public void Perform(PrimitiveType type)
{
//Make sure the render target is binded
RenderTarget.Bind(Target);
//Set render target
if (state.Target != Target)
{
state.Target = Target;
if (Target != null)
{
GL.Viewport(0, 0, Target.Width, Target.Height);
}
else
{
GL.Viewport(0, 0, Screen.DrawWidth, Screen.DrawHeight);
}
}
//Set blend mode
if (Blend)
{
if (!state.Blend || !BlendMode.Equals(ref state.BlendMode))
{
if (!state.Blend)
{
state.Blend = true;
GL.Enable(EnableCap.Blend);
}
state.BlendMode = BlendMode;
GL.BlendEquation(BlendMode.Eq);
GL.BlendFunc(BlendMode.Src, BlendMode.Dst);
}
}
else if (state.Blend)
{
state.Blend = false;
GL.Disable(EnableCap.Blend);
}
//TODO: might be nice if clipping actually used proper coordinates,
//but we'll have to make it *always* update, and use the Target's height
//Set clipping
if (Clip)
{
if (!state.Clip)
{
state.Clip = true;
GL.Enable(EnableCap.ScissorTest);
}
//GL.Scissor(ClipRect.X, ClipRect.Y, ClipRect.W, ClipRect.H);
GL.Scissor(ClipRect.X, (Target != null ? Target.Height : Screen.DrawHeight) - ClipRect.MaxY, ClipRect.W, ClipRect.H);
}
else if (state.Clip)
{
state.Clip = false;
GL.Disable(EnableCap.ScissorTest);
}
//We need a material and a valid mesh in order to draw
if (Mesh == null || Material == null || Mesh.uploadedIndexCount == 0 || Mesh.uploadedVertexCount == 0)
{
return;
}
//Sync the shader's state with the material
bool uploadAll = false;
if (state.Material != Material)
{
if (state.Material == null || state.Material.Shader != Material.Shader)
{
GL.UseProgram(Material.Shader.id);
uploadAll = true;
}
state.Material = Material;
}
Material.Upload(uploadAll);
//Bind the vertex array
if (state.Mesh != Mesh || Mesh.dirty)
{
GL.BindVertexArray(Mesh.vaoID);
GL.BindBuffer(BufferTarget.Array, Mesh.arrayID);
GL.BindBuffer(BufferTarget.ElementArray, Mesh.elementID);
state.Mesh = Mesh;
Mesh.dirty = false;
}
//Draw the mesh triangles
GL.DrawElements(type, Mesh.uploadedIndexCount, IndexType.UnsignedInt, IntPtr.Zero);
}
