Forums - Adreno 205 Displaying garbage

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Adreno 205 Displaying garbage
Join Date: 13 Jan 12
Posts: 1
Posted: Fri, 2012-01-13 10:56

I'm working on an OpenGL ES plugin for a playstation emulator, and the plugin works fine on other chipsets, but the Adreno205 causes it to display garbage in the pillarbox margins when running in 4:3 landscape mode.

glClear() is called between frames, with glClearColor(0,0,0,128) set, and these are called after a disable and before a re-enable of GL_SCISSOR_TEST (used to display the screen in 4:3 size).

Has anyone run into a similar problem before, where they're attempting to pillarbox 4:3 content on the Adreno 205 and getting garbage data instead of black in the pillarboxing?  Thanks!

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Mark_Feldman Moderator
Join Date: 4 Jan 12
Posts: 61
Posted: Wed, 2012-02-22 16:13

Could you share a bit more information on the sequence and parameters of your gl calls (glclear, glenable, gldisable, glScissor, etc)?

Pseudo code would be helpful as well.


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Join Date: 12 Oct 12
Posts: 3
Posted: Wed, 2012-10-17 18:26

Just finished hunting down bug in our code that is somewhat related to the topic at hand. It seems -- if rendering in a viewport smaller than the screen buffer (so as to letterbox 4:3 graphics) both color buffer and depth buffer (and possibly others?) contain garbage in the 'black bar' region, unless glClear is called every frame. PowerVR SGX540 and NVidia Tegra2 do not have this issue and keep the  'black bar' region faithfully blank.

I was just wondering if someone from the Adreno team could chime in...

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