[core] move GL value objects from gl_config.hpp to gl_values.hpp

Also removes duplicate code from gl_helper.hpp by reusing the GL values that we already have anyway.

7 files changed, 148 insertions, 166 deletions

diff --git a/include/mbgl/gl/gl_helper.hpp b/include/mbgl/gl/gl_helper.hpp
index e1fb8c27c5..4f3990a434 100644
--- a/include/mbgl/gl/gl_helper.hpp
+++ b/include/mbgl/gl/gl_helper.hpp
@@ -1,89 +1,22 @@
 #ifndef MBGL_GL_GL_HELPER
 #define MBGL_GL_GL_HELPER
 
-#include <mbgl/gl/gl.hpp>
-
-#include <array>
-
-namespace {
+namespace mbgl {
+namespace gl {
 
-template <typename T, T (*Create)(), void (*Destroy)(const T&)>
+template <typename T>
 class Preserve {
 public:
-    Preserve() : data(Create()) {}
-    ~Preserve() { Destroy(data); }
+    inline Preserve() : data(T::Get()) {
+    }
+    inline ~Preserve() {
+        T::Set(data);
+    }
 
 private:
-    const T data;
+    const typename T::Type data;
 };
 
-inline bool getBlend() {
-    return glIsEnabled(GL_BLEND);
-}
-
-inline void setBlend(const bool& enabled) {
-    enabled ? MBGL_CHECK_ERROR(glEnable(GL_BLEND)) : MBGL_CHECK_ERROR(glDisable(GL_BLEND));
-}
-
-inline std::array<float, 4> getClearColor() {
-    std::array<float, 4> color;
-    MBGL_CHECK_ERROR(glGetFloatv(GL_COLOR_CLEAR_VALUE, color.data()));
-    return color;
-}
-
-inline void setClearColor(const std::array<float, 4>& color) {
-    MBGL_CHECK_ERROR(glClearColor(color[0], color[1], color[2], color[3]));
-}
-
-
-inline std::array<GLenum, 2> getBlendFunc() {
-    GLint func[2];
-    glGetIntegerv(GL_BLEND_SRC_ALPHA, &func[0]);
-    glGetIntegerv(GL_BLEND_DST_ALPHA, &func[1]);
-    return {{ static_cast<GLenum>(func[0]), static_cast<GLenum>(func[1]) }};
-}
-
-inline void setBlendFunc(const std::array<GLenum, 2>& func) {
-    MBGL_CHECK_ERROR(glBlendFunc(func[0], func[1]));
-}
-
-#ifndef GL_ES_VERSION_2_0
-inline std::array<double, 2> getPixelZoom() {
-    std::array<double, 2> zoom;
-    glGetDoublev(GL_ZOOM_X, &zoom[0]);
-    glGetDoublev(GL_ZOOM_Y, &zoom[1]);
-    return zoom;
-}
-
-inline void setPixelZoom(const std::array<double, 2>& func) {
-    MBGL_CHECK_ERROR(glPixelZoom(func[0], func[1]));
-}
-
-
-inline std::array<double, 4> getRasterPos() {
-    std::array<double, 4> pos;
-    MBGL_CHECK_ERROR(glGetDoublev(GL_CURRENT_RASTER_POSITION, pos.data()));
-    return pos;
-}
-
-inline void setRasterPos(const std::array<double, 4>& pos) {
-    MBGL_CHECK_ERROR(glRasterPos4d(pos[0], pos[1], pos[2], pos[3]));
-}
-#endif
-} // end anonymous namespace
-
-namespace mbgl {
-namespace gl {
-
-using PreserveBlend = Preserve<bool, getBlend, setBlend>;
-using PreserveClearColor = Preserve<std::array<float, 4>, getClearColor, setClearColor>;
-using PreserveBlendFunc = Preserve<std::array<GLenum, 2>, getBlendFunc, setBlendFunc>;
-
-#ifndef GL_ES_VERSION_2_0
-using PreservePixelZoom = Preserve<std::array<double, 2>, getPixelZoom, setPixelZoom>;
-using PreserveRasterPos = Preserve<std::array<double, 4>, getRasterPos, setRasterPos>;
-#endif
-
 } // namespace gl
 } // namespace mbgl
 
diff --git a/src/mbgl/renderer/gl_config.hpp b/include/mbgl/gl/gl_values.hpp
index 4ab1dbb268..a5d413f5af 100644
--- a/src/mbgl/renderer/gl_config.hpp
+++ b/include/mbgl/gl/gl_values.hpp
@@ -1,5 +1,5 @@
-#ifndef MBGL_RENDERER_GL_CONFIG
-#define MBGL_RENDERER_GL_CONFIG
+#ifndef MBGL_GL_GL_VALUES
+#define MBGL_GL_GL_VALUES
 
 #include <cstdint>
 #include <tuple>
@@ -10,32 +10,6 @@
 namespace mbgl {
 namespace gl {
 
-template <typename T>
-class Value {
-public:
-    inline void operator=(const typename T::Type& value) {
-        if (dirty || current != value) {
-            dirty = false;
-            current = value;
-            T::Set(current);
-        }
-    }
-
-    inline void reset() {
-        dirty = true;
-        current = T::Default;
-        T::Set(current);
-    }
-
-    inline void setDirty() {
-        dirty = true;
-    }
-
-private:
-    typename T::Type current = T::Default;
-    bool dirty = false;
-};
-
 struct ClearDepth {
     using Type = GLfloat;
     static const Type Default;
@@ -266,64 +240,37 @@ struct LineWidth {
     }
 };
 
-class Config {
-public:
-    void reset() {
-        stencilFunc.reset();
-        stencilMask.reset();
-        stencilTest.reset();
-        stencilOp.reset();
-        depthRange.reset();
-        depthMask.reset();
-        depthTest.reset();
-        depthFunc.reset();
-        blend.reset();
-        blendFunc.reset();
-        colorMask.reset();
-        clearDepth.reset();
-        clearColor.reset();
-        clearStencil.reset();
-        program.reset();
-        lineWidth.reset();
-    }
+#ifndef GL_ES_VERSION_2_0
 
-    void setDirty() {
-        stencilFunc.setDirty();
-        stencilMask.setDirty();
-        stencilTest.setDirty();
-        stencilOp.setDirty();
-        depthRange.setDirty();
-        depthMask.setDirty();
-        depthTest.setDirty();
-        depthFunc.setDirty();
-        blend.setDirty();
-        blendFunc.setDirty();
-        colorMask.setDirty();
-        clearDepth.setDirty();
-        clearColor.setDirty();
-        clearStencil.setDirty();
-        program.setDirty();
-        lineWidth.setDirty();
+struct PixelZoom {
+    struct Type { GLfloat xfactor; GLfloat yfactor; };
+    static const Type Default;
+    inline static void Set(const Type& value) {
+        MBGL_CHECK_ERROR(glPixelZoom(value.xfactor, value.yfactor));
+    }
+    inline static Type Get() {
+        Type value;
+        MBGL_CHECK_ERROR(glGetFloatv(GL_ZOOM_X, &value.xfactor));
+        MBGL_CHECK_ERROR(glGetFloatv(GL_ZOOM_Y, &value.yfactor));
+        return value;
     }
+};
 
-    Value<StencilFunc> stencilFunc;
-    Value<StencilMask> stencilMask;
-    Value<StencilTest> stencilTest;
-    Value<StencilOp> stencilOp;
-    Value<DepthRange> depthRange;
-    Value<DepthMask> depthMask;
-    Value<DepthTest> depthTest;
-    Value<DepthFunc> depthFunc;
-    Value<Blend> blend;
-    Value<BlendFunc> blendFunc;
-    Value<ColorMask> colorMask;
-    Value<ClearDepth> clearDepth;
-    Value<ClearColor> clearColor;
-    Value<ClearStencil> clearStencil;
-    Value<Program> program;
-    Value<LineWidth> lineWidth;
+struct RasterPos {
+    using Type = std::array<GLdouble, 4>;
+    static const Type Default;
+    inline static void Set(const Type& value) {
+        MBGL_CHECK_ERROR(glRasterPos4d(value[0], value[1], value[2], value[3]));
+    }
+    inline static Type Get() {
+        Type pos;
+        MBGL_CHECK_ERROR(glGetDoublev(GL_CURRENT_RASTER_POSITION, pos.data()));
+        return pos;
+    }
 };
 
+#endif
+
 } // namespace gl
 } // namespace mbgl
 
diff --git a/include/mbgl/platform/default/glfw_view.hpp b/include/mbgl/platform/default/glfw_view.hpp
index 0e46f7d87e..2f74404201 100644
--- a/include/mbgl/platform/default/glfw_view.hpp
+++ b/include/mbgl/platform/default/glfw_view.hpp
@@ -6,6 +6,7 @@
 #ifdef MBGL_USE_GLES2
 #define GLFW_INCLUDE_ES2
 #endif
+#define GL_GLEXT_PROTOTYPES
 #include <GLFW/glfw3.h>
 
 #include <atomic>
diff --git a/platform/default/glfw_view.cpp b/platform/default/glfw_view.cpp
index 375b9fd626..3173bfddee 100644
--- a/platform/default/glfw_view.cpp
+++ b/platform/default/glfw_view.cpp
@@ -1,8 +1,9 @@
+#include <mbgl/platform/default/glfw_view.hpp>
 #include <mbgl/annotation/point_annotation.hpp>
 #include <mbgl/annotation/shape_annotation.hpp>
 #include <mbgl/sprite/sprite_image.hpp>
-#include <mbgl/platform/default/glfw_view.hpp>
 #include <mbgl/gl/gl.hpp>
+#include <mbgl/gl/gl_values.hpp>
 #include <mbgl/gl/gl_helper.hpp>
 #include <mbgl/platform/log.hpp>
 #include <mbgl/util/string.hpp>
@@ -496,8 +497,8 @@ void showDebugImage(std::string name, const char *data, size_t width, size_t hei
     float scale = static_cast<float>(fbWidth) / static_cast<float>(width);
 
     {
-        gl::PreservePixelZoom pixelZoom;
-        gl::PreserveRasterPos rasterPos;
+        gl::Preserve<gl::PixelZoom> pixelZoom;
+        gl::Preserve<gl::RasterPos> rasterPos;
 
         MBGL_CHECK_ERROR(glPixelZoom(scale, -scale));
         MBGL_CHECK_ERROR(glRasterPos2f(-1.0f, 1.0f));
@@ -533,11 +534,11 @@ void showColorDebugImage(std::string name, const char *data, size_t logicalWidth
     float yScale = static_cast<float>(fbHeight) / static_cast<float>(height);
 
     {
-        gl::PreserveClearColor clearColor;
-        gl::PreserveBlend blend;
-        gl::PreserveBlendFunc blendFunc;
-        gl::PreservePixelZoom pixelZoom;
-        gl::PreserveRasterPos rasterPos;
+        gl::Preserve<gl::ClearColor> clearColor;
+        gl::Preserve<gl::Blend> blend;
+        gl::Preserve<gl::BlendFunc> blendFunc;
+        gl::Preserve<gl::PixelZoom> pixelZoom;
+        gl::Preserve<gl::RasterPos> rasterPos;
 
         MBGL_CHECK_ERROR(glClearColor(0.8, 0.8, 0.8, 1));
         MBGL_CHECK_ERROR(glClear(GL_COLOR_BUFFER_BIT));
diff --git a/src/mbgl/renderer/gl_config.cpp b/src/mbgl/gl/gl_config.cpp
index 4160ae100e..4160ae100e 100644
--- a/src/mbgl/renderer/gl_config.cpp
+++ b/src/mbgl/gl/gl_config.cpp
diff --git a/src/mbgl/gl/gl_config.hpp b/src/mbgl/gl/gl_config.hpp
new file mode 100644
index 0000000000..af373fc3f8
--- /dev/null
+++ b/src/mbgl/gl/gl_config.hpp
@@ -0,0 +1,100 @@
+#ifndef MBGL_GL_GL_CONFIG
+#define MBGL_GL_GL_CONFIG
+
+#include <cstdint>
+#include <tuple>
+#include <array>
+
+#include <mbgl/gl/gl_values.hpp>
+
+namespace mbgl {
+namespace gl {
+
+template <typename T>
+class Value {
+public:
+    inline void operator=(const typename T::Type& value) {
+        if (dirty || current != value) {
+            dirty = false;
+            current = value;
+            T::Set(current);
+        }
+    }
+
+    inline void reset() {
+        dirty = true;
+        current = T::Default;
+        T::Set(current);
+    }
+
+    inline void setDirty() {
+        dirty = true;
+    }
+
+private:
+    typename T::Type current = T::Default;
+    bool dirty = false;
+};
+
+class Config {
+public:
+    void reset() {
+        stencilFunc.reset();
+        stencilMask.reset();
+        stencilTest.reset();
+        stencilOp.reset();
+        depthRange.reset();
+        depthMask.reset();
+        depthTest.reset();
+        depthFunc.reset();
+        blend.reset();
+        blendFunc.reset();
+        colorMask.reset();
+        clearDepth.reset();
+        clearColor.reset();
+        clearStencil.reset();
+        program.reset();
+        lineWidth.reset();
+    }
+
+    void setDirty() {
+        stencilFunc.setDirty();
+        stencilMask.setDirty();
+        stencilTest.setDirty();
+        stencilOp.setDirty();
+        depthRange.setDirty();
+        depthMask.setDirty();
+        depthTest.setDirty();
+        depthFunc.setDirty();
+        blend.setDirty();
+        blendFunc.setDirty();
+        colorMask.setDirty();
+        clearDepth.setDirty();
+        clearColor.setDirty();
+        clearStencil.setDirty();
+        program.setDirty();
+        lineWidth.setDirty();
+    }
+
+    Value<StencilFunc> stencilFunc;
+    Value<StencilMask> stencilMask;
+    Value<StencilTest> stencilTest;
+    Value<StencilOp> stencilOp;
+    Value<DepthRange> depthRange;
+    Value<DepthMask> depthMask;
+    Value<DepthTest> depthTest;
+    Value<DepthFunc> depthFunc;
+    Value<Blend> blend;
+    Value<BlendFunc> blendFunc;
+    Value<ColorMask> colorMask;
+    Value<ClearDepth> clearDepth;
+    Value<ClearColor> clearColor;
+    Value<ClearStencil> clearStencil;
+    Value<Program> program;
+    Value<LineWidth> lineWidth;
+};
+
+} // namespace gl
+} // namespace mbgl
+
+#endif // MBGL_RENDERER_GL_CONFIG
diff --git a/src/mbgl/renderer/painter.hpp b/src/mbgl/renderer/painter.hpp
index 3940978835..e2949681cd 100644
--- a/src/mbgl/renderer/painter.hpp
+++ b/src/mbgl/renderer/painter.hpp
@@ -10,7 +10,7 @@
 #include <mbgl/geometry/vao.hpp>
 #include <mbgl/geometry/static_vertex_buffer.hpp>
 
-#include <mbgl/renderer/gl_config.hpp>
+#include <mbgl/gl/gl_config.hpp>
 
 #include <mbgl/style/types.hpp>