From 865f8a6c03540e329ed6caef354799fb58b7ab6e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Konstantin=20K=C3=A4fer?= <mail@kkaefer.com>
Date: Mon, 1 Apr 2019 13:48:20 +0200
Subject: [core] add gfx::Renderable and gfx::OffscreenTexture

---
 include/mbgl/gfx/renderable.hpp                    |  44 +++++++++
 include/mbgl/gl/renderable_resource.hpp            |  17 ++++
 src/core-files.json                                |   7 +-
 src/mbgl/gfx/context.hpp                           |  10 +++
 src/mbgl/gfx/offscreen_texture.hpp                 |  25 ++++++
 src/mbgl/gl/context.cpp                            |  12 +++
 src/mbgl/gl/context.hpp                            |   7 ++
 src/mbgl/gl/offscreen_texture.cpp                  |  87 ++++++++++++++++++
 src/mbgl/gl/offscreen_texture.hpp                  |  26 ++++++
 .../layers/render_fill_extrusion_layer.cpp         |   6 +-
 .../layers/render_fill_extrusion_layer.hpp         |   5 +-
 src/mbgl/renderer/layers/render_heatmap_layer.cpp  |  19 ++--
 src/mbgl/renderer/layers/render_heatmap_layer.hpp  |   4 +-
 .../renderer/layers/render_hillshade_layer.cpp     |   9 +-
 src/mbgl/util/offscreen_texture.cpp                | 100 ---------------------
 src/mbgl/util/offscreen_texture.hpp                |  39 --------
 test/util/offscreen_texture.test.cpp               |   7 +-
 17 files changed, 260 insertions(+), 164 deletions(-)
 create mode 100644 include/mbgl/gfx/renderable.hpp
 create mode 100644 include/mbgl/gl/renderable_resource.hpp
 create mode 100644 src/mbgl/gfx/offscreen_texture.hpp
 create mode 100644 src/mbgl/gl/offscreen_texture.cpp
 create mode 100644 src/mbgl/gl/offscreen_texture.hpp
 delete mode 100644 src/mbgl/util/offscreen_texture.cpp
 delete mode 100644 src/mbgl/util/offscreen_texture.hpp

diff --git a/include/mbgl/gfx/renderable.hpp b/include/mbgl/gfx/renderable.hpp
new file mode 100644
index 0000000000..3a973e6693
--- /dev/null
+++ b/include/mbgl/gfx/renderable.hpp
@@ -0,0 +1,44 @@
+#pragma once
+
+#include <mbgl/util/size.hpp>
+
+#include <memory>
+#include <cassert>
+
+namespace mbgl {
+namespace gfx {
+
+class RenderableResource {
+protected:
+    explicit RenderableResource() = default;
+
+public:
+    virtual ~RenderableResource() = default;
+    RenderableResource(const RenderableResource&) = delete;
+    RenderableResource& operator=(const RenderableResource&) = delete;
+};
+
+class Renderable {
+protected:
+    Renderable(const Size size_, std::unique_ptr<RenderableResource> resource_)
+        : size(size_), resource(std::move(resource_)) {
+    }
+
+public:
+    Size getSize() const {
+        return size;
+    }
+
+    template <typename T>
+    T& getResource() const {
+        assert(resource);
+        return static_cast<T&>(*resource);
+    }
+
+protected:
+    Size size;
+    std::unique_ptr<RenderableResource> resource;
+};
+
+} // namespace gfx
+} // namespace mbgl
diff --git a/include/mbgl/gl/renderable_resource.hpp b/include/mbgl/gl/renderable_resource.hpp
new file mode 100644
index 0000000000..0be0ae9c67
--- /dev/null
+++ b/include/mbgl/gl/renderable_resource.hpp
@@ -0,0 +1,17 @@
+#pragma once
+
+#include <mbgl/gfx/renderable.hpp>
+
+namespace mbgl {
+namespace gl {
+
+class RenderableResource : public gfx::RenderableResource {
+protected:
+    explicit RenderableResource() = default;
+
+public:
+    virtual void bind() = 0;
+};
+
+} // namespace gl
+} // namespace mbgl
diff --git a/src/core-files.json b/src/core-files.json
index f95d43e743..98d1de3765 100644
--- a/src/core-files.json
+++ b/src/core-files.json
@@ -24,6 +24,7 @@
         "src/mbgl/gl/debugging_extension.cpp",
         "src/mbgl/gl/enum.cpp",
         "src/mbgl/gl/object.cpp",
+        "src/mbgl/gl/offscreen_texture.cpp",
         "src/mbgl/gl/texture.cpp",
         "src/mbgl/gl/uniform.cpp",
         "src/mbgl/gl/value.cpp",
@@ -299,7 +300,6 @@
         "src/mbgl/util/mat2.cpp",
         "src/mbgl/util/mat3.cpp",
         "src/mbgl/util/mat4.cpp",
-        "src/mbgl/util/offscreen_texture.cpp",
         "src/mbgl/util/premultiply.cpp",
         "src/mbgl/util/rapidjson.cpp",
         "src/mbgl/util/stopwatch.cpp",
@@ -321,6 +321,8 @@
         "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/renderable.hpp": "include/mbgl/gfx/renderable.hpp",
+        "mbgl/gl/renderable_resource.hpp": "include/mbgl/gl/renderable_resource.hpp",
         "mbgl/layermanager/background_layer_factory.hpp": "include/mbgl/layermanager/background_layer_factory.hpp",
         "mbgl/layermanager/circle_layer_factory.hpp": "include/mbgl/layermanager/circle_layer_factory.hpp",
         "mbgl/layermanager/custom_layer_factory.hpp": "include/mbgl/layermanager/custom_layer_factory.hpp",
@@ -520,6 +522,7 @@
         "mbgl/gfx/draw_scope.hpp": "src/mbgl/gfx/draw_scope.hpp",
         "mbgl/gfx/index_buffer.hpp": "src/mbgl/gfx/index_buffer.hpp",
         "mbgl/gfx/index_vector.hpp": "src/mbgl/gfx/index_vector.hpp",
+        "mbgl/gfx/offscreen_texture.hpp": "src/mbgl/gfx/offscreen_texture.hpp",
         "mbgl/gfx/program.hpp": "src/mbgl/gfx/program.hpp",
         "mbgl/gfx/renderbuffer.hpp": "src/mbgl/gfx/renderbuffer.hpp",
         "mbgl/gfx/stencil_mode.hpp": "src/mbgl/gfx/stencil_mode.hpp",
@@ -541,6 +544,7 @@
         "mbgl/gl/framebuffer.hpp": "src/mbgl/gl/framebuffer.hpp",
         "mbgl/gl/index_buffer_resource.hpp": "src/mbgl/gl/index_buffer_resource.hpp",
         "mbgl/gl/object.hpp": "src/mbgl/gl/object.hpp",
+        "mbgl/gl/offscreen_texture.hpp": "src/mbgl/gl/offscreen_texture.hpp",
         "mbgl/gl/program.hpp": "src/mbgl/gl/program.hpp",
         "mbgl/gl/program_binary_extension.hpp": "src/mbgl/gl/program_binary_extension.hpp",
         "mbgl/gl/renderbuffer_resource.hpp": "src/mbgl/gl/renderbuffer_resource.hpp",
@@ -757,7 +761,6 @@
         "mbgl/util/mat3.hpp": "src/mbgl/util/mat3.hpp",
         "mbgl/util/mat4.hpp": "src/mbgl/util/mat4.hpp",
         "mbgl/util/math.hpp": "src/mbgl/util/math.hpp",
-        "mbgl/util/offscreen_texture.hpp": "src/mbgl/util/offscreen_texture.hpp",
         "mbgl/util/rapidjson.hpp": "src/mbgl/util/rapidjson.hpp",
         "mbgl/util/rect.hpp": "src/mbgl/util/rect.hpp",
         "mbgl/util/std.hpp": "src/mbgl/util/std.hpp",
diff --git a/src/mbgl/gfx/context.hpp b/src/mbgl/gfx/context.hpp
index 1ce00f04d1..c956debcb0 100644
--- a/src/mbgl/gfx/context.hpp
+++ b/src/mbgl/gfx/context.hpp
@@ -17,6 +17,8 @@ class ProgramParameters;
 
 namespace gfx {
 
+class OffscreenTexture;
+
 class Context {
 protected:
     Context(ContextType type_, uint32_t maximumVertexBindingCount_)
@@ -123,6 +125,14 @@ protected:
     virtual void updateTextureResourceSub(TextureResource&, uint16_t xOffset, uint16_t yOffset, Size, const void* data,
         TexturePixelType, TextureChannelDataType) = 0;
 
+public:
+    virtual std::unique_ptr<gfx::OffscreenTexture> createOffscreenTexture(
+        Size, gfx::TextureChannelDataType = gfx::TextureChannelDataType::UnsignedByte) = 0;
+    virtual std::unique_ptr<gfx::OffscreenTexture> createOffscreenTexture(
+        Size,
+        gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>&,
+        gfx::TextureChannelDataType = gfx::TextureChannelDataType::UnsignedByte) = 0;
+
 public:
     template <RenderbufferPixelType pixelType>
     Renderbuffer<pixelType>
diff --git a/src/mbgl/gfx/offscreen_texture.hpp b/src/mbgl/gfx/offscreen_texture.hpp
new file mode 100644
index 0000000000..1eaf4557c6
--- /dev/null
+++ b/src/mbgl/gfx/offscreen_texture.hpp
@@ -0,0 +1,25 @@
+#pragma once
+
+#include <mbgl/gfx/renderable.hpp>
+#include <mbgl/util/image.hpp>
+
+namespace mbgl {
+namespace gfx {
+
+class Texture;
+
+class OffscreenTexture : public gfx::Renderable {
+protected:
+    OffscreenTexture(const Size size_, std::unique_ptr<RenderableResource> resource_)
+        : gfx::Renderable(size_, std::move(resource_)) {
+    }
+
+public:
+    virtual ~OffscreenTexture() = default;
+
+    virtual PremultipliedImage readStillImage() = 0;
+    virtual gfx::Texture& getTexture() = 0;
+};
+
+} // namespace gfx
+} // namespace mbgl
diff --git a/src/mbgl/gl/context.cpp b/src/mbgl/gl/context.cpp
index f4e565c766..d33ae067f6 100644
--- a/src/mbgl/gl/context.cpp
+++ b/src/mbgl/gl/context.cpp
@@ -6,6 +6,7 @@
 #include <mbgl/gl/renderbuffer_resource.hpp>
 #include <mbgl/gl/draw_scope_resource.hpp>
 #include <mbgl/gl/texture.hpp>
+#include <mbgl/gl/offscreen_texture.hpp>
 #include <mbgl/gl/command_encoder.hpp>
 #include <mbgl/gl/debugging_extension.hpp>
 #include <mbgl/gl/vertex_array_extension.hpp>
@@ -553,6 +554,17 @@ void Context::updateTextureResourceSub(gfx::TextureResource& resource,
                                   Enum<gfx::TextureChannelDataType>::to(type), data));
 }
 
+std::unique_ptr<gfx::OffscreenTexture>
+Context::createOffscreenTexture(const Size size, const gfx::TextureChannelDataType type) {
+    return std::make_unique<gl::OffscreenTexture>(*this, size, type);
+}
+
+std::unique_ptr<gfx::OffscreenTexture>
+Context::createOffscreenTexture(const Size size,
+                                gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>& depth,
+                                gfx::TextureChannelDataType type) {
+    return std::make_unique<gl::OffscreenTexture>(*this, size, depth, type);
+}
 
 std::unique_ptr<gfx::DrawScopeResource> Context::createDrawScopeResource() {
     return std::make_unique<gl::DrawScopeResource>(createVertexArray());
diff --git a/src/mbgl/gl/context.hpp b/src/mbgl/gl/context.hpp
index 530ff1c73f..2fb1d242ce 100644
--- a/src/mbgl/gl/context.hpp
+++ b/src/mbgl/gl/context.hpp
@@ -201,6 +201,13 @@ private:
     void updateTextureResource(gfx::TextureResource&, Size, const void* data, gfx::TexturePixelType, gfx::TextureChannelDataType) override;
     void updateTextureResourceSub(gfx::TextureResource&, const uint16_t xOffset, const uint16_t yOffset, Size, const void* data, gfx::TexturePixelType, gfx::TextureChannelDataType) override;
 
+    std::unique_ptr<gfx::OffscreenTexture> createOffscreenTexture(
+        Size, gfx::TextureChannelDataType = gfx::TextureChannelDataType::UnsignedByte) override;
+    std::unique_ptr<gfx::OffscreenTexture> createOffscreenTexture(
+        Size,
+        gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>&,
+        gfx::TextureChannelDataType = gfx::TextureChannelDataType::UnsignedByte) override;
+
     std::unique_ptr<gfx::RenderbufferResource> createRenderbufferResource(gfx::RenderbufferPixelType, Size size) override;
 
     std::unique_ptr<gfx::DrawScopeResource> createDrawScopeResource() override;
diff --git a/src/mbgl/gl/offscreen_texture.cpp b/src/mbgl/gl/offscreen_texture.cpp
new file mode 100644
index 0000000000..96d8b7e4c4
--- /dev/null
+++ b/src/mbgl/gl/offscreen_texture.cpp
@@ -0,0 +1,87 @@
+#include <mbgl/gl/offscreen_texture.hpp>
+#include <mbgl/gl/renderable_resource.hpp>
+#include <mbgl/gl/context.hpp>
+#include <mbgl/gl/framebuffer.hpp>
+
+namespace mbgl {
+namespace gl {
+
+class OffscreenTextureResource final : public gl::RenderableResource {
+public:
+    OffscreenTextureResource(gl::Context& context_,
+                             const Size size_,
+                             const gfx::TextureChannelDataType type_)
+        : context(context_), size(size_), type(type_) {
+        assert(!size.isEmpty());
+    }
+
+    OffscreenTextureResource(gl::Context& context_,
+                             const Size size_,
+                             gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>& depth_,
+                             const gfx::TextureChannelDataType type_)
+        : context(context_), size(size_), depth(&depth_), type(type_) {
+        assert(!size.isEmpty());
+    }
+
+    void bind() override {
+        if (!framebuffer) {
+            texture = context.createTexture(size, gfx::TexturePixelType::RGBA, type);
+            if (depth) {
+                framebuffer = context.createFramebuffer(*texture, *depth);
+            } else {
+                framebuffer = context.createFramebuffer(*texture);
+            }
+        } else {
+            context.bindFramebuffer = framebuffer->framebuffer;
+        }
+
+        context.activeTextureUnit = 0;
+        context.scissorTest = false;
+        context.viewport = { 0, 0, size };
+    }
+
+    PremultipliedImage readStillImage() {
+        assert(framebuffer);
+        context.bindFramebuffer = framebuffer->framebuffer;
+        return context.readFramebuffer<PremultipliedImage>(size);
+    }
+
+    gfx::Texture& getTexture() {
+        assert(texture);
+        return *texture;
+    }
+
+private:
+    gl::Context& context;
+    const Size size;
+    optional<gfx::Texture> texture;
+    gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>* depth = nullptr;
+    const gfx::TextureChannelDataType type;
+    optional<gl::Framebuffer> framebuffer;
+};
+
+OffscreenTexture::OffscreenTexture(gl::Context& context,
+                                   const Size size_,
+                                   const gfx::TextureChannelDataType type)
+    : gfx::OffscreenTexture(size, std::make_unique<OffscreenTextureResource>(context, size_, type)) {
+}
+
+OffscreenTexture::OffscreenTexture(
+    gl::Context& context,
+    const Size size_,
+    gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>& renderbuffer,
+    const gfx::TextureChannelDataType type)
+    : gfx::OffscreenTexture(
+          size, std::make_unique<OffscreenTextureResource>(context, size_, renderbuffer, type)) {
+}
+
+PremultipliedImage OffscreenTexture::readStillImage() {
+    return getResource<OffscreenTextureResource>().readStillImage();
+}
+
+gfx::Texture& OffscreenTexture::getTexture() {
+    return getResource<OffscreenTextureResource>().getTexture();
+}
+
+} // namespace gl
+} // namespace mbgl
diff --git a/src/mbgl/gl/offscreen_texture.hpp b/src/mbgl/gl/offscreen_texture.hpp
new file mode 100644
index 0000000000..5b211df505
--- /dev/null
+++ b/src/mbgl/gl/offscreen_texture.hpp
@@ -0,0 +1,26 @@
+#pragma once
+
+#include <mbgl/gfx/offscreen_texture.hpp>
+#include <mbgl/gfx/renderbuffer.hpp>
+
+namespace mbgl {
+namespace gl {
+
+class Context;
+
+class OffscreenTexture final : public gfx::OffscreenTexture {
+public:
+    OffscreenTexture(gl::Context&,
+                     Size size,
+                     gfx::TextureChannelDataType type = gfx::TextureChannelDataType::UnsignedByte);
+    OffscreenTexture(gl::Context&,
+                     Size size,
+                     gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>&,
+                     gfx::TextureChannelDataType type = gfx::TextureChannelDataType::UnsignedByte);
+
+    PremultipliedImage readStillImage() override;
+    gfx::Texture& getTexture() override;
+};
+
+} // namespace gl
+} // namespace mbgl
diff --git a/src/mbgl/renderer/layers/render_fill_extrusion_layer.cpp b/src/mbgl/renderer/layers/render_fill_extrusion_layer.cpp
index 39eb6f151d..d7c59570c1 100644
--- a/src/mbgl/renderer/layers/render_fill_extrusion_layer.cpp
+++ b/src/mbgl/renderer/layers/render_fill_extrusion_layer.cpp
@@ -15,6 +15,7 @@
 #include <mbgl/tile/geometry_tile.hpp>
 #include <mbgl/gfx/cull_face_mode.hpp>
 #include <mbgl/gl/context.hpp>
+#include <mbgl/gl/renderable_resource.hpp>
 
 namespace mbgl {
 
@@ -62,10 +63,11 @@ void RenderFillExtrusionLayer::render(PaintParameters& parameters, RenderSource*
         const auto& size = parameters.staticData.backendSize;
 
         if (!renderTexture || renderTexture->getSize() != size) {
-            renderTexture = OffscreenTexture(parameters.context, size, *parameters.staticData.depthRenderbuffer);
+            renderTexture.reset();
+            renderTexture = parameters.context.createOffscreenTexture(size, *parameters.staticData.depthRenderbuffer);
         }
 
-        renderTexture->bind();
+        renderTexture->getResource<gl::RenderableResource>().bind();
 
         optional<float> depthClearValue = {};
         if (parameters.staticData.depthRenderbuffer->needsClearing()) depthClearValue = 1.0;
diff --git a/src/mbgl/renderer/layers/render_fill_extrusion_layer.hpp b/src/mbgl/renderer/layers/render_fill_extrusion_layer.hpp
index 886362f28e..6f14fcd7a8 100644
--- a/src/mbgl/renderer/layers/render_fill_extrusion_layer.hpp
+++ b/src/mbgl/renderer/layers/render_fill_extrusion_layer.hpp
@@ -3,8 +3,7 @@
 #include <mbgl/renderer/render_layer.hpp>
 #include <mbgl/style/layers/fill_extrusion_layer_impl.hpp>
 #include <mbgl/style/layers/fill_extrusion_layer_properties.hpp>
-#include <mbgl/util/optional.hpp>
-#include <mbgl/util/offscreen_texture.hpp>
+#include <mbgl/gfx/offscreen_texture.hpp>
 
 namespace mbgl {
 
@@ -41,7 +40,7 @@ public:
 
     const style::FillExtrusionLayer::Impl& impl() const;
 
-    optional<OffscreenTexture> renderTexture;
+    std::unique_ptr<gfx::OffscreenTexture> renderTexture;
 private:
     CrossfadeParameters crossfade;
 };
diff --git a/src/mbgl/renderer/layers/render_heatmap_layer.cpp b/src/mbgl/renderer/layers/render_heatmap_layer.cpp
index c720709e28..15345ffe9e 100644
--- a/src/mbgl/renderer/layers/render_heatmap_layer.cpp
+++ b/src/mbgl/renderer/layers/render_heatmap_layer.cpp
@@ -11,6 +11,7 @@
 #include <mbgl/geometry/feature_index.hpp>
 #include <mbgl/gfx/cull_face_mode.hpp>
 #include <mbgl/gl/context.hpp>
+#include <mbgl/gl/renderable_resource.hpp>
 #include <mbgl/util/math.hpp>
 #include <mbgl/util/intersection_tests.hpp>
 
@@ -57,27 +58,27 @@ void RenderHeatmapLayer::render(PaintParameters& parameters, RenderSource*) {
         const auto size = Size{viewportSize.width / 4, viewportSize.height / 4};
 
         if (!renderTexture || renderTexture->getSize() != size) {
+            renderTexture.reset();
             if (parameters.context.supportsHalfFloatTextures) {
-                renderTexture = OffscreenTexture(parameters.context, size, gfx::TextureChannelDataType::HalfFloat);
+                renderTexture = parameters.context.createOffscreenTexture(size, gfx::TextureChannelDataType::HalfFloat);
 
+                // TODO: try binding in the offscreen texture constructor
                 try {
-                    renderTexture->bind();
+                    renderTexture->getResource<gl::RenderableResource>().bind();
                 } catch (const std::runtime_error& ex) {
                     // can't render to a half-float texture; falling back to unsigned byte one
-                    renderTexture = nullopt;
+                    renderTexture.reset();
                     parameters.context.supportsHalfFloatTextures = false;
                 }
             }
 
-            if (!parameters.context.supportsHalfFloatTextures || !renderTexture) {
-                renderTexture = OffscreenTexture(parameters.context, size, gfx::TextureChannelDataType::UnsignedByte);
-                renderTexture->bind();
+            if (!renderTexture) {
+                renderTexture = parameters.context.createOffscreenTexture(size, gfx::TextureChannelDataType::UnsignedByte);
             }
-
-        } else {
-            renderTexture->bind();
         }
 
+        renderTexture->getResource<gl::RenderableResource>().bind();
+
         if (!colorRampTexture) {
             colorRampTexture = parameters.context.createTexture(colorRamp, gfx::TextureChannelDataType::UnsignedByte);
         }
diff --git a/src/mbgl/renderer/layers/render_heatmap_layer.hpp b/src/mbgl/renderer/layers/render_heatmap_layer.hpp
index 364628a2b2..22fe48f374 100644
--- a/src/mbgl/renderer/layers/render_heatmap_layer.hpp
+++ b/src/mbgl/renderer/layers/render_heatmap_layer.hpp
@@ -4,8 +4,8 @@
 #include <mbgl/style/layers/heatmap_layer_impl.hpp>
 #include <mbgl/style/layers/heatmap_layer_properties.hpp>
 #include <mbgl/gfx/texture.hpp>
+#include <mbgl/gfx/offscreen_texture.hpp>
 #include <mbgl/util/optional.hpp>
-#include <mbgl/util/offscreen_texture.hpp>
 
 namespace mbgl {
 
@@ -36,7 +36,7 @@ public:
     const style::HeatmapLayer::Impl& impl() const;
 
     PremultipliedImage colorRamp;
-    optional<OffscreenTexture> renderTexture;
+    std::unique_ptr<gfx::OffscreenTexture> renderTexture;
     optional<gfx::Texture> colorRampTexture;
 
 private:
diff --git a/src/mbgl/renderer/layers/render_hillshade_layer.cpp b/src/mbgl/renderer/layers/render_hillshade_layer.cpp
index 527d48f654..426c34e599 100644
--- a/src/mbgl/renderer/layers/render_hillshade_layer.cpp
+++ b/src/mbgl/renderer/layers/render_hillshade_layer.cpp
@@ -10,8 +10,9 @@
 #include <mbgl/tile/tile.hpp>
 #include <mbgl/style/layers/hillshade_layer_impl.hpp>
 #include <mbgl/gfx/cull_face_mode.hpp>
+#include <mbgl/gfx/offscreen_texture.hpp>
+#include <mbgl/gl/renderable_resource.hpp>
 #include <mbgl/util/geo.hpp>
-#include <mbgl/util/offscreen_texture.hpp>
 
 namespace mbgl {
 
@@ -130,8 +131,8 @@ void RenderHillshadeLayer::render(PaintParameters& parameters, RenderSource* src
             assert(bucket.dem);
             const uint16_t stride = bucket.getDEMData().stride;
             const uint16_t tilesize = bucket.getDEMData().dim;
-            OffscreenTexture view(parameters.context, { tilesize, tilesize });
-            view.bind();
+            auto view = parameters.context.createOffscreenTexture({ tilesize, tilesize });
+            view->getResource<gl::RenderableResource>().bind();
 
             const Properties<>::PossiblyEvaluated properties;
             const HillshadePrepareProgram::Binders paintAttributeData{ properties, 0 };
@@ -173,7 +174,7 @@ void RenderHillshadeLayer::render(PaintParameters& parameters, RenderSource* src
                 },
                 getID()
             );
-            bucket.texture = std::move(view.getTexture());
+            bucket.texture = std::move(view->getTexture());
             bucket.setPrepared(true);
         } else if (parameters.pass == RenderPass::Translucent) {
             assert(bucket.texture);
diff --git a/src/mbgl/util/offscreen_texture.cpp b/src/mbgl/util/offscreen_texture.cpp
deleted file mode 100644
index 9fa1dcd90e..0000000000
--- a/src/mbgl/util/offscreen_texture.cpp
+++ /dev/null
@@ -1,100 +0,0 @@
-#include <mbgl/gl/context.hpp>
-#include <mbgl/util/offscreen_texture.hpp>
-
-#include <cassert>
-#include <cstring>
-
-namespace mbgl {
-
-OffscreenTexture::OffscreenTexture(OffscreenTexture&&) = default;
-OffscreenTexture& OffscreenTexture::operator=(OffscreenTexture&&) = default;
-
-class OffscreenTexture::Impl {
-public:
-    Impl(gl::Context& context_, const Size size_, const gfx::TextureChannelDataType type_)
-        : context(context_), size(std::move(size_)), type(type_) {
-        assert(!size.isEmpty());
-    }
-    Impl(gl::Context& context_,
-         const Size size_,
-         gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>& depth_,
-         const gfx::TextureChannelDataType type_)
-        : context(context_), size(std::move(size_)), depth(&depth_), type(type_) {
-        assert(!size.isEmpty());
-    }
-
-    void bind() {
-        if (!framebuffer) {
-            texture = context.createTexture(size, gfx::TexturePixelType::RGBA, type);
-            if (depth) {
-                framebuffer = context.createFramebuffer(*texture, *depth);
-            } else {
-                framebuffer = context.createFramebuffer(*texture);
-            }
-        } else {
-            context.bindFramebuffer = framebuffer->framebuffer;
-        }
-
-        context.activeTextureUnit = 0;
-        context.scissorTest = false;
-        context.viewport = { 0, 0, size };
-    }
-
-    PremultipliedImage readStillImage() {
-        return context.readFramebuffer<PremultipliedImage>(size);
-    }
-
-    gfx::Texture& getTexture() {
-        assert(texture);
-        return *texture;
-    }
-
-    const Size& getSize() const {
-        return size;
-    }
-
-private:
-    gl::Context& context;
-    const Size size;
-    optional<gl::Framebuffer> framebuffer;
-    optional<gfx::Texture> texture;
-    gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>* depth = nullptr;
-    const gfx::TextureChannelDataType type;
-};
-
-OffscreenTexture::OffscreenTexture(gfx::Context& context,
-                                   const Size size,
-                                   const gfx::TextureChannelDataType type)
-    // TODO: remove cast
-    : impl(std::make_unique<Impl>(static_cast<gl::Context&>(context), std::move(size), type)) {
-    assert(!size.isEmpty());
-}
-
-OffscreenTexture::OffscreenTexture(gfx::Context& context,
-                                   const Size size,
-                                   gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>& renderbuffer,
-                                   const gfx::TextureChannelDataType type)
-    // TODO: remove cast
-    : impl(std::make_unique<Impl>(static_cast<gl::Context&>(context), std::move(size), renderbuffer, type)) {
-    assert(!size.isEmpty());
-}
-
-OffscreenTexture::~OffscreenTexture() = default;
-
-void OffscreenTexture::bind() {
-    impl->bind();
-}
-
-PremultipliedImage OffscreenTexture::readStillImage() {
-    return impl->readStillImage();
-}
-
-gfx::Texture& OffscreenTexture::getTexture() {
-    return impl->getTexture();
-}
-
-const Size& OffscreenTexture::getSize() const {
-    return impl->getSize();
-}
-
-} // namespace mbgl
diff --git a/src/mbgl/util/offscreen_texture.hpp b/src/mbgl/util/offscreen_texture.hpp
deleted file mode 100644
index db8cfac559..0000000000
--- a/src/mbgl/util/offscreen_texture.hpp
+++ /dev/null
@@ -1,39 +0,0 @@
-#pragma once
-
-#include <mbgl/gfx/renderbuffer.hpp>
-#include <mbgl/util/image.hpp>
-
-namespace mbgl {
-
-namespace gfx {
-class Context;
-class Texture;
-} // namespace gfx
-
-class OffscreenTexture {
-public:
-    OffscreenTexture(gfx::Context&,
-                     Size size = { 256, 256 },
-                     gfx::TextureChannelDataType type = gfx::TextureChannelDataType::UnsignedByte);
-    OffscreenTexture(gfx::Context&,
-                     Size size,
-                     gfx::Renderbuffer<gfx::RenderbufferPixelType::Depth>&,
-                     gfx::TextureChannelDataType type = gfx::TextureChannelDataType::UnsignedByte);
-    ~OffscreenTexture();
-    OffscreenTexture(OffscreenTexture&&);
-    OffscreenTexture& operator=(OffscreenTexture&&);
-
-    void bind();
-
-    PremultipliedImage readStillImage();
-
-    gfx::Texture& getTexture();
-
-    const Size& getSize() const;
-
-private:
-    class Impl;
-    std::unique_ptr<Impl> impl;
-};
-
-} // namespace mbgl
diff --git a/test/util/offscreen_texture.test.cpp b/test/util/offscreen_texture.test.cpp
index 0f24c1e9af..887a1cdc00 100644
--- a/test/util/offscreen_texture.test.cpp
+++ b/test/util/offscreen_texture.test.cpp
@@ -4,10 +4,11 @@
 #include <mbgl/gl/context.hpp>
 #include <mbgl/gl/texture.hpp>
 #include <mbgl/gl/defines.hpp>
+#include <mbgl/gl/renderable_resource.hpp>
 #include <mbgl/gl/headless_backend.hpp>
 #include <mbgl/renderer/backend_scope.hpp>
+#include <mbgl/gl/offscreen_texture.hpp>
 
-#include <mbgl/util/offscreen_texture.hpp>
 
 using namespace mbgl;
 using namespace mbgl::platform;
@@ -132,13 +133,13 @@ void main() {
 
     // Then, create a texture, bind it, and render yellow to that texture. This should not
     // affect the originally bound FBO.
-    OffscreenTexture texture(context, { 128, 128 });
+    gl::OffscreenTexture texture(context, { 128, 128 });
 
     // Scissor test shouldn't leak after OffscreenTexture::bind().
     MBGL_CHECK_ERROR(glScissor(32, 32, 64, 64));
     context.scissorTest.setCurrentValue(true);
 
-    texture.bind();
+    texture.getResource<gl::RenderableResource>().bind();
 
     context.clear(Color(), {}, {});
 
-- 
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