[core] refactor program object creation

3 files changed, 17 insertions, 10 deletions

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