Jump to content

View more

Image of the Day

Working on an auto spawn system. #gamedev #indiedev #screenshotsaturday https://t.co/Mm2kfekz7b
IOTD | Top Screenshots

The latest, straight to your Inbox.

Subscribe to GameDev.net Direct to receive the latest updates and exclusive content.


Sign up now

Calculating Far Frustum Corners in Pixel Shader

4: Adsense

Old topic!

Guest, the last post of this topic is over 60 days old and at this point you may not reply in this topic. If you wish to continue this conversation start a new topic.


  • You cannot reply to this topic
2 replies to this topic

#1 TiagoCosta   Members   

3655
Like
0Likes
Like

Posted 04 May 2012 - 04:09 PM

I'm trying to calculate the far frustum corners position in view space in the pixel shader but it's not working...

I'm following MJP's article:

So I draw a fullscreen quad with the following vertices:

PVertex vertices[] = 
{
     PVertex(-1.0f, -1.0f, 1.0f),
     PVertex(-1.0f, 1.0f, 1.0f),
     PVertex(1.0f, 1.0f, 1.0f),
     PVertex(1.0f, -1.0f, 1.0f)
};

And the vertex shader looks like this:

VS_OUT VS(VS_IN vIn)
{
VS_OUT vOut;

vOut.posH = float4(vIn.posL, 1.0f);

#ifdef DIRECTIONAL_LIGHT
vOut.positionVS = mul(float4(vIn.posL, 1.0f), gInvView);
#else
vOut.positionVS = mul(float4(vIn.posL, 1.0f), gWorld).xyz;
#endif

return vOut;
}

However positionVS gets values like: (-0.736, -0.414, 1.0); which is far from a far frustum corner position in view space...

#2 jameszhao00   Members   

271
Like
1Likes
Like

Posted 04 May 2012 - 04:38 PM

(-1, -1, 1), ... are in NDC space.

NDC -> VS

float3 ndc = //....
float4 hcs = float4(ndc, 1) * invProj
float3 vs = hcs.xyz / hcs.w

#3 TiagoCosta   Members   

3655
Like
0Likes
Like

Posted 04 May 2012 - 05:06 PM

Thanks I totally forgot to do the w-divide.




Old topic!

Guest, the last post of this topic is over 60 days old and at this point you may not reply in this topic. If you wish to continue this conversation start a new topic.