possible bug found: rendering to texture

[dehseth]

hi guys,
in my application, if I use SetRenderTarget function and render scene to a custom texture I get a nice colorful visual render If I render it to screen directly I do not get the same render...

I figured out if I draw my texture image without using alpha channel I get this same bad render:

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/* same as directly rendering to back buffer */
driver->draw2DImage(texture, rect1, rect2, 0, 0, false);

If I use alpha channel of texture I got a nice render:

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/* different than directly rendering to back buffer */
driver->draw2DImage(texture, rect1, rect2, 0, 0, TRUE);

So how can I get the same result when rendering to backbuffer directly? thank you all....


I see no comment on this topic... So no idea ppl?

[greenya]

Maybe post two screenshots with the result renderings, so we will see the differece and the meaning of "nice colorful visual render".

[dehseth]

here's the render I got when I use backbuffer directly:



and this is the nice texture rendering I got:

[dehseth]

is this might be the problem:
present.BackBufferFormat = D3DFMT_X8R8G8B8

any idea?

[dehseth]

well everything has changed suddenly when I realized my shader takes alpha channel variable as last value... and now I have a problem with texture target.. I would like to have my texture without alpha blending...
The problem is when I set

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      driver->setRenderTarget(texture);


I got alpha blended render.. And When I render to backbuffer directly I do not get any alpha blending cause I set

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SIrrlichtCreationParameters

to

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false

so how can I turn off alha blending on rendering to texture target?

and this is how I render the render target texture to backbuffer:

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driver->draw2DImage(texture, rect, recti(vector2di(0,0), dimension), 0,0,false);

[dehseth]

OK I think the problem is when I am rendering to texture the depth buffer is not working and if I render the closer element to cam after others everything's fine, but if I render the closer element before further elements than it overrides pixels..

But If I render the same scene using backbuffer everything is fine!
SO I guess we have a possible bug in here...

[hybrid]

Could you please post the full code of a minimal example reproducing this problem? Also with some image I have access to, in order to check the difference here as well.

[dehseth]

ok I will prepare a small app. and post source code link here when it's ready..

[dehseth]

FINALLY!!! I found THE BUG!

If you create your device (directx 9 device) using antialiasing

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SIrrlichtCreationParameters cp;   
   cp.AntiAlias = 2; // can be some other value


and use a render texture target... than device fails on computing z-buffer (it draws every single mesh to texture over and over in given order)... It does not fail on rendering to backbuffer.. If I close anti-aliasing mode, device succeeds on rendering both texture and backbuffer.

I uploaded small code here:

http://jump.fm/AEPRN

you can easily see rendering to backbuffer does not have any problem and rendering to texture has and z-buffer problem. And please remove anti-aliasing in main function and see texture rendering is fine...

[hybrid]

Ah yeah. That's a problem which occurs on some configurations, probably due to a wrongly chosen, unsupported render texture format. Unfortunately it never happens on my machines, so it's not fixable by me. It would help to create an example which reproduces this problem, and hope for someone to have such a configuration and can debug the dx driver.