[core] refactor RendererBackend

3 files changed, 56 insertions, 47 deletions

diff --git a/platform/android/src/android_renderer_backend.cpp b/platform/android/src/android_renderer_backend.cpp
index 52a9a93170..09c9e85ad5 100755
--- a/platform/android/src/android_renderer_backend.cpp
+++ b/platform/android/src/android_renderer_backend.cpp
@@ -1,6 +1,8 @@
 #include "android_renderer_backend.hpp"
 
+#include <mbgl/gfx/backend_scope.hpp>
 #include <mbgl/gl/context.hpp>
+#include <mbgl/gl/renderable_resource.hpp>
 
 #include <EGL/egl.h>
 
@@ -9,18 +11,27 @@
 namespace mbgl {
 namespace android {
 
-/**
- * From mbgl::View
- */
-void AndroidRendererBackend::bind() {
-    assert(gfx::BackendScope::exists());
-    setFramebufferBinding(0);
-    setViewport(0, 0, getFramebufferSize());
+class AndroidGLRenderableResource final : public mbgl::gl::RenderableResource {
+public:
+    AndroidGLRenderableResource(AndroidRendererBackend& backend_) : backend(backend_) {
+    }
+
+    void bind() override {
+        assert(gfx::BackendScope::exists());
+        backend.setFramebufferBinding(0);
+        backend.setViewport(0, 0, backend.getSize());
+    }
+
+private:
+    AndroidRendererBackend& backend;
+};
+
+AndroidRendererBackend::AndroidRendererBackend()
+    : mbgl::gfx::Renderable({ 64, 64 }, std::make_unique<AndroidGLRenderableResource>(*this)) {
 }
 
-/**
- * From mbgl::RendererBackend.
- */
+AndroidRendererBackend::~AndroidRendererBackend() = default;
+
 gl::ProcAddress AndroidRendererBackend::getExtensionFunctionPointer(const char* name) {
     assert(gfx::BackendScope::exists());
     return eglGetProcAddress(name);
@@ -28,34 +39,26 @@ gl::ProcAddress AndroidRendererBackend::getExtensionFunctionPointer(const char*
 
 void AndroidRendererBackend::updateViewPort() {
     assert(gfx::BackendScope::exists());
-    setViewport(0, 0, getFramebufferSize());
+    setViewport(0, 0, size);
 }
 
 void AndroidRendererBackend::resizeFramebuffer(int width, int height) {
-    fbWidth = width;
-    fbHeight = height;
+    size = { static_cast<uint32_t>(width), static_cast<uint32_t>(height) };
 }
 
-PremultipliedImage AndroidRendererBackend::readFramebuffer() const {
+PremultipliedImage AndroidRendererBackend::readFramebuffer() {
     assert(gfx::BackendScope::exists());
-    return RendererBackend::readFramebuffer(getFramebufferSize());
-}
-
-mbgl::Size AndroidRendererBackend::getFramebufferSize() const {
-    return { static_cast<uint32_t>(fbWidth), static_cast<uint32_t>(fbHeight) };
+    return gl::RendererBackend::readFramebuffer(size);
 }
 
-/**
- * From mbgl::RendererBackend.
- */
 void AndroidRendererBackend::updateAssumedState() {
     assumeFramebufferBinding(0);
-    assumeViewport(0, 0, getFramebufferSize());
+    assumeViewport(0, 0, size);
 }
 
 void AndroidRendererBackend::markContextLost() {
     if (context) {
-        context->setCleanupOnDestruction(false);
+        getGLContext().setCleanupOnDestruction(false);
     }
 }
 
diff --git a/platform/android/src/android_renderer_backend.hpp b/platform/android/src/android_renderer_backend.hpp
index d2c100dcc1..f06f38e688 100755
--- a/platform/android/src/android_renderer_backend.hpp
+++ b/platform/android/src/android_renderer_backend.hpp
@@ -1,40 +1,42 @@
 #pragma once
 
-#include <mbgl/renderer/renderer_backend.hpp>
+#include <mbgl/gfx/renderable.hpp>
+#include <mbgl/gl/renderer_backend.hpp>
 
 namespace mbgl {
 namespace android {
 
-class AndroidRendererBackend : public RendererBackend {
+class AndroidRendererBackend : public gl::RendererBackend, public mbgl::gfx::Renderable {
 public:
+    AndroidRendererBackend();
+    ~AndroidRendererBackend() override;
 
-    // mbgl::RendererBackend //
-    void bind() override;
-    void updateAssumedState() override;
-    mbgl::Size getFramebufferSize() const override;
+    void updateViewPort();
 
-    // Ensures the current context is not
-    // cleaned up when destroyed
+    // Ensures the current context is not cleaned up when destroyed
     void markContextLost();
 
-    void updateViewPort();
-
     void resizeFramebuffer(int width, int height);
-    PremultipliedImage readFramebuffer() const;
-
-protected:
-    // mbgl::RendererBackend //
-    gl::ProcAddress getExtensionFunctionPointer(const char*) override;
-    void activate() override {};
-    void deactivate() override {};
+    PremultipliedImage readFramebuffer();
 
+    // mbgl::gfx::RendererBackend implementation
+public:
+    mbgl::gfx::Renderable& getDefaultRenderable() override {
+        return *this;
+    }
 
-private:
-
-    // Minimum texture size according to OpenGL ES 2.0 specification.
-    int fbWidth = 64;
-    int fbHeight = 64;
-
+protected:
+    void activate() override {
+        // no-op
+    }
+    void deactivate() override {
+        // no-op
+    }
+
+    // mbgl::gl::RendererBackend implementation
+protected:
+    mbgl::gl::ProcAddress getExtensionFunctionPointer(const char*) override;
+    void updateAssumedState() override;
 };
 
 } // namespace android
diff --git a/platform/android/src/map_renderer.cpp b/platform/android/src/map_renderer.cpp
index f0273cee50..7fefa457b1 100644
--- a/platform/android/src/map_renderer.cpp
+++ b/platform/android/src/map_renderer.cpp
@@ -1,6 +1,7 @@
 #include "map_renderer.hpp"
 
 #include <mbgl/renderer/renderer.hpp>
+#include <mbgl/gfx/backend_scope.hpp>
 #include <mbgl/util/shared_thread_pool.hpp>
 #include <mbgl/util/run_loop.hpp>
 
@@ -159,6 +160,9 @@ void MapRenderer::onSurfaceCreated(JNIEnv&) {
     // Lock as the initialization can come from the main thread or the GL thread first
     std::lock_guard<std::mutex> lock(initialisationMutex);
 
+    // The GL context is already active if get a new surface.
+    gfx::BackendScope backendGuard { *backend, gfx::BackendScope::ScopeType::Implicit };
+
     // The android system will have already destroyed the underlying
     // GL resources if this is not the first initialization and an
     // attempt to clean them up will fail