[core] Render fill-extrusion layers (#8431)

1 files changed, 20 insertions, 1 deletions

diff --git a/src/mbgl/util/offscreen_texture.cpp b/src/mbgl/util/offscreen_texture.cpp
index 56ef60b15c..e719ac566e 100644
--- a/src/mbgl/util/offscreen_texture.cpp
+++ b/src/mbgl/util/offscreen_texture.cpp
@@ -14,12 +14,13 @@ public:
 
     void bind() {
         if (!framebuffer) {
-            texture = context.createTexture(size);
+            texture = context.createTexture(size, gl::TextureFormat::RGBA);
             framebuffer = context.createFramebuffer(*texture);
         } else {
             context.bindFramebuffer = framebuffer->framebuffer;
         }
 
+        context.activeTexture = 0;
         context.viewport = { 0, 0, size };
     }
 
@@ -36,6 +37,20 @@ public:
         return size;
     }
 
+    void bindRenderbuffers(gl::TextureUnit unit) {
+        if (!framebuffer) {
+            texture = context.createTexture(size, gl::TextureFormat::RGBA, unit);
+            gl::Renderbuffer<gl::RenderbufferType::DepthComponent> depthTarget = context.createRenderbuffer<gl::RenderbufferType::DepthComponent>(size);
+            framebuffer = context.createFramebuffer(*texture, depthTarget);
+
+        } else {
+            context.bindFramebuffer = framebuffer->framebuffer;
+        }
+
+        context.activeTexture = unit;
+        context.viewport = { 0, 0, size };
+    }
+
 private:
     gl::Context& context;
     const Size size;
@@ -66,4 +81,8 @@ const Size& OffscreenTexture::getSize() const {
     return impl->getSize();
 }
 
+void OffscreenTexture::bindRenderbuffers(gl::TextureUnit unit) {
+    impl->bindRenderbuffers(unit);
+}
+
 } // namespace mbgl