Rendering to a region of a texture

Graphics and GPU Programming Programming

Started by RobM November 07, 2015 10:58 AM

3 comments, last by Tom Sloper 8 years, 5 months ago

1,161

Author

November 07, 2015 10:58 AM

Is it possible to do this in direct X 9? I'm rendering to a very large texture but I only want to update a relatively small region of it. Seems wasteful to render the whole thing?

Hodgman

52,717

November 07, 2015 11:04 AM

Yes, that's what the Viewport state does.

. 22 Racing Series .

RobM

1,161

Author

November 07, 2015 11:32 AM

Yes, that's what the Viewport state does.

Thanks, I did some googling but couldn't find anything obvious - I was wrongly looking for locking

unbird

8,359

November 07, 2015 12:04 PM

Just for completeness here some alternatives:

- Scissors (SetScissorRect)
- If you can define the shape easily with primitives, just render that (e.g. a quad to a certain part of your RT)
- Custom clip planes (SetClipPlane)
- clip/discard in the pixel shader (for more complex shapes)
- use the stencil buffer as a mask