Bug 33762

Summary:	Framebuffer Depth textures (Shadow mapping) - FBO-EXT
Product:	Mesa	Reporter:	s3734770
Component:	Drivers/Gallium/r600	Assignee:	Default DRI bug account <dri-devel>
Status:	RESOLVED FIXED	QA Contact:
Severity:	normal
Priority:	medium
Version:	git
Hardware:	x86-64 (AMD64)
OS:	Linux (All)
Whiteboard:
i915 platform:		i915 features:
Attachments:	shadow map Patch that fixes the depth map copying (but not the freeze)

Description s3734770 2011-01-31 07:37:55 UTC

I'm running a depth map demo that uses fbo depth maps as a render target. The fbo (EXT) is filled with static stuff (like a mask that is moved over the screen). So the contents i drawed into the buffer (the depth component is bound to the buffer) are ignored

I don't know if this feature is in progress or if you know what is missing in the driver.
If you have no clue, I can offer the following things after a request:
 - Pics of the artifacts
 - Videos that show that the depth texture is not updated
 - Explanation how i set up the FBO/Renderbuffer

The thing works with fglrx.

Extensions I used:
Framebuffer_EXT
Renderbuffer_EXT (for depth store)

Comment 1 s3734770 2011-01-31 07:40:14 UTC

Here the code:

  glGenFramebuffersEXT(1, @fb);
  glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fb);
  glGenRenderbuffersEXT(1, @render_buf);
  glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, render_buf);
  glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT, ShadowSize, ShadowSize);
  glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, render_buf);

Comment 2 Alex Deucher 2011-01-31 07:47:56 UTC

You'll probably have more luck with the r600 gallium driver (r600g).

Comment 3 s3734770 2011-01-31 08:38:58 UTC

Oh I forgot: Driver is of course r600g.

Comment 4 s3734770 2011-01-31 09:41:12 UTC

i found a demo that reproduces the bug for me:

http://cgit.freedesktop.org/mesa/demos/
in /demos/shadowtex

in all programs the texture looks the same. i attached a pic how the demo looks like. watch the shadow

Comment 5 s3734770 2011-01-31 09:42:17 UTC

Created attachment 42761 [details]
shadow map

Comment 6 s3734770 2011-01-31 12:04:55 UTC

The following hint is given in the docs:

6.3 CB
6.3.1 DB->CB Copies: RV6xx
In RV610, RV630, RV620, and RV635 but not R600, RV670, or RS780, the DB->CB copies needs the following
programming sequence to ensure the DB will read the Z/Stencil data.
1. Z_ENABLE = true
2. STENCIL_ENABLE = true
3. Z_WRITE_ENABLE = false
4. STENCILWRITEMASK = 0xff
5. Z vertices = 0.0. (like a Z clear to 0.0)
6. ZFUNC= LEQUAL
7. STENCILFUNC = REF_ALWAYS
8. STENCILZPASS = STENCIL_KEEP
9. STENCILZFAIL = STENCIL_INCR_CLAMP
10. DB_RENDER_OVERRIDE.FORCE_HIZ_ENABLE = FORCE_DISABLE

It seems to be a RV6xx specific problem. I hope, you can fix it.

Comment 7 Henri Verbeet 2011-01-31 16:25:18 UTC

Probably fixed by d171ae086bae37279251a1d6f32e16e333cfc154, shadowtex is at least.

Comment 8 s3734770 2011-01-31 23:45:44 UTC

the latest changes (between 11bc8991e94e2fa6d461193a6aff47f8f94b7a47 and 5e19b5ad16b2761fe9d8877318f2fc97b229335c) broke the driver.
I can use 2D menus with OGL and glxgears works but when I start using the 3D part (uses FBO, shaders and vertex buffers), the image freezes and I cannot stop my prog.

Comment 9 Dave Airlie 2011-02-01 00:05:36 UTC

does reverting 

11bc8991e94e2fa6d461193a6aff47f8f94b7a47

 fix it?

Comment 10 s3734770 2011-02-01 00:15:31 UTC

Git bisect blamed 14880a510a1a288df0778395097d5a52806abfb0, 
there are strange things happening.
The framerate drops downto 3 FPS and the texture bug appears again.

I also created a patch inspired from glisse that fixes the bug (but is maybe not the correct solution because the tiling management is still unfinished)

Comment 11 s3734770 2011-02-01 00:16:03 UTC

(In reply to comment #9)
> does reverting 
> 
> 11bc8991e94e2fa6d461193a6aff47f8f94b7a47
> 
>  fix it?

no

Comment 12 s3734770 2011-02-01 00:19:08 UTC

Created attachment 42797 [details] [review]
Patch that fixes the depth map copying (but not the freeze)

This patch is inspired by Jerome Glisse
This patch does not solve the problem that the screen is freezing

Comment 13 s3734770 2011-02-01 00:23:53 UTC

When I revert 14880a510a1a288df0778395097d5a52806abfb0, i can play with working depth textures and 3 FPS.

Comment 14 s3734770 2011-02-01 00:26:09 UTC

Ah,
as I see the original problem is fixed in git but the glsl compiler had a deadlock so that I cannot test it.

Comment 15 s3734770 2011-04-07 01:20:28 UTC

resolved long time ago

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