private QuadBatch RenderPasses(DisplayObject obj, RenderSupport support, bool intoCache)
{
Texture cacheTexture = null;
Stage stage = obj.Stage;
float scale = Resolution;
if (stage == null)
{
throw new InvalidOperationException("Filtered object must be on the stage.");
}
// the bounds of the object in stage coordinates
Rectangle boundsPOT;
Rectangle bounds;
CalcBounds(obj, stage, scale, !intoCache, out bounds, out boundsPOT);
if (bounds.IsEmpty())
{
DisposePassTextures();
return intoCache ? new QuadBatch() : null;
}
UpdateBuffers(boundsPOT);
UpdatePassTextures((int)boundsPOT.Width, (int)boundsPOT.Height, scale);
support.FinishQuadBatch();
support.AddDrawCalls(NumPasses);
support.PushState(Matrix.Create(), 1.0f, BlendMode.AUTO);
// save original projection matrix and render target
_projMatrix.CopyFromMatrix(support.ProjectionMatrix);
Texture previousRenderTarget = support.RenderTarget;
// use cache?
if (intoCache)
{
cacheTexture = CreateTexture((int)boundsPOT.Width, (int)boundsPOT.Height, scale);
}
// draw the original object into a texture
support.RenderTarget = _passTextures[0];
SparrowSharpApp.Context.ScissorBox = null; // we want the entire texture cleared
support.Clear();
support.BlendMode = BlendMode.NORMAL;
support.SetupOrthographicProjection(boundsPOT.Left, boundsPOT.Right, boundsPOT.Bottom, boundsPOT.Top);
obj.Render(support);
support.FinishQuadBatch();
// prepare drawing of actual filter passes
support.ApplyBlendMode(true);
support.ModelViewMatrix.Identity();
support.PushClipRect(bounds);
GL.BindBuffer (BufferTarget.ArrayBuffer, _vertexBufferName);
GL.BindBuffer (BufferTarget.ElementArrayBuffer, _indexBufferName);
GL.EnableVertexAttribArray (VertexPosID);
GL.VertexAttribPointer (VertexPosID, 2, VertexAttribPointerType.Float, false, Vertex.SIZE, (IntPtr)Vertex.POSITION_OFFSET);
GL.EnableVertexAttribArray (TexCoordsID);
GL.VertexAttribPointer (TexCoordsID, 2, VertexAttribPointerType.Float, false, Vertex.SIZE, (IntPtr)Vertex.TEXTURE_OFFSET);
// draw all passes
for (int i = 0; i < NumPasses; ++i)
{
if (i < NumPasses - 1)
{ // intermediate pass
// draw into pass texture
support.RenderTarget = PassTextureForPass(i + 1);
support.Clear();
}
else
{ // final pass
if (intoCache)
{
// draw into cache texture
support.RenderTarget = cacheTexture;
support.Clear();
}
else
{
// draw into back buffer, at original (stage) coordinates
support.RenderTarget = previousRenderTarget;
support.ProjectionMatrix = _projMatrix;
support.ModelViewMatrix.Translate(OffsetX, OffsetY);
support.BlendMode = obj.BlendMode;
support.ApplyBlendMode(true);
}
}
Texture passTexture = PassTextureForPass(i);
GL.ActiveTexture (TextureUnit.Texture0);
GL.BindTexture (TextureTarget.Texture2D, passTexture.Name);
ActivateWithPass (i, passTexture, support.MvpMatrix);
GL.DrawElements (BeginMode.Triangles, 6, DrawElementsType.UnsignedShort, IntPtr.Zero);
DeactivateWithPass(i, passTexture);
}
GL.DisableVertexAttribArray(VertexPosID);
GL.DisableVertexAttribArray(TexCoordsID);
support.PopState();
support.PopClipRect();
QuadBatch cache = null;
if (intoCache)
{
// restore support settings
support.RenderTarget = previousRenderTarget;
support.ProjectionMatrix = _projMatrix;
// Create an image containing the cache. To have a display object that contains
// the filter output in object coordinates, we wrap it in a QuadBatch: that way,
// we can modify it with a transformation matrix.
cache = new QuadBatch();
Image image = new Image(cacheTexture);
Matrix matrix = stage.TransformationMatrixToSpace(obj);
// Note: the next line was originally:
// matrix.Translate (bounds.X + OffsetX, bounds.Y + OffsetY);
// this seems like a sparrow-s bug; fix is from Starling
matrix.PrependTranslation(bounds.X + OffsetX, bounds.Top + OffsetY);
cache.AddQuad(image, 1.0f, BlendMode.AUTO, matrix);
}
return cache;
}
override public void Render(RenderSupport support)
{
foreach (DisplayObject child in _children)
{
if (child.HasVisibleArea)
{
support.PushState(child.TransformationMatrix, child.Alpha, child.BlendMode);
if (child.Filter != null)
{
child.Filter.RenderObject(child, support);
}
else
{
child.Render(support);
}
support.PopState();
}
}
}