SOURCE_DIR}/vendor/args.cmake)
 
 if(MBGL_PLATFORM STREQUAL "linux" OR MBGL_PLATFORM STREQUAL "macos")
-    include(${CMAKE_SOURCE_DIR}/vendor/args.cmake)
     include(${CMAKE_SOURCE_DIR}/vendor/glfw.cmake)
 endif()
diff --git a/include/mbgl/gfx/backend.hpp b/include/mbgl/gfx/backend.hpp
new file mode 100644
index 0000000000..eed63dfcba
--- /dev/null
+++ b/include/mbgl/gfx/backend.hpp
@@ -0,0 +1,44 @@
+#pragma once
+
+#include <cstdint>
+#include <cstdlib>
+#include <memory>
+
+namespace mbgl {
+namespace gfx {
+
+class Backend {
+public:
+    enum class Type : uint8_t {
+        OpenGL,
+    };
+
+    static constexpr Type DefaultType = Type::OpenGL;
+
+    static void SetType(const Type value) {
+        if (Value(value) != value) {
+            abort(); // SetType must be called prior to any GetType calls.
+        }
+    }
+
+    static Type GetType() {
+        return Value(DefaultType);
+    }
+
+    template <typename T, typename... Args>
+    static std::unique_ptr<T> Create(Args... args) {
+        return Create<Type::OpenGL, T, Args...>(std::forward<Args>(args)...);
+    }
+
+private:
+    template <Type, typename T, typename... Args>
+    static std::unique_ptr<T> Create(Args...);
+
+    static Type Value(Type value) {
+        static const Type type = value;
+        return type;
+    }
+};
+
+} // namespace gfx
+} // namespace mbgl
diff --git a/include/mbgl/gfx/renderer_backend.hpp b/include/mbgl/gfx/renderer_backend.hpp
index 29f6b43a8f..aa76d7e502 100644
--- a/include/mbgl/gfx/renderer_backend.hpp
+++ b/include/mbgl/gfx/renderer_backend.hpp
@@ -30,6 +30,11 @@ public:
     // Returns the device's context.
     Context& getContext();
 
+    template <typename T>
+    T& getContext() {
+        return static_cast<T&>(getContext());
+    }
+
     bool contextIsShared() const {
         return contextMode == ContextMode::Shared;
     }
diff --git a/include/mbgl/gl/renderer_backend.hpp b/include/mbgl/gl/renderer_backend.hpp
index ba87e4ce4f..cfa28ddaeb 100644
--- a/include/mbgl/gl/renderer_backend.hpp
+++ b/include/mbgl/gl/renderer_backend.hpp
@@ -17,9 +17,6 @@ public:
     RendererBackend(gfx::ContextMode);
     ~RendererBackend() override;
 
-    // Returns the backend's context which manages OpenGL state.
-    Context& getGLContext();
-
     // Called prior to rendering to update the internally assumed OpenGL state.
     virtual void updateAssumedState() = 0;
 
diff --git a/platform/android/src/android_renderer_backend.cpp b/platform/android/src/android_renderer_backend.cpp
index 3fba0b83da..e2d0648385 100755
--- a/platform/android/src/android_renderer_backend.cpp
+++ b/platform/android/src/android_renderer_backend.cpp
@@ -59,7 +59,7 @@ void AndroidRendererBackend::updateAssumedState() {
 
 void AndroidRendererBackend::markContextLost() {
     if (context) {
-        getGLContext().setCleanupOnDestruction(false);
+        getContext<gl::Context>().setCleanupOnDestruction(false);
     }
 }
 
diff --git a/platform/default/include/mbgl/gfx/headless_backend.hpp b/platform/default/include/mbgl/gfx/headless_backend.hpp
index de9283dcdf..325422323a 100644
--- a/platform/default/include/mbgl/gfx/headless_backend.hpp
+++ b/platform/default/include/mbgl/gfx/headless_backend.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <mbgl/gfx/renderable.hpp>
+#include <mbgl/gfx/backend.hpp>
 #include <mbgl/gfx/renderer_backend.hpp>
 #include <mbgl/util/image.hpp>
 
@@ -15,8 +16,12 @@ namespace gfx {
 class HeadlessBackend : public gfx::Renderable {
 public:
     // Factory.
-    static std::unique_ptr<HeadlessBackend> make(Size = { 256, 256 }, gfx::ContextMode = gfx::ContextMode::Unique);
-    
+    static std::unique_ptr<HeadlessBackend>
+    Create(const Size size = { 256, 256 },
+           const gfx::ContextMode contextMode = gfx::ContextMode::Unique) {
+        return Backend::Create<HeadlessBackend, Size, gfx::ContextMode>(size, contextMode);
+    }
+
     virtual PremultipliedImage readStillImage() = 0;
     virtual RendererBackend* getRendererBackend() = 0;
     void setSize(Size);
diff --git a/platform/default/src/mbgl/gfx/headless_frontend.cpp b/platform/default/src/mbgl/gfx/headless_frontend.cpp
index 025abdd87a..0e97c40e49 100644
--- a/platform/default/src/mbgl/gfx/headless_frontend.cpp
+++ b/platform/default/src/mbgl/gfx/headless_frontend.cpp
@@ -23,9 +23,9 @@ HeadlessFrontend::HeadlessFrontend(Size size_,
                                    const gfx::ContextMode contextMode,
                                    const optional<std::string> localFontFamily)
     : size(size_),
-    pixelRatio(pixelRatio_),
-    backend(gfx::HeadlessBackend::make( { static_cast<uint32_t>(size.width * pixelRatio),
-                                          static_cast<uint32_t>(size.height * pixelRatio) }, contextMode)),
+      pixelRatio(pixelRatio_),
+      backend(gfx::HeadlessBackend::Create({ static_cast<uint32_t>(size.width * pixelRatio),
+                                             static_cast<uint32_t>(size.height * pixelRatio) }, contextMode)),
     asyncInvalidate([this] {
         if (renderer && updateParameters) {
             gfx::BackendScope guard { *getBackend() };
diff --git a/platform/default/src/mbgl/gl/headless_backend.cpp b/platform/default/src/mbgl/gl/headless_backend.cpp
index c81952fadc..732e4babae 100644
--- a/platform/default/src/mbgl/gl/headless_backend.cpp
+++ b/platform/default/src/mbgl/gl/headless_backend.cpp
@@ -79,20 +79,22 @@ void HeadlessBackend::updateAssumedState() {
 PremultipliedImage HeadlessBackend::readStillImage() {
     return static_cast<gl::Context&>(getContext()).readFramebuffer<PremultipliedImage>(size);
 }
-    
+
 RendererBackend* HeadlessBackend::getRendererBackend() {
     return this;
 }
 
 } // namespace gl
 
-#ifndef OVERRIDE_HEADLESS_BACKEND_FACTORY
-// Default factory implementation.
-std::unique_ptr<gfx::HeadlessBackend> gfx::HeadlessBackend::make(Size size, gfx::ContextMode contextMode) {
+namespace gfx {
+
+template <>
+std::unique_ptr<gfx::HeadlessBackend>
+Backend::Create<gfx::Backend::Type::OpenGL>(const Size size, const gfx::ContextMode contextMode) {
     return std::make_unique<gl::HeadlessBackend>(size, contextMode);
 }
-#endif
 
+} // namespace gfx
 } // namespace mbgl
 
 
diff --git a/platform/glfw/glfw_backend.hpp b/platform/glfw/glfw_backend.hpp
index 1a2c89ac7a..867e60d79e 100644
--- a/platform/glfw/glfw_backend.hpp
+++ b/platform/glfw/glfw_backend.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <mbgl/util/size.hpp>
+#include <mbgl/gfx/backend.hpp>
 
 namespace mbgl {
 namespace gfx {
@@ -8,6 +9,8 @@ class RendererBackend;
 } // namespace gfx
 } // namespace mbgl
 
+struct GLFWwindow;
+
 class GLFWBackend {
 public:
     explicit GLFWBackend() = default;
@@ -15,6 +18,10 @@ public:
     GLFWBackend& operator=(const GLFWBackend&) = delete;
     virtual ~GLFWBackend() = default;
 
+    static std::unique_ptr<GLFWBackend> Create(GLFWwindow* window, bool capFrameRate) {
+        return mbgl::gfx::Backend::Create<GLFWBackend, GLFWwindow*, bool>(window, capFrameRate);
+    }
+
     virtual mbgl::gfx::RendererBackend& getRendererBackend() = 0;
     virtual mbgl::Size getSize() const = 0;
     virtual void setSize(mbgl::Size) = 0;
diff --git a/platform/glfw/glfw_gl_backend.cpp b/platform/glfw/glfw_gl_backend.cpp
index 4d9d87dd72..d0975fc08f 100644
--- a/platform/glfw/glfw_gl_backend.cpp
+++ b/platform/glfw/glfw_gl_backend.cpp
@@ -72,3 +72,15 @@ void GLFWGLBackend::setSize(const mbgl::Size newSize) {
 void GLFWGLBackend::swap() {
     glfwSwapBuffers(window);
 }
+
+namespace mbgl {
+namespace gfx {
+
+template <>
+std::unique_ptr<GLFWBackend>
+Backend::Create<mbgl::gfx::Backend::Type::OpenGL>(GLFWwindow* window, bool capFrameRate) {
+    return std::make_unique<GLFWGLBackend>(window, capFrameRate);
+}
+
+} // namespace gfx
+} // namespace mbgl
diff --git a/platform/glfw/glfw_view.cpp b/platform/glfw/glfw_view.cpp
index 91e2345bb6..82519e6ac2 100644
--- a/platform/glfw/glfw_view.cpp
+++ b/platform/glfw/glfw_view.cpp
@@ -1,5 +1,5 @@
 #include "glfw_view.hpp"
-#include "glfw_gl_backend.hpp"
+#include "glfw_backend.hpp"
 #include "glfw_renderer_frontend.hpp"
 #include "ny_route.hpp"
 
@@ -17,6 +17,7 @@
 #include <mbgl/util/chrono.hpp>
 #include <mbgl/util/geo.hpp>
 #include <mbgl/renderer/renderer.hpp>
+#include <mbgl/gfx/backend.hpp>
 #include <mbgl/gfx/backend_scope.hpp>
 #include <mbgl/map/camera.hpp>
 
@@ -76,6 +77,10 @@ GLFWView::GLFWView(bool fullscreen_, bool benchmark_)
     glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
 #endif
 
+    if (mbgl::gfx::Backend::GetType() != mbgl::gfx::Backend::Type::OpenGL) {
+        glfwWindowHint(GLFW_CLIENT_API, GLFW_NO_API);
+    }
+
     glfwWindowHint(GLFW_RED_BITS, 8);
     glfwWindowHint(GLFW_GREEN_BITS, 8);
     glfwWindowHint(GLFW_BLUE_BITS, 8);
@@ -100,7 +105,7 @@ GLFWView::GLFWView(bool fullscreen_, bool benchmark_)
 
     glfwGetWindowSize(window, &width, &height);
 
-    backend = std::make_unique<GLFWGLBackend>(window, benchmark);
+    backend = GLFWBackend::Create(window, benchmark);
 
     pixelRatio = static_cast<float>(backend->getSize().width) / width;
 
diff --git a/platform/glfw/glfw_view.hpp b/platform/glfw/glfw_view.hpp
index 1f27bb4421..3322932dde 100644
--- a/platform/glfw/glfw_view.hpp
+++ b/platform/glfw/glfw_view.hpp
@@ -17,7 +17,7 @@ class RendererBackend;
 
 class GLFWView : public mbgl::MapObserver {
 public:
-    GLFWView(bool fullscreen = false, bool benchmark = false);
+    GLFWView(bool fullscreen, bool benchmark);
     ~GLFWView() override;
 
     float getPixelRatio() const;
diff --git a/platform/glfw/main.cpp b/platform/glfw/main.cpp
index 04cff3962a..a5001d1204 100644
--- a/platform/glfw/main.cpp
+++ b/platform/glfw/main.cpp
@@ -2,6 +2,7 @@
 #include "glfw_renderer_frontend.hpp"
 #include "settings_json.hpp"
 
+#include <mbgl/gfx/backend.hpp>
 #include <mbgl/util/default_styles.hpp>
 #include <mbgl/util/logging.hpp>
 #include <mbgl/util/platform.hpp>
@@ -42,6 +43,7 @@ int main(int argc, char *argv[]) {
     args::Flag benchmarkFlag(argumentParser, "benchmark", "Toggle benchmark", {'b', "benchmark"});
     args::Flag offlineFlag(argumentParser, "offline", "Toggle offline", {'o', "offline"});
 
+    args::ValueFlag<std::string> backendValue(argumentParser, "Backend", "Rendering backend", {"backend"});
     args::ValueFlag<std::string> styleValue(argumentParser, "URL", "Map stylesheet", {'s', "style"});
     args::ValueFlag<std::string> cacheDBValue(argumentParser, "file", "Cache database file name", {'c', "cache"});
     args::ValueFlag<double> lonValue(argumentParser, "degrees", "Longitude", {'x', "lon"});
diff --git a/platform/node/src/node_mapbox_gl_native.cpp b/platform/node/src/node_mapbox_gl_native.cpp
index 96e96e4298..9b4437b0aa 100644
--- a/platform/node/src/node_mapbox_gl_native.cpp
+++ b/platform/node/src/node_mapbox_gl_native.cpp
@@ -6,12 +6,23 @@
 #pragma GCC diagnostic pop
 
 #include <mbgl/util/run_loop.hpp>
+#include <mbgl/gfx/backend.hpp>
 
 #include "node_map.hpp"
 #include "node_logging.hpp"
 #include "node_request.hpp"
 #include "node_expression.hpp"
 
+
+void SetBackendType(const Nan::FunctionCallbackInfo<v8::Value>& info) {
+    if (info.Length() < 1 || info[0]->IsUndefined()) {
+        return Nan::ThrowTypeError("Requires a render backend name");
+    }
+
+    const std::string backendName { *Nan::Utf8String(info[0]) };
+    (void)backendName;
+}
+
 void RegisterModule(v8::Local<v8::Object> target, v8::Local<v8::Object> module) {
     // This has the effect of:
     //   a) Ensuring that the static local variable is initialized before any thread contention.
@@ -19,6 +30,8 @@ void RegisterModule(v8::Local<v8::Object> target, v8::Local<v8::Object> module)
     static mbgl::util::RunLoop nodeRunLoop;
     nodeRunLoop.stop();
 
+    Nan::SetMethod(target, "setBackendType", SetBackendType);
+
     node_mbgl::NodeMap::Init(target);
     node_mbgl::NodeRequest::Init();
     node_mbgl::NodeExpression::Init(target);
diff --git a/scripts/generate-shaders.js b/scripts/generate-shaders.js
index 3fe6cafaf6..cb0c945f3c 100755
--- a/scripts/generate-shaders.js
+++ b/scripts/generate-shaders.js
@@ -178,8 +178,8 @@ constexpr const uint8_t ShaderSource<${ShaderName}Program>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<${ShaderName}Program>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<${ShaderName}Program>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<${ShaderName}Program>>(programParameters);
 }
 
diff --git a/src/core-files.json b/src/core-files.json
index 05870661db..eb581f7959 100644
--- a/src/core-files.json
+++ b/src/core-files.json
@@ -321,6 +321,7 @@
         "mbgl/actor/message.hpp": "include/mbgl/actor/message.hpp",
         "mbgl/actor/scheduler.hpp": "include/mbgl/actor/scheduler.hpp",
         "mbgl/annotation/annotation.hpp": "include/mbgl/annotation/annotation.hpp",
+        "mbgl/gfx/backend.hpp": "include/mbgl/gfx/backend.hpp",
         "mbgl/gfx/backend_scope.hpp": "include/mbgl/gfx/backend_scope.hpp",
         "mbgl/gfx/renderable.hpp": "include/mbgl/gfx/renderable.hpp",
         "mbgl/gfx/renderer_backend.hpp": "include/mbgl/gfx/renderer_backend.hpp",
@@ -513,7 +514,6 @@
         "mbgl/gfx/color_mode.hpp": "src/mbgl/gfx/color_mode.hpp",
         "mbgl/gfx/command_encoder.hpp": "src/mbgl/gfx/command_encoder.hpp",
         "mbgl/gfx/context.hpp": "src/mbgl/gfx/context.hpp",
-        "mbgl/gfx/context_impl.hpp": "src/mbgl/gfx/context_impl.hpp",
         "mbgl/gfx/cull_face_mode.hpp": "src/mbgl/gfx/cull_face_mode.hpp",
         "mbgl/gfx/debug_group.hpp": "src/mbgl/gfx/debug_group.hpp",
         "mbgl/gfx/depth_mode.hpp": "src/mbgl/gfx/depth_mode.hpp",
diff --git a/src/mbgl/gfx/context.hpp b/src/mbgl/gfx/context.hpp
index 118df30a26..53cd318642 100644
--- a/src/mbgl/gfx/context.hpp
+++ b/src/mbgl/gfx/context.hpp
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <mbgl/gfx/backend.hpp>
 #include <mbgl/gfx/renderbuffer.hpp>
 #include <mbgl/gfx/command_encoder.hpp>
 #include <mbgl/gfx/draw_scope.hpp>
@@ -17,12 +18,11 @@ class OffscreenTexture;
 
 class Context {
 protected:
-    Context(ContextType type_, uint32_t maximumVertexBindingCount_)
-        : backend(type_), maximumVertexBindingCount(maximumVertexBindingCount_) {
+    Context(uint32_t maximumVertexBindingCount_)
+        : maximumVertexBindingCount(maximumVertexBindingCount_) {
     }
 
 public:
-    const ContextType backend;
     static constexpr const uint32_t minimumRequiredVertexBindingCount = 8;
     const uint32_t maximumVertexBindingCount;
     bool supportsHalfFloatTextures = false;
@@ -80,11 +80,9 @@ protected:
 
 public:
     template <typename Name>
-    std::unique_ptr<Program<Name>> createProgram(const ProgramParameters&);
-
-private:
-    template <typename Backend, typename Name>
-    std::unique_ptr<Program<Name>> createProgram(const ProgramParameters&);
+    std::unique_ptr<Program<Name>> createProgram(const ProgramParameters& programParameters) {
+        return Backend::Create<Program<Name>, const ProgramParameters&>(programParameters);
+    }
 
 public:
     virtual std::unique_ptr<CommandEncoder> createCommandEncoder() = 0;
diff --git a/src/mbgl/gfx/context_impl.hpp b/src/mbgl/gfx/context_impl.hpp
deleted file mode 100644
index 0145535bb3..0000000000
--- a/src/mbgl/gfx/context_impl.hpp
+++ /dev/null
@@ -1,23 +0,0 @@
-#pragma once
-
-#include <mbgl/gfx/context.hpp>
-
-namespace mbgl {
-
-namespace gl {
-class Context;
-} // namespace gl
-
-namespace gfx {
-
-template <typename Name>
-std::unique_ptr<Program<Name>> Context::createProgram(const ProgramParameters& programParameters) {
-    if (backend == ContextType::OpenGL) {
-        return createProgram<gl::Context, Name>(programParameters);
-    }
-    assert(false);
-    return nullptr;
-}
-
-} // namespace gfx
-} // namespace mbgl
diff --git a/src/mbgl/gfx/types.hpp b/src/mbgl/gfx/types.hpp
index 24209c5cc5..cafb2f3f84 100644
--- a/src/mbgl/gfx/types.hpp
+++ b/src/mbgl/gfx/types.hpp
@@ -5,10 +5,6 @@
 namespace mbgl {
 namespace gfx {
 
-enum class ContextType : uint8_t {
-    OpenGL,
-};
-
 enum class PrimitiveType : uint8_t {
     Point,
     Line,
diff --git a/src/mbgl/gl/context.cpp b/src/mbgl/gl/context.cpp
index 436e1f6a61..626e1f4b66 100644
--- a/src/mbgl/gl/context.cpp
+++ b/src/mbgl/gl/context.cpp
@@ -50,7 +50,7 @@ static_assert(underlying_type(UniformDataType::Sampler2D) == GL_SAMPLER_2D, "Ope
 static_assert(underlying_type(UniformDataType::SamplerCube) == GL_SAMPLER_CUBE, "OpenGL type mismatch");
 
 Context::Context(RendererBackend& backend_)
-    : gfx::Context(gfx::ContextType::OpenGL, [] {
+    : gfx::Context([] {
           GLint value;
           MBGL_CHECK_ERROR(glGetIntegerv(GL_MAX_VERTEX_ATTRIBS, &value));
           return value;
diff --git a/src/mbgl/gl/renderer_backend.cpp b/src/mbgl/gl/renderer_backend.cpp
index 9da6ceb589..fe0ca4b5b2 100644
--- a/src/mbgl/gl/renderer_backend.cpp
+++ b/src/mbgl/gl/renderer_backend.cpp
@@ -21,50 +21,46 @@ std::unique_ptr<gfx::Context> RendererBackend::createContext() {
     return std::move(result);
 }
 
-gl::Context& RendererBackend::getGLContext() {
-    return static_cast<gl::Context&>(getContext());
-}
-
 PremultipliedImage RendererBackend::readFramebuffer(const Size& size) {
-    return getGLContext().readFramebuffer<PremultipliedImage>(size);
+    return getContext<gl::Context>().readFramebuffer<PremultipliedImage>(size);
 }
 
 void RendererBackend::assumeFramebufferBinding(const gl::FramebufferID fbo) {
-    getGLContext().bindFramebuffer.setCurrentValue(fbo);
+    getContext<gl::Context>().bindFramebuffer.setCurrentValue(fbo);
     if (fbo != ImplicitFramebufferBinding) {
-        assert(gl::value::BindFramebuffer::Get() == getGLContext().bindFramebuffer.getCurrentValue());
+        assert(gl::value::BindFramebuffer::Get() == getContext<gl::Context>().bindFramebuffer.getCurrentValue());
     }
 }
 
 void RendererBackend::assumeViewport(int32_t x, int32_t y, const Size& size) {
-    getGLContext().viewport.setCurrentValue({ x, y, size });
-    assert(gl::value::Viewport::Get() == getGLContext().viewport.getCurrentValue());
+    getContext<gl::Context>().viewport.setCurrentValue({ x, y, size });
+    assert(gl::value::Viewport::Get() == getContext<gl::Context>().viewport.getCurrentValue());
 }
 
 void RendererBackend::assumeScissorTest(bool enabled) {
-    getGLContext().scissorTest.setCurrentValue(enabled);
-    assert(gl::value::ScissorTest::Get() == getGLContext().scissorTest.getCurrentValue());
+    getContext<gl::Context>().scissorTest.setCurrentValue(enabled);
+    assert(gl::value::ScissorTest::Get() == getContext<gl::Context>().scissorTest.getCurrentValue());
 }
 
 bool RendererBackend::implicitFramebufferBound() {
-    return getGLContext().bindFramebuffer.getCurrentValue() == ImplicitFramebufferBinding;
+    return getContext<gl::Context>().bindFramebuffer.getCurrentValue() == ImplicitFramebufferBinding;
 }
 
 void RendererBackend::setFramebufferBinding(const gl::FramebufferID fbo) {
-    getGLContext().bindFramebuffer = fbo;
+    getContext<gl::Context>().bindFramebuffer = fbo;
     if (fbo != ImplicitFramebufferBinding) {
-        assert(gl::value::BindFramebuffer::Get() == getGLContext().bindFramebuffer.getCurrentValue());
+        assert(gl::value::BindFramebuffer::Get() == getContext<gl::Context>().bindFramebuffer.getCurrentValue());
     }
 }
 
 void RendererBackend::setViewport(int32_t x, int32_t y, const Size& size) {
-    getGLContext().viewport = { x, y, size };
-    assert(gl::value::Viewport::Get() == getGLContext().viewport.getCurrentValue());
+    getContext<gl::Context>().viewport = { x, y, size };
+    assert(gl::value::Viewport::Get() == getContext<gl::Context>().viewport.getCurrentValue());
 }
 
 void RendererBackend::setScissorTest(bool enabled) {
-    getGLContext().scissorTest = enabled;
-    assert(gl::value::ScissorTest::Get() == getGLContext().scissorTest.getCurrentValue());
+    getContext<gl::Context>().scissorTest = enabled;
+    assert(gl::value::ScissorTest::Get() == getContext<gl::Context>().scissorTest.getCurrentValue());
 }
 
 RendererBackend::~RendererBackend() = default;
diff --git a/src/mbgl/programs/background_program.cpp b/src/mbgl/programs/background_program.cpp
index 772d481578..edabce8ee3 100644
--- a/src/mbgl/programs/background_program.cpp
+++ b/src/mbgl/programs/background_program.cpp
@@ -1,5 +1,4 @@
 #include <mbgl/programs/background_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 #include <mbgl/renderer/image_atlas.hpp>
 #include <mbgl/renderer/cross_faded_property_evaluator.hpp>
 #include <mbgl/tile/tile_id.hpp>
@@ -7,9 +6,6 @@
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<BackgroundProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<BackgroundPatternProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 using namespace style;
 
 static_assert(sizeof(BackgroundLayoutVertex) == 4, "expected BackgroundLayoutVertex size");
diff --git a/src/mbgl/programs/circle_program.cpp b/src/mbgl/programs/circle_program.cpp
index 577410d94e..99b47dd5c0 100644
--- a/src/mbgl/programs/circle_program.cpp
+++ b/src/mbgl/programs/circle_program.cpp
@@ -1,10 +1,7 @@
 #include <mbgl/programs/circle_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<CircleProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 static_assert(sizeof(CircleLayoutVertex) == 4, "expected CircleLayoutVertex size");
 
 } // namespace mbgl
diff --git a/src/mbgl/programs/clipping_mask_program.cpp b/src/mbgl/programs/clipping_mask_program.cpp
index 9b1a9ef4fc..aca7605037 100644
--- a/src/mbgl/programs/clipping_mask_program.cpp
+++ b/src/mbgl/programs/clipping_mask_program.cpp
@@ -1,8 +1,5 @@
 #include <mbgl/programs/clipping_mask_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<ClippingMaskProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 } // namespace mbgl
diff --git a/src/mbgl/programs/collision_box_program.cpp b/src/mbgl/programs/collision_box_program.cpp
index 885894526e..584013640e 100644
--- a/src/mbgl/programs/collision_box_program.cpp
+++ b/src/mbgl/programs/collision_box_program.cpp
@@ -1,11 +1,7 @@
 #include <mbgl/programs/collision_box_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<CollisionBoxProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<CollisionCircleProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 static_assert(sizeof(CollisionBoxProgram::LayoutVertex) == 24, "expected CollisionBoxVertex size");
 
 } // namespace mbgl
diff --git a/src/mbgl/programs/debug_program.cpp b/src/mbgl/programs/debug_program.cpp
index 9b8df789e4..3396e74872 100644
--- a/src/mbgl/programs/debug_program.cpp
+++ b/src/mbgl/programs/debug_program.cpp
@@ -1,8 +1,5 @@
 #include <mbgl/programs/debug_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<DebugProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 } // namespace mbgl
diff --git a/src/mbgl/programs/fill_extrusion_program.cpp b/src/mbgl/programs/fill_extrusion_program.cpp
index 09da6931b6..d22e911589 100644
--- a/src/mbgl/programs/fill_extrusion_program.cpp
+++ b/src/mbgl/programs/fill_extrusion_program.cpp
@@ -1,5 +1,4 @@
 #include <mbgl/programs/fill_extrusion_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 #include <mbgl/renderer/image_atlas.hpp>
 #include <mbgl/renderer/cross_faded_property_evaluator.hpp>
 #include <mbgl/tile/tile_id.hpp>
@@ -8,9 +7,6 @@
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<FillExtrusionProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<FillExtrusionPatternProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 using namespace style;
 
 static_assert(sizeof(FillExtrusionLayoutVertex) == 12, "expected FillExtrusionLayoutVertex size");
diff --git a/src/mbgl/programs/fill_program.cpp b/src/mbgl/programs/fill_program.cpp
index 703d61399f..f314fcc597 100644
--- a/src/mbgl/programs/fill_program.cpp
+++ b/src/mbgl/programs/fill_program.cpp
@@ -1,5 +1,4 @@
 #include <mbgl/programs/fill_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 #include <mbgl/renderer/image_atlas.hpp>
 #include <mbgl/renderer/cross_faded_property_evaluator.hpp>
 #include <mbgl/tile/tile_id.hpp>
@@ -7,11 +6,6 @@
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<FillProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<FillPatternProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<FillOutlineProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<FillOutlinePatternProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 using namespace style;
 
 static_assert(sizeof(FillLayoutVertex) == 4, "expected FillLayoutVertex size");
diff --git a/src/mbgl/programs/gl/background.cpp b/src/mbgl/programs/gl/background.cpp
index 78074d670f..f3d2cdfd90 100644
--- a/src/mbgl/programs/gl/background.cpp
+++ b/src/mbgl/programs/gl/background.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<BackgroundProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<BackgroundProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<BackgroundProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<BackgroundProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/background_pattern.cpp b/src/mbgl/programs/gl/background_pattern.cpp
index 04111c7abd..482814cbda 100644
--- a/src/mbgl/programs/gl/background_pattern.cpp
+++ b/src/mbgl/programs/gl/background_pattern.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<BackgroundPatternProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<BackgroundPatternProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<BackgroundPatternProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<BackgroundPatternProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/circle.cpp b/src/mbgl/programs/gl/circle.cpp
index 5cf7eef13c..bd86c0385a 100644
--- a/src/mbgl/programs/gl/circle.cpp
+++ b/src/mbgl/programs/gl/circle.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<CircleProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<CircleProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<CircleProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<CircleProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/clipping_mask.cpp b/src/mbgl/programs/gl/clipping_mask.cpp
index 1b6c7b51c5..2c53bc6070 100644
--- a/src/mbgl/programs/gl/clipping_mask.cpp
+++ b/src/mbgl/programs/gl/clipping_mask.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<ClippingMaskProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<ClippingMaskProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<ClippingMaskProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<ClippingMaskProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/collision_box.cpp b/src/mbgl/programs/gl/collision_box.cpp
index 89c4fe81ae..a3ad030f5c 100644
--- a/src/mbgl/programs/gl/collision_box.cpp
+++ b/src/mbgl/programs/gl/collision_box.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<CollisionBoxProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<CollisionBoxProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<CollisionBoxProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<CollisionBoxProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/collision_circle.cpp b/src/mbgl/programs/gl/collision_circle.cpp
index 96f5d68ce5..3878122f4b 100644
--- a/src/mbgl/programs/gl/collision_circle.cpp
+++ b/src/mbgl/programs/gl/collision_circle.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<CollisionCircleProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<CollisionCircleProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<CollisionCircleProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<CollisionCircleProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/debug.cpp b/src/mbgl/programs/gl/debug.cpp
index 2e5db36dac..9705fc4801 100644
--- a/src/mbgl/programs/gl/debug.cpp
+++ b/src/mbgl/programs/gl/debug.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<DebugProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<DebugProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<DebugProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<DebugProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/fill.cpp b/src/mbgl/programs/gl/fill.cpp
index 7a281c24ba..77c839850b 100644
--- a/src/mbgl/programs/gl/fill.cpp
+++ b/src/mbgl/programs/gl/fill.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<FillProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<FillProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<FillProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<FillProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/fill_extrusion.cpp b/src/mbgl/programs/gl/fill_extrusion.cpp
index d90988070a..87ef4858fc 100644
--- a/src/mbgl/programs/gl/fill_extrusion.cpp
+++ b/src/mbgl/programs/gl/fill_extrusion.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<FillExtrusionProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<FillExtrusionProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<FillExtrusionProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<FillExtrusionProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/fill_extrusion_pattern.cpp b/src/mbgl/programs/gl/fill_extrusion_pattern.cpp
index a6292b9fe1..1d330220e4 100644
--- a/src/mbgl/programs/gl/fill_extrusion_pattern.cpp
+++ b/src/mbgl/programs/gl/fill_extrusion_pattern.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<FillExtrusionPatternProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<FillExtrusionPatternProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<FillExtrusionPatternProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<FillExtrusionPatternProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/fill_outline.cpp b/src/mbgl/programs/gl/fill_outline.cpp
index 82d56710a7..efef689f91 100644
--- a/src/mbgl/programs/gl/fill_outline.cpp
+++ b/src/mbgl/programs/gl/fill_outline.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<FillOutlineProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<FillOutlineProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<FillOutlineProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<FillOutlineProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/fill_outline_pattern.cpp b/src/mbgl/programs/gl/fill_outline_pattern.cpp
index 7709991353..d526d5801d 100644
--- a/src/mbgl/programs/gl/fill_outline_pattern.cpp
+++ b/src/mbgl/programs/gl/fill_outline_pattern.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<FillOutlinePatternProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<FillOutlinePatternProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<FillOutlinePatternProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<FillOutlinePatternProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/fill_pattern.cpp b/src/mbgl/programs/gl/fill_pattern.cpp
index ff4f2045ac..0f62206f99 100644
--- a/src/mbgl/programs/gl/fill_pattern.cpp
+++ b/src/mbgl/programs/gl/fill_pattern.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<FillPatternProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<FillPatternProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<FillPatternProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<FillPatternProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/heatmap.cpp b/src/mbgl/programs/gl/heatmap.cpp
index 7685b568cb..41f804a37b 100644
--- a/src/mbgl/programs/gl/heatmap.cpp
+++ b/src/mbgl/programs/gl/heatmap.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<HeatmapProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<HeatmapProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<HeatmapProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<HeatmapProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/heatmap_texture.cpp b/src/mbgl/programs/gl/heatmap_texture.cpp
index 60ef68597d..a6583bfbb7 100644
--- a/src/mbgl/programs/gl/heatmap_texture.cpp
+++ b/src/mbgl/programs/gl/heatmap_texture.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<HeatmapTextureProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<HeatmapTextureProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<HeatmapTextureProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<HeatmapTextureProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/hillshade.cpp b/src/mbgl/programs/gl/hillshade.cpp
index f0579aaf8c..b0c2c95aa8 100644
--- a/src/mbgl/programs/gl/hillshade.cpp
+++ b/src/mbgl/programs/gl/hillshade.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<HillshadeProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<HillshadeProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<HillshadeProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<HillshadeProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/hillshade_prepare.cpp b/src/mbgl/programs/gl/hillshade_prepare.cpp
index f9cd84ca73..1aef64293b 100644
--- a/src/mbgl/programs/gl/hillshade_prepare.cpp
+++ b/src/mbgl/programs/gl/hillshade_prepare.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<HillshadePrepareProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<HillshadePrepareProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<HillshadePrepareProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<HillshadePrepareProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/line.cpp b/src/mbgl/programs/gl/line.cpp
index 9eea81f69b..58f626bf19 100644
--- a/src/mbgl/programs/gl/line.cpp
+++ b/src/mbgl/programs/gl/line.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<LineProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<LineProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<LineProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<LineProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/line_gradient.cpp b/src/mbgl/programs/gl/line_gradient.cpp
index 4e7ee93b92..c555b09932 100644
--- a/src/mbgl/programs/gl/line_gradient.cpp
+++ b/src/mbgl/programs/gl/line_gradient.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<LineGradientProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<LineGradientProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<LineGradientProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<LineGradientProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/line_pattern.cpp b/src/mbgl/programs/gl/line_pattern.cpp
index 24406abf3b..17ec324c11 100644
--- a/src/mbgl/programs/gl/line_pattern.cpp
+++ b/src/mbgl/programs/gl/line_pattern.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<LinePatternProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<LinePatternProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<LinePatternProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<LinePatternProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/line_sdf.cpp b/src/mbgl/programs/gl/line_sdf.cpp
index aa72823ae7..2d0a5faacd 100644
--- a/src/mbgl/programs/gl/line_sdf.cpp
+++ b/src/mbgl/programs/gl/line_sdf.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<LineSDFProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<LineSDFProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<LineSDFProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<LineSDFProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/raster.cpp b/src/mbgl/programs/gl/raster.cpp
index 98cfade1f5..f6ae3b5bc5 100644
--- a/src/mbgl/programs/gl/raster.cpp
+++ b/src/mbgl/programs/gl/raster.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<RasterProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<RasterProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<RasterProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<RasterProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/symbol_icon.cpp b/src/mbgl/programs/gl/symbol_icon.cpp
index cb896b4160..834bfc16d2 100644
--- a/src/mbgl/programs/gl/symbol_icon.cpp
+++ b/src/mbgl/programs/gl/symbol_icon.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<SymbolIconProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<SymbolIconProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<SymbolIconProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<SymbolIconProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/symbol_sdf_icon.cpp b/src/mbgl/programs/gl/symbol_sdf_icon.cpp
index a25754ffad..2daa1e860d 100644
--- a/src/mbgl/programs/gl/symbol_sdf_icon.cpp
+++ b/src/mbgl/programs/gl/symbol_sdf_icon.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<SymbolSDFIconProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<SymbolSDFIconProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<SymbolSDFIconProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<SymbolSDFIconProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/gl/symbol_sdf_text.cpp b/src/mbgl/programs/gl/symbol_sdf_text.cpp
index 9aec77043b..5750e7730c 100644
--- a/src/mbgl/programs/gl/symbol_sdf_text.cpp
+++ b/src/mbgl/programs/gl/symbol_sdf_text.cpp
@@ -29,8 +29,8 @@ constexpr const uint8_t ShaderSource<SymbolSDFTextProgram>::hash[8];
 namespace gfx {
 
 template <>
-std::unique_ptr<Program<SymbolSDFTextProgram>>
-Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+std::unique_ptr<gfx::Program<SymbolSDFTextProgram>>
+Backend::Create<gfx::Backend::Type::OpenGL>(const ProgramParameters& programParameters) {
     return std::make_unique<gl::Program<SymbolSDFTextProgram>>(programParameters);
 }
 
diff --git a/src/mbgl/programs/heatmap_program.cpp b/src/mbgl/programs/heatmap_program.cpp
index 32c30ea313..67f84fbd52 100644
--- a/src/mbgl/programs/heatmap_program.cpp
+++ b/src/mbgl/programs/heatmap_program.cpp
@@ -1,10 +1,7 @@
 #include <mbgl/programs/heatmap_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<HeatmapProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 static_assert(sizeof(HeatmapLayoutVertex) == 4, "expected HeatmapLayoutVertex size");
 
 } // namespace mbgl
diff --git a/src/mbgl/programs/heatmap_texture_program.cpp b/src/mbgl/programs/heatmap_texture_program.cpp
index 04c5ff56a7..3b0e24eab8 100644
--- a/src/mbgl/programs/heatmap_texture_program.cpp
+++ b/src/mbgl/programs/heatmap_texture_program.cpp
@@ -1,10 +1,7 @@
 #include <mbgl/programs/heatmap_texture_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<HeatmapTextureProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 static_assert(sizeof(HeatmapTextureLayoutVertex) == 4, "expected HeatmapTextureLayoutVertex size");
 
 } // namespace mbgl
diff --git a/src/mbgl/programs/hillshade_prepare_program.cpp b/src/mbgl/programs/hillshade_prepare_program.cpp
index 5bbac9eaec..0c0446d3f5 100644
--- a/src/mbgl/programs/hillshade_prepare_program.cpp
+++ b/src/mbgl/programs/hillshade_prepare_program.cpp
@@ -1,10 +1,7 @@
 #include <mbgl/programs/hillshade_prepare_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<HillshadePrepareProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 static_assert(sizeof(HillshadePrepareLayoutVertex) == 8, "expected HillshadeLayoutVertex size");
 
 } // namespace mbgl
diff --git a/src/mbgl/programs/hillshade_program.cpp b/src/mbgl/programs/hillshade_program.cpp
index 31673afcd4..f054ad4b74 100644
--- a/src/mbgl/programs/hillshade_program.cpp
+++ b/src/mbgl/programs/hillshade_program.cpp
@@ -1,10 +1,7 @@
 #include <mbgl/programs/hillshade_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<HillshadeProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 static_assert(sizeof(HillshadeLayoutVertex) == 8, "expected HillshadeLayoutVertex size");
 
 } // namespace mbgl
diff --git a/src/mbgl/programs/line_program.cpp b/src/mbgl/programs/line_program.cpp
index cab1e7e6fd..40b4617c77 100644
--- a/src/mbgl/programs/line_program.cpp
+++ b/src/mbgl/programs/line_program.cpp
@@ -1,5 +1,4 @@
 #include <mbgl/programs/line_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 #include <mbgl/style/layers/line_layer_properties.hpp>
 #include <mbgl/renderer/render_tile.hpp>
 #include <mbgl/renderer/image_atlas.hpp>
@@ -9,11 +8,6 @@
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<LineProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<LinePatternProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<LineGradientProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<LineSDFProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 using namespace style;
 
 static_assert(sizeof(LineLayoutVertex) == 12, "expected LineLayoutVertex size");
diff --git a/src/mbgl/programs/raster_program.cpp b/src/mbgl/programs/raster_program.cpp
index f3b1052284..6906903e6b 100644
--- a/src/mbgl/programs/raster_program.cpp
+++ b/src/mbgl/programs/raster_program.cpp
@@ -1,10 +1,7 @@
 #include <mbgl/programs/raster_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<RasterProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 static_assert(sizeof(RasterLayoutVertex) == 8, "expected RasterLayoutVertex size");
 
 } // namespace mbgl
diff --git a/src/mbgl/programs/symbol_program.cpp b/src/mbgl/programs/symbol_program.cpp
index 8a7dccd55e..3633bd7c2a 100644
--- a/src/mbgl/programs/symbol_program.cpp
+++ b/src/mbgl/programs/symbol_program.cpp
@@ -1,5 +1,4 @@
 #include <mbgl/programs/symbol_program.hpp>
-#include <mbgl/gfx/context_impl.hpp>
 #include <mbgl/renderer/render_tile.hpp>
 #include <mbgl/map/transform_state.hpp>
 #include <mbgl/style/layers/symbol_layer_impl.hpp>
@@ -10,10 +9,6 @@
 
 namespace mbgl {
 
-template std::unique_ptr<gfx::Program<SymbolIconProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<SymbolSDFTextProgram>> gfx::Context::createProgram(const ProgramParameters&);
-template std::unique_ptr<gfx::Program<SymbolSDFIconProgram>> gfx::Context::createProgram(const ProgramParameters&);
-
 using namespace style;
 
 static_assert(sizeof(SymbolLayoutVertex) == 16, "expected SymbolLayoutVertex size");
diff --git a/test/api/custom_layer.test.cpp b/test/api/custom_layer.test.cpp
index 5afc4152ba..175d053f93 100644
--- a/test/api/custom_layer.test.cpp
+++ b/test/api/custom_layer.test.cpp
@@ -87,6 +87,10 @@ public:
 };
 
 TEST(CustomLayer, Basic) {
+    if (gfx::Backend::GetType() != gfx::Backend::Type::OpenGL) {
+        return;
+    }
+
     util::RunLoop loop;
 
     HeadlessFrontend frontend { 1 };
diff --git a/test/gl/context.test.cpp b/test/gl/context.test.cpp
index 54b0c01d95..4b6bad6f65 100644
--- a/test/gl/context.test.cpp
+++ b/test/gl/context.test.cpp
@@ -85,6 +85,10 @@ struct Buffer {
 };
 
 TEST(GLContextMode, Shared) {
+    if (gfx::Backend::GetType() != gfx::Backend::Type::OpenGL) {
+        return;
+    }
+
     util::RunLoop loop;
 
     HeadlessFrontend frontend { 1, {}, gfx::ContextMode::Shared };
diff --git a/test/map/map.test.cpp b/test/map/map.test.cpp
index 42edaedf22..fd831a05b7 100644
--- a/test/map/map.test.cpp
+++ b/test/map/map.test.cpp
@@ -610,6 +610,10 @@ TEST(Map, AddLayer) {
 }
 
 TEST(Map, WithoutVAOExtension) {
+    if (gfx::Backend::GetType() != gfx::Backend::Type::OpenGL) {
+        return;
+    }
+
     MapTest<DefaultFileSource> test { ":memory:", "test/fixtures/api/assets" };
 
     gfx::BackendScope scope { *test.frontend.getBackend() };
diff --git a/test/src/mbgl/test/test.cpp b/test/src/mbgl/test/test.cpp
index 1c77aae2a1..30df01c488 100644
--- a/test/src/mbgl/test/test.cpp
+++ b/test/src/mbgl/test/test.cpp
@@ -1,9 +1,12 @@
 #include <mbgl/actor/scheduler.hpp>
+#include <mbgl/gfx/backend.hpp>
 #include <mbgl/test.hpp>
 #include <mbgl/test/util.hpp>
 
 #include <gtest/gtest.h>
 
+#include <args.hxx>
+
 namespace mbgl {
 
 int runTests(int argc, char *argv[]) {
@@ -12,6 +15,12 @@ int runTests(int argc, char *argv[]) {
 #endif
 
     testing::InitGoogleTest(&argc, argv);
+
+    args::ArgumentParser argumentParser("Unit tests");
+    args::ValueFlag<std::string> backendValue(argumentParser, "Backend", "Rendering backend", {"backend"});
+
+    argumentParser.ParseCLI(argc, argv);
+
     return RUN_ALL_TESTS();
 }
 
diff --git a/test/util/offscreen_texture.test.cpp b/test/util/offscreen_texture.test.cpp
index ef10984364..ae56b347a4 100644
--- a/test/util/offscreen_texture.test.cpp
+++ b/test/util/offscreen_texture.test.cpp
@@ -14,6 +14,10 @@ using namespace mbgl;
 using namespace mbgl::platform;
 
 TEST(OffscreenTexture, EmptyRed) {
+    if (gfx::Backend::GetType() != gfx::Backend::Type::OpenGL) {
+        return;
+    }
+
     gl::HeadlessBackend backend({ 512, 256 });
     gfx::BackendScope scope { backend };
 
@@ -76,6 +80,10 @@ struct Buffer {
 
 
 TEST(OffscreenTexture, RenderToTexture) {
+    if (gfx::Backend::GetType() != gfx::Backend::Type::OpenGL) {
+        return;
+    }
+
     gl::HeadlessBackend backend({ 512, 256 });
     gfx::BackendScope scope { backend };
     auto& context = static_cast<gl::Context&>(backend.getContext());
-- 
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