Stop leaking textures and framebuffers in the OpenGL backend.

Closes #264.

Possibly addresses #286.

gl/src/lib.rs

@@ -456,12 +456,15 @@ impl Device for GLDevice {
     }
 
     #[inline]
-    fn destroy_framebuffer(&self, framebuffer: Self::Framebuffer) -> Self::Texture {
+    fn destroy_framebuffer(&self, mut framebuffer: Self::Framebuffer) -> Self::Texture {
         let texture = GLTexture {
             gl_texture: framebuffer.texture.gl_texture,
             size: framebuffer.texture.size,
             format: framebuffer.texture.format,
         };
+        unsafe {
+            gl::DeleteFramebuffers(1, &mut framebuffer.gl_framebuffer); ck();
+        }
         mem::forget(framebuffer);
         texture
     }
@@ -991,6 +994,14 @@ pub struct GLTexture {
     pub format: TextureFormat,
 }
 
+impl Drop for GLTexture {
+    fn drop(&mut self) {
+        unsafe {
+            gl::DeleteTextures(1, &mut self.gl_texture); ck();
+        }
+    }
+}
+
 pub struct GLTimerQuery {
     gl_query: GLuint,
 }

renderer/src/gpu/renderer.rs

@@ -1140,12 +1140,11 @@ impl<D> TextureCache<D> where D: Device {
     fn create_texture(&mut self, device: &mut D, format: TextureFormat, size: Vector2I)
                       -> D::Texture {
         for index in 0..self.textures.len() {
-            if device.texture_size(&self.textures[index]) != size ||
+            if device.texture_size(&self.textures[index]) == size &&
-                    device.texture_format(&self.textures[index]) != format {
+                    device.texture_format(&self.textures[index]) == format {
-                continue;
-            }
                 return self.textures.remove(index);
             }
+        }
 
         device.create_texture(format, size)
     }