Move NullColorbuffer handling from Framebuffer to Renderer9

src/libGLESv2/Framebuffer.cpp

@@ -30,7 +30,6 @@ Framebuffer::~Framebuffer()
     mColorbufferPointer.set(NULL);
     mDepthbufferPointer.set(NULL);
     mStencilbufferPointer.set(NULL);
-    mNullColorbufferPointer.set(NULL);
 }
 
 Renderbuffer *Framebuffer::lookupRenderbuffer(GLenum type, GLuint handle) const
@@ -181,30 +180,6 @@ Renderbuffer *Framebuffer::getDepthOrStencilbuffer()
     return depthstencilbuffer;
 }
 
-Renderbuffer *Framebuffer::getNullColorbuffer()
-{
-    Renderbuffer *nullbuffer  = mNullColorbufferPointer.get();
-    Renderbuffer *depthbuffer = getDepthbuffer();
-
-    if (!depthbuffer)
-    {
-        ERR("Unexpected null depthbuffer for depth-only FBO.");
-        return NULL;
-    }
-
-    GLsizei width  = depthbuffer->getWidth();
-    GLsizei height = depthbuffer->getHeight();
-
-    if (!nullbuffer ||
-        width != nullbuffer->getWidth() || height != nullbuffer->getHeight())
-    {
-        nullbuffer = new Renderbuffer(mRenderer, 0, new Colorbuffer(mRenderer, width, height, GL_NONE, 0));
-        mNullColorbufferPointer.set(nullbuffer);
-    }
-
-    return nullbuffer;
-}
-
 GLenum Framebuffer::getColorbufferType()
 {
     return mColorbufferType;

src/libGLESv2/Framebuffer.h

@@ -51,7 +51,6 @@ class Framebuffer
     Renderbuffer *getDepthbuffer();
     Renderbuffer *getStencilbuffer();
     Renderbuffer *getDepthOrStencilbuffer();
-    Renderbuffer *getNullColorbuffer();
 
     GLenum getColorbufferType();
     GLenum getDepthbufferType();
@@ -76,8 +75,6 @@ class Framebuffer
     GLenum mStencilbufferType;
     BindingPointer<Renderbuffer> mStencilbufferPointer;
 
-    BindingPointer<Renderbuffer> mNullColorbufferPointer;
-
     rx::Renderer *mRenderer;
 
   private:

src/libGLESv2/renderer/Renderer9.cpp

@@ -95,6 +95,15 @@ Renderer9::Renderer9(egl::Display *display, HDC hDc, bool softwareDevice) : Rend
     mVertexDataManager = NULL;
     mIndexDataManager = NULL;
     mLineLoopIB = NULL;
+
+    mMaxNullColorbufferLRU = 0;
+    for (int i = 0; i < NUM_NULL_COLORBUFFER_CACHE_ENTRIES; i++)
+    {
+        mNullColorbufferCache[i].lruCount = 0;
+        mNullColorbufferCache[i].width = 0;
+        mNullColorbufferCache[i].height = 0;
+        mNullColorbufferCache[i].buffer = NULL;
+    }
 }
 
 Renderer9::~Renderer9()
@@ -991,6 +1000,51 @@ bool Renderer9::applyPrimitiveType(GLenum mode, GLsizei count)
     return mPrimitiveCount > 0;
 }
 
+
+gl::Renderbuffer *Renderer9::getNullColorbuffer(gl::Renderbuffer *depthbuffer)
+{
+    if (!depthbuffer)
+    {
+        ERR("Unexpected null depthbuffer for depth-only FBO.");
+        return NULL;
+    }
+
+    GLsizei width  = depthbuffer->getWidth();
+    GLsizei height = depthbuffer->getHeight();
+
+    // search cached nullcolorbuffers
+    for (int i = 0; i < NUM_NULL_COLORBUFFER_CACHE_ENTRIES; i++)
+    {
+        if (mNullColorbufferCache[i].buffer != NULL &&
+            mNullColorbufferCache[i].width == width &&
+            mNullColorbufferCache[i].height == height)
+        {
+            mNullColorbufferCache[i].lruCount = ++mMaxNullColorbufferLRU;
+            return mNullColorbufferCache[i].buffer;
+        }
+    }
+
+    gl::Renderbuffer *nullbuffer = new gl::Renderbuffer(this, 0, new gl::Colorbuffer(this, width, height, GL_NONE, 0));
+
+    // add nullbuffer to the cache
+    NullColorbufferCacheEntry *oldest = &mNullColorbufferCache[0];
+    for (int i = 1; i < NUM_NULL_COLORBUFFER_CACHE_ENTRIES; i++)
+    {
+        if (mNullColorbufferCache[i].lruCount < oldest->lruCount)
+        {
+            oldest = &mNullColorbufferCache[i];
+        }
+    }
+
+    delete oldest->buffer;
+    oldest->buffer = nullbuffer;
+    oldest->lruCount = ++mMaxNullColorbufferLRU;
+    oldest->width = width;
+    oldest->height = height;
+
+    return nullbuffer;
+}
+
 bool Renderer9::applyRenderTarget(gl::Framebuffer *framebuffer)
 {
     // if there is no color attachment we must synthesize a NULL colorattachment
@@ -1002,7 +1056,7 @@ bool Renderer9::applyRenderTarget(gl::Framebuffer *framebuffer)
     }
     else
     {
-        renderbufferObject = framebuffer->getNullColorbuffer();
+        renderbufferObject = getNullColorbuffer(framebuffer->getDepthbuffer());
     }
     if (!renderbufferObject)
     {
@@ -1603,6 +1657,13 @@ void Renderer9::releaseDeviceResources()
 
     delete mLineLoopIB;
     mLineLoopIB = NULL;
+
+    for (int i = 0; i < NUM_NULL_COLORBUFFER_CACHE_ENTRIES; i++)
+    {
+        delete mNullColorbufferCache[i].buffer;
+        mNullColorbufferCache[i].buffer = NULL;
+    }
+
 }
 
 

src/libGLESv2/renderer/Renderer9.h

@@ -178,6 +178,7 @@ class Renderer9 : public Renderer
 
     void getMultiSampleSupport(D3DFORMAT format, bool *multiSampleArray);
     bool copyToRenderTarget(IDirect3DSurface9 *dest, IDirect3DSurface9 *source, bool fromManaged);
+    gl::Renderbuffer *getNullColorbuffer(gl::Renderbuffer *depthbuffer);
 
     D3DPOOL getBufferPool(DWORD usage) const;
 
@@ -267,6 +268,17 @@ class Renderer9 : public Renderer
 
     IndexDataManager *mIndexDataManager;
     StreamingIndexBuffer *mLineLoopIB;
+
+    enum { NUM_NULL_COLORBUFFER_CACHE_ENTRIES = 12 };
+    struct NullColorbufferCacheEntry
+    {
+        UINT lruCount;
+        int width;
+        int height;
+        gl::Renderbuffer *buffer;
+    } mNullColorbufferCache[NUM_NULL_COLORBUFFER_CACHE_ENTRIES];
+    UINT mMaxNullColorbufferLRU;
+
 };
 
 }