7 files changed, 279 insertions, 287 deletions

diff --git a/src/mbgl/gl/context.cpp b/src/mbgl/gl/context.cpp
new file mode 100644
index 0000000000..101e11f4d8
--- /dev/null
+++ b/src/mbgl/gl/context.cpp
@@ -0,0 +1,95 @@
+#include <mbgl/gl/context.hpp>
+
+namespace mbgl {
+namespace gl {
+
+Context::~Context() {
+    reset();
+}
+
+void Context::reset() {
+    std::copy(pooledTextures.begin(), pooledTextures.end(), std::back_inserter(abandonedTextures));
+    pooledTextures.resize(0);
+    performCleanup();
+}
+
+namespace {
+
+template <typename Fn>
+void applyStateFunction(Context& context, Fn&& fn) {
+    fn(context.stencilFunc);
+    fn(context.stencilMask);
+    fn(context.stencilTest);
+    fn(context.stencilOp);
+    fn(context.depthRange);
+    fn(context.depthMask);
+    fn(context.depthTest);
+    fn(context.depthFunc);
+    fn(context.blend);
+    fn(context.blendFunc);
+    fn(context.blendColor);
+    fn(context.colorMask);
+    fn(context.clearDepth);
+    fn(context.clearColor);
+    fn(context.clearStencil);
+    fn(context.program);
+    fn(context.lineWidth);
+    fn(context.activeTexture);
+    fn(context.bindFramebuffer);
+    fn(context.viewport);
+#ifndef GL_ES_VERSION_2_0
+    fn(context.pixelZoom);
+    fn(context.rasterPos);
+#endif // GL_ES_VERSION_2_0
+    for (auto& tex : context.texture) {
+        fn(tex);
+    }
+    fn(context.vertexBuffer);
+    fn(context.elementBuffer);
+    fn(context.vertexArrayObject);
+}
+
+} // namespace
+
+void Context::resetState() {
+    applyStateFunction(*this, [](auto& state) { state.reset(); });
+}
+
+void Context::setDirtyState() {
+    applyStateFunction(*this, [](auto& state) { state.setDirty(); });
+}
+
+void Context::performCleanup() {
+    for (GLuint id : abandonedPrograms) {
+        MBGL_CHECK_ERROR(glDeleteProgram(id));
+    }
+    abandonedPrograms.clear();
+
+    for (GLuint id : abandonedShaders) {
+        MBGL_CHECK_ERROR(glDeleteShader(id));
+    }
+    abandonedShaders.clear();
+
+    if (!abandonedBuffers.empty()) {
+        MBGL_CHECK_ERROR(glDeleteBuffers(int(abandonedBuffers.size()), abandonedBuffers.data()));
+        abandonedBuffers.clear();
+    }
+
+    if (!abandonedTextures.empty()) {
+        MBGL_CHECK_ERROR(glDeleteTextures(int(abandonedTextures.size()), abandonedTextures.data()));
+        abandonedTextures.clear();
+    }
+
+    if (!abandonedVAOs.empty()) {
+        MBGL_CHECK_ERROR(gl::DeleteVertexArrays(int(abandonedVAOs.size()), abandonedVAOs.data()));
+        abandonedVAOs.clear();
+    }
+
+    if (!abandonedFBOs.empty()) {
+        MBGL_CHECK_ERROR(glDeleteFramebuffers(int(abandonedFBOs.size()), abandonedFBOs.data()));
+        abandonedFBOs.clear();
+    }
+}
+
+} // namespace gl
+} // namespace mbgl
diff --git a/src/mbgl/gl/context.hpp b/src/mbgl/gl/context.hpp
index 995f087c6b..5aa55b6a28 100644
--- a/src/mbgl/gl/context.hpp
+++ b/src/mbgl/gl/context.hpp
@@ -1,79 +1,81 @@
 #pragma once
 
+#include <mbgl/gl/object.hpp>
 #include <mbgl/gl/state.hpp>
 #include <mbgl/gl/value.hpp>
+#include <mbgl/util/noncopyable.hpp>
+
+#include <memory>
+#include <vector>
 
 namespace mbgl {
 namespace gl {
 
-class Context {
+constexpr GLsizei TextureMax = 64;
+
+class Context : private util::noncopyable {
 public:
-    void resetState() {
-        stencilFunc.reset();
-        stencilMask.reset();
-        stencilTest.reset();
-        stencilOp.reset();
-        depthRange.reset();
-        depthMask.reset();
-        depthTest.reset();
-        depthFunc.reset();
-        blend.reset();
-        blendFunc.reset();
-        blendColor.reset();
-        colorMask.reset();
-        clearDepth.reset();
-        clearColor.reset();
-        clearStencil.reset();
-        program.reset();
-        lineWidth.reset();
-        activeTexture.reset();
-        bindFramebuffer.reset();
-        viewport.reset();
-#ifndef GL_ES_VERSION_2_0
-        pixelZoom.reset();
-        rasterPos.reset();
-#endif // GL_ES_VERSION_2_0
-        for (auto& tex : texture) {
-            tex.reset();
-        }
-        vertexBuffer.reset();
-        elementBuffer.reset();
-        vertexArrayObject.reset();
+    ~Context();
+
+    UniqueProgram createProgram() {
+        return UniqueProgram { MBGL_CHECK_ERROR(glCreateProgram()), { this } };
     }
 
-    void setDirtyState() {
-        stencilFunc.setDirty();
-        stencilMask.setDirty();
-        stencilTest.setDirty();
-        stencilOp.setDirty();
-        depthRange.setDirty();
-        depthMask.setDirty();
-        depthTest.setDirty();
-        depthFunc.setDirty();
-        blend.setDirty();
-        blendFunc.setDirty();
-        blendColor.setDirty();
-        colorMask.setDirty();
-        clearDepth.setDirty();
-        clearColor.setDirty();
-        clearStencil.setDirty();
-        program.setDirty();
-        lineWidth.setDirty();
-        activeTexture.setDirty();
-        bindFramebuffer.setDirty();
-        viewport.setDirty();
-#ifndef GL_ES_VERSION_2_0
-        pixelZoom.setDirty();
-        rasterPos.setDirty();
-#endif // GL_ES_VERSION_2_0
-        for (auto& tex : texture) {
-            tex.setDirty();
+    UniqueShader createShader(GLenum type) {
+        return UniqueShader { MBGL_CHECK_ERROR(glCreateShader(type)), { this } };
+    }
+
+    UniqueBuffer createBuffer() {
+        GLuint id = 0;
+        MBGL_CHECK_ERROR(glGenBuffers(1, &id));
+        return UniqueBuffer { std::move(id), { this } };
+    }
+
+    UniqueTexture createTexture() {
+        if (pooledTextures.empty()) {
+            pooledTextures.resize(TextureMax);
+            MBGL_CHECK_ERROR(glGenTextures(TextureMax, pooledTextures.data()));
         }
-        vertexBuffer.setDirty();
-        elementBuffer.setDirty();
-        vertexArrayObject.setDirty();
+
+        GLuint id = pooledTextures.back();
+        pooledTextures.pop_back();
+        return UniqueTexture { std::move(id), { this } };
     }
 
+    UniqueVAO createVAO() {
+        GLuint id = 0;
+        MBGL_CHECK_ERROR(gl::GenVertexArrays(1, &id));
+        return UniqueVAO { std::move(id), { this } };
+    }
+
+    UniqueFBO createFBO() {
+        GLuint id = 0;
+        MBGL_CHECK_ERROR(glGenFramebuffers(1, &id));
+        return UniqueFBO { std::move(id), { this } };
+    }
+
+    // Actually remove the objects we marked as abandoned with the above methods.
+    // Only call this while the OpenGL context is exclusive to this thread.
+    void performCleanup();
+
+    // Drain pools and remove abandoned objects, in preparation for destroying the store.
+    // Only call this while the OpenGL context is exclusive to this thread.
+    void reset();
+
+    bool empty() const {
+        return pooledTextures.empty()
+            && abandonedPrograms.empty()
+            && abandonedShaders.empty()
+            && abandonedBuffers.empty()
+            && abandonedTextures.empty()
+            && abandonedVAOs.empty()
+            && abandonedFBOs.empty();
+    }
+
+    void resetState();
+
+    void setDirtyState();
+
     State<value::StencilFunc> stencilFunc;
     State<value::StencilMask> stencilMask;
     State<value::StencilTest> stencilTest;
@@ -102,6 +104,23 @@ public:
     State<value::BindBuffer<GL_ARRAY_BUFFER>> vertexBuffer;
     State<value::BindBuffer<GL_ELEMENT_ARRAY_BUFFER>> elementBuffer;
     State<value::BindVAO> vertexArrayObject;
+
+private:
+    friend detail::ProgramDeleter;
+    friend detail::ShaderDeleter;
+    friend detail::BufferDeleter;
+    friend detail::TextureDeleter;
+    friend detail::VAODeleter;
+    friend detail::FBODeleter;
+
+    std::vector<GLuint> pooledTextures;
+
+    std::vector<GLuint> abandonedPrograms;
+    std::vector<GLuint> abandonedShaders;
+    std::vector<GLuint> abandonedBuffers;
+    std::vector<GLuint> abandonedTextures;
+    std::vector<GLuint> abandonedVAOs;
+    std::vector<GLuint> abandonedFBOs;
 };
 
 } // namespace gl
diff --git a/src/mbgl/gl/object.cpp b/src/mbgl/gl/object.cpp
new file mode 100644
index 0000000000..b9cabb8d9a
--- /dev/null
+++ b/src/mbgl/gl/object.cpp
@@ -0,0 +1,46 @@
+#include <mbgl/gl/object.hpp>
+#include <mbgl/gl/context.hpp>
+
+#include <cassert>
+
+namespace mbgl {
+namespace gl {
+namespace detail {
+
+void ProgramDeleter::operator()(GLuint id) const {
+    assert(context);
+    context->abandonedPrograms.push_back(id);
+}
+
+void ShaderDeleter::operator()(GLuint id) const {
+    assert(context);
+    context->abandonedShaders.push_back(id);
+}
+
+void BufferDeleter::operator()(GLuint id) const {
+    assert(context);
+    context->abandonedBuffers.push_back(id);
+}
+
+void TextureDeleter::operator()(GLuint id) const {
+    assert(context);
+    if (context->pooledTextures.size() >= TextureMax) {
+        context->abandonedTextures.push_back(id);
+    } else {
+        context->pooledTextures.push_back(id);
+    }
+}
+
+void VAODeleter::operator()(GLuint id) const {
+    assert(context);
+    context->abandonedVAOs.push_back(id);
+}
+
+void FBODeleter::operator()(GLuint id) const {
+    assert(context);
+    context->abandonedFBOs.push_back(id);
+}
+
+} // namespace detail
+} // namespace gl
+} // namespace mbgl
diff --git a/src/mbgl/gl/object.hpp b/src/mbgl/gl/object.hpp
new file mode 100644
index 0000000000..44da13042f
--- /dev/null
+++ b/src/mbgl/gl/object.hpp
@@ -0,0 +1,54 @@
+#pragma once
+
+#include <mbgl/gl/gl.hpp>
+
+#include <unique_resource.hpp>
+
+namespace mbgl {
+namespace gl {
+
+class Context;
+
+namespace detail {
+
+struct ProgramDeleter {
+    Context* context;
+    void operator()(GLuint) const;
+};
+
+struct ShaderDeleter {
+    Context* context;
+    void operator()(GLuint) const;
+};
+
+struct BufferDeleter {
+    Context* context;
+    void operator()(GLuint) const;
+};
+
+struct TextureDeleter {
+    Context* context;
+    void operator()(GLuint) const;
+};
+
+struct VAODeleter {
+    Context* context;
+    void operator()(GLuint) const;
+};
+
+struct FBODeleter {
+    Context* context;
+    void operator()(GLuint) const;
+};
+
+} // namespace detail
+
+using UniqueProgram = std_experimental::unique_resource<GLuint, detail::ProgramDeleter>;
+using UniqueShader = std_experimental::unique_resource<GLuint, detail::ShaderDeleter>;
+using UniqueBuffer = std_experimental::unique_resource<GLuint, detail::BufferDeleter>;
+using UniqueTexture = std_experimental::unique_resource<GLuint, detail::TextureDeleter>;
+using UniqueVAO = std_experimental::unique_resource<GLuint, detail::VAODeleter>;
+using UniqueFBO = std_experimental::unique_resource<GLuint, detail::FBODeleter>;
+
+} // namespace gl
+} // namespace mbgl
diff --git a/src/mbgl/gl/object_store.cpp b/src/mbgl/gl/object_store.cpp
deleted file mode 100644
index 9ddbaa7c8c..0000000000
--- a/src/mbgl/gl/object_store.cpp
+++ /dev/null
@@ -1,91 +0,0 @@
-#include <mbgl/gl/object_store.hpp>
-
-#include <cassert>
-
-namespace mbgl {
-namespace gl {
-
-void ProgramDeleter::operator()(GLuint id) const {
-    assert(store);
-    store->abandonedPrograms.push_back(id);
-}
-
-void ShaderDeleter::operator()(GLuint id) const {
-    assert(store);
-    store->abandonedShaders.push_back(id);
-}
-
-void BufferDeleter::operator()(GLuint id) const {
-    assert(store);
-    store->abandonedBuffers.push_back(id);
-}
-
-void TextureDeleter::operator()(GLuint id) const {
-    assert(store);
-    if (store->pooledTextures.size() >= TextureMax) {
-        store->abandonedTextures.push_back(id);
-    } else {
-        store->pooledTextures.push_back(id);
-    }
-}
-
-void VAODeleter::operator()(GLuint id) const {
-    assert(store);
-    store->abandonedVAOs.push_back(id);
-}
-
-void FBODeleter::operator()(GLuint id) const {
-    assert(store);
-    store->abandonedFBOs.push_back(id);
-}
-
-ObjectStore::~ObjectStore() {
-    assert(pooledTextures.empty());
-    assert(abandonedPrograms.empty());
-    assert(abandonedShaders.empty());
-    assert(abandonedBuffers.empty());
-    assert(abandonedTextures.empty());
-    assert(abandonedVAOs.empty());
-    assert(abandonedFBOs.empty());
-}
-
-void ObjectStore::reset() {
-    std::copy(pooledTextures.begin(), pooledTextures.end(), std::back_inserter(abandonedTextures));
-    pooledTextures.resize(0);
-    performCleanup();
-}
-
-void ObjectStore::performCleanup() {
-    for (GLuint id : abandonedPrograms) {
-        MBGL_CHECK_ERROR(glDeleteProgram(id));
-    }
-    abandonedPrograms.clear();
-
-    for (GLuint id : abandonedShaders) {
-        MBGL_CHECK_ERROR(glDeleteShader(id));
-    }
-    abandonedShaders.clear();
-
-    if (!abandonedBuffers.empty()) {
-        MBGL_CHECK_ERROR(glDeleteBuffers(int(abandonedBuffers.size()), abandonedBuffers.data()));
-        abandonedBuffers.clear();
-    }
-
-    if (!abandonedTextures.empty()) {
-        MBGL_CHECK_ERROR(glDeleteTextures(int(abandonedTextures.size()), abandonedTextures.data()));
-        abandonedTextures.clear();
-    }
-
-    if (!abandonedVAOs.empty()) {
-        MBGL_CHECK_ERROR(gl::DeleteVertexArrays(int(abandonedVAOs.size()), abandonedVAOs.data()));
-        abandonedVAOs.clear();
-    }
-
-    if (!abandonedFBOs.empty()) {
-        MBGL_CHECK_ERROR(glDeleteFramebuffers(int(abandonedFBOs.size()), abandonedFBOs.data()));
-        abandonedFBOs.clear();
-    }
-}
-
-} // namespace gl
-} // namespace mbgl
diff --git a/src/mbgl/gl/object_store.hpp b/src/mbgl/gl/object_store.hpp
deleted file mode 100644
index ad9725c556..0000000000
--- a/src/mbgl/gl/object_store.hpp
+++ /dev/null
@@ -1,134 +0,0 @@
-#pragma once
-
-#include <mbgl/gl/gl.hpp>
-#include <mbgl/util/noncopyable.hpp>
-
-#include <unique_resource.hpp>
-
-#include <algorithm>
-#include <memory>
-#include <vector>
-
-namespace mbgl {
-namespace gl {
-
-constexpr GLsizei TextureMax = 64;
-
-class ObjectStore;
-
-struct ProgramDeleter {
-    ObjectStore* store;
-    void operator()(GLuint) const;
-};
-
-struct ShaderDeleter {
-    ObjectStore* store;
-    void operator()(GLuint) const;
-};
-
-struct BufferDeleter {
-    ObjectStore* store;
-    void operator()(GLuint) const;
-};
-
-struct TextureDeleter {
-    ObjectStore* store;
-    void operator()(GLuint) const;
-};
-
-struct VAODeleter {
-    ObjectStore* store;
-    void operator()(GLuint) const;
-};
-
-struct FBODeleter {
-    ObjectStore* store;
-    void operator()(GLuint) const;
-};
-
-using UniqueProgram = std_experimental::unique_resource<GLuint, ProgramDeleter>;
-using UniqueShader = std_experimental::unique_resource<GLuint, ShaderDeleter>;
-using UniqueBuffer = std_experimental::unique_resource<GLuint, BufferDeleter>;
-using UniqueTexture = std_experimental::unique_resource<GLuint, TextureDeleter>;
-using UniqueVAO = std_experimental::unique_resource<GLuint, VAODeleter>;
-using UniqueFBO = std_experimental::unique_resource<GLuint, FBODeleter>;
-
-class ObjectStore : private util::noncopyable {
-public:
-    ~ObjectStore();
-
-    UniqueProgram createProgram() {
-        return UniqueProgram { MBGL_CHECK_ERROR(glCreateProgram()), { this } };
-    }
-
-    UniqueShader createShader(GLenum type) {
-        return UniqueShader { MBGL_CHECK_ERROR(glCreateShader(type)), { this } };
-    }
-
-    UniqueBuffer createBuffer() {
-        GLuint id = 0;
-        MBGL_CHECK_ERROR(glGenBuffers(1, &id));
-        return UniqueBuffer { std::move(id), { this } };
-    }
-
-    UniqueTexture createTexture() {
-        if (pooledTextures.empty()) {
-            pooledTextures.resize(TextureMax);
-            MBGL_CHECK_ERROR(glGenTextures(TextureMax, pooledTextures.data()));
-        }
-
-        GLuint id = pooledTextures.back();
-        pooledTextures.pop_back();
-        return UniqueTexture { std::move(id), { this } };
-    }
-
-    UniqueVAO createVAO() {
-        GLuint id = 0;
-        MBGL_CHECK_ERROR(gl::GenVertexArrays(1, &id));
-        return UniqueVAO { std::move(id), { this } };
-    }
-
-    UniqueFBO createFBO() {
-        GLuint id = 0;
-        MBGL_CHECK_ERROR(glGenFramebuffers(1, &id));
-        return UniqueFBO { std::move(id), { this } };
-    }
-
-    // Actually remove the objects we marked as abandoned with the above methods.
-    // Only call this while the OpenGL context is exclusive to this thread.
-    void performCleanup();
-
-    // Drain pools and remove abandoned objects, in preparation for destroying the store.
-    // Only call this while the OpenGL context is exclusive to this thread.
-    void reset();
-
-    bool empty() const {
-        return pooledTextures.empty()
-            && abandonedPrograms.empty()
-            && abandonedShaders.empty()
-            && abandonedBuffers.empty()
-            && abandonedTextures.empty()
-            && abandonedVAOs.empty()
-            && abandonedFBOs.empty();
-    }
-
-private:
-    friend ProgramDeleter;
-    friend ShaderDeleter;
-    friend BufferDeleter;
-    friend TextureDeleter;
-    friend VAODeleter;
-    friend FBODeleter;
-
-    std::vector<GLuint> pooledTextures;
-
-    std::vector<GLuint> abandonedPrograms;
-    std::vector<GLuint> abandonedShaders;
-    std::vector<GLuint> abandonedBuffers;
-    std::vector<GLuint> abandonedTextures;
-    std::vector<GLuint> abandonedVAOs;
-    std::vector<GLuint> abandonedFBOs;
-};
-
-} // namespace gl
-} // namespace mbgl
diff --git a/src/mbgl/gl/state.hpp b/src/mbgl/gl/state.hpp
index 274ae5e2fe..c7a7d74c63 100644
--- a/src/mbgl/gl/state.hpp
+++ b/src/mbgl/gl/state.hpp
@@ -45,10 +45,13 @@ public:
         return dirty || currentValue != value;
     }
 
+    // Explicitly resets the piece of OpenGL state to its default value.
     void reset() {
         *this = defaultValue;
     }
 
+    // Mark the state as dirty. This means that the next time we are assigning a value to this
+    // piece of OpenGL state will always result in an actual OpenGL call.
     void setDirty() {
         dirty = true;
     }