Hi,

I played around with the order af drawing stuff and setting states in my engine.

There are 3 main to be rendered things:

1 - opaque objects

2 - blended objects

3 - skybox

Preferably I want to render things in that order, but when I do this, the blended objects disappear/ are not visible.

If I switch 3 and 2, skybox first, then blended objects, it looks all fine.

Does someone have an idea why this happens/ which state I'm overlooking?

Or maybe the order 1, 3 is 2 is better anyway? (and why?)

Here's the code, working:

	/** OPAQUE: RENDER SCENE USING BASE UBERSHADER **/
	mStateMachine.SetRenderState(D3DRS_ZWRITEENABLE, TRUE);
	mStateMachine.SetRenderState(D3DRS_ALPHABLENDENABLE, FALSE);
	mStateMachine.SetSamplerState(0, D3DSAMP_ADDRESSU, D3DTADDRESS_WRAP);
	mStateMachine.SetSamplerState(0, D3DSAMP_ADDRESSV, D3DTADDRESS_WRAP);

	if(!RenderScene(*pD3dscene, "SingleTexTech", mRenderQueue.GetRefRenderablesOpaque(), mRenderQueue.GetRefBucketOpaque())) return false;
	
	/** RENDER SKYBOX **/ 
	if(pD3dscene->HasSkybox())
	{
		if(!pD3dscene->mSkyBox.Render(pCam->GetPosition(), *pCam)) return false;
		mStateMachine.SetRenderState(D3DRS_ALPHABLENDENABLE, FALSE);
		mStateMachine.SetRenderState(D3DRS_ZWRITEENABLE, FALSE);										
		mStateMachine.SetRenderState(D3DRS_CULLMODE, D3DCULL_CW);
		mStateMachine.SetSamplerState(0, D3DSAMP_ADDRESSU, D3DTADDRESS_MIRROR);
		mStateMachine.SetSamplerState(0, D3DSAMP_ADDRESSV, D3DTADDRESS_MIRROR);
	}

	/** BLENDED: RENDER SCENE USING UBERSHADER **/
	mStateMachine.SetRenderState(D3DRS_CULLMODE, D3DCULL_CCW);
	mStateMachine.SetRenderState(D3DRS_ZWRITEENABLE, FALSE);
	mStateMachine.SetRenderState(D3DRS_ALPHABLENDENABLE, TRUE);

	if(!RenderScene(*pD3dscene, "SingleTexTech", mRenderQueue.GetRefRenderablesBlended(), mRenderQueue.GetRefBucketBlendedSorted())) return false;

And not working (blended objects first):

	/** OPAQUE: RENDER SCENE USING BASE UBERSHADER **/
	mStateMachine.SetRenderState(D3DRS_ZWRITEENABLE, TRUE);
	mStateMachine.SetRenderState(D3DRS_ALPHABLENDENABLE, FALSE);
	mStateMachine.SetSamplerState(0, D3DSAMP_ADDRESSU, D3DTADDRESS_WRAP);
	mStateMachine.SetSamplerState(0, D3DSAMP_ADDRESSV, D3DTADDRESS_WRAP);

	if(!RenderScene(*pD3dscene, "SingleTexTech", mRenderQueue.GetRefRenderablesOpaque(), mRenderQueue.GetRefBucketOpaque())) return false;

	/** BLENDED: RENDER SCENE USING UBERSHADER **/
	mStateMachine.SetRenderState(D3DRS_CULLMODE, D3DCULL_CCW);
	mStateMachine.SetRenderState(D3DRS_ZWRITEENABLE, FALSE);
	mStateMachine.SetRenderState(D3DRS_ALPHABLENDENABLE, TRUE);

	if(!RenderScene(*pD3dscene, "SingleTexTech", mRenderQueue.GetRefRenderablesBlended(), mRenderQueue.GetRefBucketBlendedSorted())) return false;

	/** RENDER SKYBOX **/ 
	if(pD3dscene->HasSkybox())
	{
		if(!pD3dscene->mSkyBox.Render(pCam->GetPosition(), *pCam)) return false;
		mStateMachine.SetRenderState(D3DRS_ALPHABLENDENABLE, FALSE);
		mStateMachine.SetRenderState(D3DRS_ZWRITEENABLE, FALSE);										
		mStateMachine.SetRenderState(D3DRS_CULLMODE, D3DCULL_CW);
		mStateMachine.SetSamplerState(0, D3DSAMP_ADDRESSU, D3DTADDRESS_MIRROR);
		mStateMachine.SetSamplerState(0, D3DSAMP_ADDRESSV, D3DTADDRESS_MIRROR);
	}

Actually with the code above, the blended objects are not visible at all.

I only get them visible in that rendering order, when I set D3DRS_ZWRITEENABLE to TRUE (instead of false). But then blending get's messed up.

Playing around so far didn't bring me the effect you're describing.

For now, I'll stick to opaque, skybox, transparent, since that gives the expected result (still don't understand though why I can't get the blended objects visible when rendering the skybox last). Switching skybox to 1 and then opaque works, but gives no difference (because I disable Z-write Always when drawing the skybox, and in the skybox shader is set pos.Z to pos.W so it's Always 1.