public void Draw(MTKView view)
{
// Create a new command buffer for each renderpass to the current drawable
IMTLCommandBuffer commandBuffer = commandQueue.CommandBuffer();
// Call the view's completion handler which is required by the view since it will signal its semaphore and set up the next buffer
var drawable = view.CurrentDrawable;
// Obtain a renderPassDescriptor generated from the view's drawable textures
MTLRenderPassDescriptor renderPassDescriptor = view.CurrentRenderPassDescriptor;
// If we have a valid drawable, begin the commands to render into it
if (renderPassDescriptor != null)
{
// Create a render command encoder so we can render into something
IMTLRenderCommandEncoder renderEncoder = commandBuffer.CreateRenderCommandEncoder(renderPassDescriptor);
// First Draw
var time = clock.ElapsedMilliseconds / 1000.0f;
var viewProj = Matrix4.Mult(this.view, this.proj);
var worldViewProj = Matrix4.CreateRotationX(time) * Matrix4.CreateRotationY(time * 2) * Matrix4.CreateRotationZ(time * .7f) * viewProj;
param.WorldViewProjection = Matrix4.Transpose(worldViewProj);
param.IsTextured = true;
SetConstantBuffer(this.param, this.constantBuffer1);
// Set context state
renderEncoder.SetRenderPipelineState(pipelineState);
renderEncoder.SetFrontFacingWinding(MTLWinding.Clockwise);
renderEncoder.SetCullMode(MTLCullMode.None);
renderEncoder.SetStencilReferenceValue(0);
renderEncoder.SetDepthStencilState(depthStencilState1);
renderEncoder.SetVertexBuffer(vertexBuffer, 0, 0);
renderEncoder.SetFragmentTexture(this.texture, 0);
renderEncoder.SetFragmentSamplerState(this.sampler, 0);
renderEncoder.SetVertexBuffer(constantBuffer1, (nuint)Marshal.SizeOf(this.param), 1);
renderEncoder.SetFragmentBuffer(constantBuffer1, (nuint)Marshal.SizeOf(this.param), 1);
// Tell the render context we want to draw our primitives
renderEncoder.DrawPrimitives(MTLPrimitiveType.Triangle, 0, (nuint)vertexData.Length);
// Second Draw
// Set constant buffer
param.IsTextured = false;
worldViewProj = Matrix4.CreateRotationX(time) * Matrix4.CreateRotationY(time * 2) * Matrix4.CreateRotationZ(time * .7f) * Matrix4.Scale(1.04f) * viewProj;
param.WorldViewProjection = Matrix4.Transpose(worldViewProj);
SetConstantBuffer(this.param, constantBuffer2);
renderEncoder.SetStencilReferenceValue(1);
renderEncoder.SetDepthStencilState(depthStencilState2);
renderEncoder.SetVertexBuffer(constantBuffer2, (nuint)Marshal.SizeOf(this.param), 1);
renderEncoder.SetFragmentBuffer(constantBuffer2, (nuint)Marshal.SizeOf(this.param), 1);
// Tell the render context we want to draw our primitives
renderEncoder.DrawPrimitives(MTLPrimitiveType.Triangle, 0, (nuint)vertexData.Length);
// We're done encoding commands
renderEncoder.EndEncoding();
// Schedule a present once the framebuffer is complete using the current drawable
commandBuffer.PresentDrawable(drawable);
}
// Finalize rendering here & push the command buffer to the GPU
commandBuffer.Commit();
}