add different meshes with different primitive types & without or with index buffer

refactor background color to main

GDP/D3D9/main.cpp

@@ -36,6 +36,9 @@ int WINAPI WinMain(
 	error = d3d.init(window.getWindowHandle(), width, height, isFullscreen);
 	CheckError(error);
 
+	// set render states
+	d3d.getDevice()->SetRenderState(D3DRS_CULLMODE, D3DCULL_CCW);
+
 	// 3. create a mesh
 	Mesh mesh = {};
 	error = mesh.init(d3d.getDevice());