1 files changed, 53 insertions, 5 deletions
diff --git a/src/mbgl/renderer/layers/render_custom_layer.cpp b/src/mbgl/renderer/layers/render_custom_layer.cpp
index add3d0d5ad..4d6084075d 100644
--- a/src/mbgl/renderer/layers/render_custom_layer.cpp
+++ b/src/mbgl/renderer/layers/render_custom_layer.cpp
@@ -1,15 +1,27 @@
 #include <mbgl/renderer/layers/render_custom_layer.hpp>
+#include <mbgl/renderer/painter.hpp>
+#include <mbgl/renderer/paint_parameters.hpp>
 #include <mbgl/style/layers/custom_layer_impl.hpp>
-#include <mbgl/renderer/bucket.hpp>
+#include <mbgl/map/transform_state.hpp>
+#include <mbgl/map/backend_scope.hpp>
 
 namespace mbgl {
 
+using namespace style;
+
 RenderCustomLayer::RenderCustomLayer(Immutable<style::CustomLayer::Impl> _impl)
-    : RenderLayer(style::LayerType::Custom, _impl) {
+    : RenderLayer(LayerType::Custom, _impl) {
+}
+
+RenderCustomLayer::~RenderCustomLayer() {
+    assert(BackendScope::exists());
+    if (initialized && impl().deinitializeFn) {
+        impl().deinitializeFn(impl().context);
+    }
 }
 
-const style::CustomLayer::Impl& RenderCustomLayer::impl() const {
-    return static_cast<const style::CustomLayer::Impl&>(*baseImpl);
+const CustomLayer::Impl& RenderCustomLayer::impl() const {
+    return static_cast<const CustomLayer::Impl&>(*baseImpl);
 }
 
 void RenderCustomLayer::evaluate(const PropertyEvaluationParameters&) {
@@ -24,5 +36,41 @@ std::unique_ptr<Bucket> RenderCustomLayer::createBucket(const BucketParameters&,
     assert(false);
     return nullptr;
 }
-    
+
+void RenderCustomLayer::render(Painter& painter, PaintParameters& paintParameters, RenderSource*) {
+    if (!initialized) {
+        assert(impl().initializeFn);
+        impl().initializeFn(impl().context);
+        initialized = true;
+    }
+
+    gl::Context& context = painter.context;
+    const TransformState& state = painter.state;
+
+    // Reset GL state to a known state so the CustomLayer always has a clean slate.
+    context.vertexArrayObject = 0;
+    context.setDepthMode(painter.depthModeForSublayer(0, gl::DepthMode::ReadOnly));
+    context.setStencilMode(gl::StencilMode::disabled());
+    context.setColorMode(painter.colorModeForRenderPass());
+
+    CustomLayerRenderParameters parameters;
+
+    parameters.width = state.getSize().width;
+    parameters.height = state.getSize().height;
+    parameters.latitude = state.getLatLng().latitude();
+    parameters.longitude = state.getLatLng().longitude();
+    parameters.zoom = state.getZoom();
+    parameters.bearing = -state.getAngle() * util::RAD2DEG;
+    parameters.pitch = state.getPitch();
+    parameters.fieldOfView = state.getFieldOfView();
+
+    assert(impl().renderFn);
+    impl().renderFn(impl().context, parameters);
+
+    // Reset the view back to our original one, just in case the CustomLayer changed
+    // the viewport or Framebuffer.
+    paintParameters.view.bind();
+    context.setDirtyState();
+}
+
 } // namespace mbgl