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Icarus0508

OpenGL a question about geometry shader and FBO

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Icarus0508    122
Hi i am new in opengl. i tried to render 6 textures simultaneously by tex_array and Geometry shader. how can i get the texture from a texture_array after rendering to the targets? glGetTexImage(GL_TEXTURE_2D_ARRAY_EXT, 0, GL_RGBA, GL_UNSIGNED_BYTE, gVisibilityTexturePixels); does not work since it can not control the layers of texture_array. Can someone help me? thank you

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bubu LV    1436
Accordingly to spec GetTexImage returns all layers of array texture:
Quote:
(14) Should we provide a way to query a single layer of an array texture?

RESOLVED: No; we don't expect this to be an issue in practice.
GetTexImage() will return a two- or three-dimensional image for one- and
two-dimensional arrays, including all levels. If this were identified
as an important need, a follow-on extension could be added in the
future.

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Icarus0508    122
Thanks for answer.

i followed spec but it still nothing.

i think the bug is at the setting of FBO

here is some codes:
creating:
glEnable(GL_TEXTURE_2D_ARRAY_EXT);
glEnable(GL_TEXTURE_3D_EXT);
glEnable( GL_FRAMEBUFFER_EXT );

glGenTextures(1, &tColorCubeMap);
glBindTexture(GL_TEXTURE_2D_ARRAY_EXT, tColorCubeMap);
.......
glTexImage3DEXT(GL_TEXTURE_2D_ARRAY_EXT, 0, GL_RGBA, 1024, 1024, 6, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);

glGenTextures(1, &tDepthCubeMap);
glBindTexture(GL_TEXTURE_2D_ARRAY_EXT, tDepthCubeMap);
.......
glTexImage3DEXT(GL_TEXTURE_2D_ARRAY_EXT, 0, GL_DEPTH_COMPONENT24, 1024, 1024, 6, 0, GL_RGB, GL_FLOAT, NULL);

glGenFramebuffersEXT(1, &fbo);
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo);
glDrawBuffer(GL_NONE);

glFramebufferTextureEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, tDepthCubeMap, 0 );
glFramebufferTextureEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, tColorCubeMap,0);


rendering:

glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo);
for (int i=0;i<6;i++)
{
glFramebufferTextureLayerEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, tDepthCubeMap, 0 ,i);
glFramebufferTextureLayerEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, tColorCubeMap,0,i);
glClear(GL_COLOR_BUFFER_BIT |GL_DEPTH_BUFFER_BIT);

RenderScene();

}
tDepthCubeMap and tColorCubeMap are Texture_array.
and i used GS to render through gl_layers.
VS:
void main()
{
gl_Position = ftransform();
}
GS:
void main()
{


int i, layer;
for (layer = 0; layer < 6; layer++)
{
gl_Layer = layer;
for (i = 0; i < 3; i++)
{

gl_Position = gl_PositionIn[i];


EmitVertex();
}
EndPrimitive();
}

}
PS:
void main (void)
{

gl_FragData[0] = vec4(0.0,0.0,1.0,1.0);

}

Is the setting wrong?

thanks

[Edited by - Icarus0508 on May 5, 2009 12:32:58 AM]

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