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OpenGL need help in multitexturing using opengl shading language (solved)

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Hello! I created this shaders: vertex shader: attribute float texturesin1; attribute float texturesin2; attribute float texturesin3; attribute float texturesin4; varying float texturesout1; varying float texturesout2; varying float texturesout3; varying float texturesout4; void main(void) { gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex; gl_TexCoord[0] = gl_MultiTexCoord0; gl_TexCoord[1] = gl_MultiTexCoord1; gl_TexCoord[2] = gl_MultiTexCoord2; gl_TexCoord[3] = gl_MultiTexCoord3; texturesout1 = texturesin1; texturesout2 = texturesin2; texturesout3 = texturesin3; texturesout4 = texturesin4; } fragment shader: uniform sampler2D deeptexture; uniform sampler2D lowtexture; uniform sampler2D hightexture; uniform sampler2D toptexture; varying float texturesout1; varying float texturesout2; varying float texturesout3; varying float texturesout4; void main (void) { vec4 deep = texture2D(deeptexture, gl_TexCoord[0].st ); vec4 low = texture2D(lowtexture, gl_TexCoord[1].st ); vec4 high = texture2D(hightexture, gl_TexCoord[2].st ); vec4 top = texture2D(toptexture, gl_TexCoord[3].st ); vec4 newcolor = texturesout1 * deep + texturesout2 * low + texturesout3 * high + texturesout4 * top; gl_FragColor = newcolor; } This shader helps me to draw a terrain with 4 textures depending on high. I compute the texture combination values, and I pass it to the vertex shader. THe values are stored in a vertex buffer object. My problem is, that if I pass the textureout values through the vertex shader, and I want to use it in the framgent shader, it is extremely slow (0.1fps). When I use a constant value in the framgent shader, it is running with 400fps. How can I fix this problem? thanks. [Edited by - fazekaim on January 2, 2005 7:53:14 AM]

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sounds like its dumpped out to software, check the compiler logs to see if it says anything.

btw, in your vertex shader you are better off doing gl_Position = ftransform();

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When the compiler fails, I write the compiler error message.
The shaders are compiled successfull.
Is there any other compiler output?

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should work what card do u have?

instead of passing it as 4 attribute floats try a single vec4 eg gl_MultiTexCoord5 or color

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You have write. I received this warning:
The GLSL vertex shader will run in software - number of hardware supported vertex attributes exceeded.

I have Radeon 9600XT with 256MByte ram.

How many attributes can I have with this card?

thanks.

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www.google.com knows, but anyways, you know, you could just as easily specify for texture stage 4, a 4 component tex coord, and just inside your vertex shader, treat it like its your texturesinN floats,

now for my own question, what does an attribute do in glsl? i had always thought of attributes as a generic way of looking at normal, position, color ect. but seeing normal vertex properties (position, tex coord, ect) AND attributes, has me a bit confused, anyone care to explain?

thanks
-Dan

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Ademan555 :
an attribute is just a generic way of setting per vertex infomation, they can either be your own or standard GL per vertex values (such as normals).


fazekaim :
You can find the max attributes by using glGet with the token GL_MAX_VERTEX_ATTRIBS_ARB, however you are garented 16 apprently.

However, each one is a vec4, so by using 4 floats you've used 4 vec4s up

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hrm, thats what i thought, so how would you set the attributes then for his shader? because wouldnt attribute0 be position? and such? so youd have to know which attribute his floats were being assigned to.

oh and by the way OP, this is a long shot, but you could try making it just one vec4 also... if openGL tags on the attributes to whatever open attrib is available, it may do it one by one and thus waste 3 attribs by using each float as an attribute rather than packing them (though i think youd still be under the limit)

hope that helps
-Dan

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I'm confused too. I received this value:
GL_MAX_VERTEX_UNIFORM_COMPONENTS_ARB:4096
GL_MAX_VARYING_FLOATS_ARB:44
GL_MAX_VERTEX_ATTRIBS_ARB:32

I excedeed the 32 attributes? How?

How can I add values from a VBO to an uniform variable?

I know how to implement using attribute, but using uniform variable? It is possible?

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Quote:
Original post by Ademan555
hrm, thats what i thought, so how would you set the attributes then for his shader? because wouldnt attribute0 be position? and such? so youd have to know which attribute his floats were being assigned to.


You ask OGL where a certain attribute is via the GLSL C API, I'm pretty sure that you can also tell OGL what attribute to put into what position pre-linking.

So, in this case you'd ask where "texturesin1" is and then assign a value to that location

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Quote:
Original post by fazekaim
GL_MAX_VERTEX_ATTRIBS_ARB:32
I excedeed the 32 attributes? How?


What vertex streams do you have active?
As you've used 9 that I can see (the 4 texturesin, the 4 texture coords and the gl_Vertex) just from that shader, however given that you've got 32 I'd be impressed if you've run out, it might be a driver bug, in which case contacting someone at ATI might be a plan...

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Well, seeing those kindw of numbers for a 9600 makes me want to migrate to glsl :-D, sooo..... i gotta ask, this is the extension for glsl functionality right? http://oss.sgi.com/projects/ogl-sample/registry/ARB/shader_objects.txt

edit: UGH, so many new functions... is there a way to create a static lib for an existing dll? its about time someone made a lib for it and made glext into a bunch of import functions (wrong term probably) ie: extern "C" { FUNCS };

thanks
-Dan

[Edited by - Ademan555 on January 1, 2005 6:07:45 PM]

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Quote:
What vertex streams do you have active?
As you've used 9 that I can see (the 4 texturesin, the 4 texture coords and the gl_Vertex) just from that shader, however given that you've got 32 I'd be impressed if you've run out, it might be a driver bug, in which case contacting someone at ATI might be a plan...


im not 100% sure but if its anythjing like varying its the number of components that counts
eg 1 texture coord prolly counts as 4
(this caught me out before with varying stuff)

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Quote:
Original post by Ademan555
edit: UGH, so many new functions... is there a way to create a static lib for an existing dll? its about time someone made a lib for it and made glext into a bunch of import functions (wrong term probably) ie: extern "C" { FUNCS };


Thats what stuff like GLee is for, check the forum FAQ.

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Quote:
Original post by zedzeek
im not 100% sure but if its anythjing like varying its the number of components that counts
eg 1 texture coord prolly counts as 4
(this caught me out before with varying stuff)


I did consider that, but given how the Orange book shows things lineing up that doesnt make sense, as it has gl_Vertex as one attribute for example, which is 4 floats.

However, given his problems and your point about varying it could well be the issue as 9*4 gives 36floats used up, above the limit which would explain the error

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>>I did consider that, but given how the Orange book shows things lineing up that doesnt make sense, as it has gl_Vertex as one attribute for example, which is 4 floats.<<

i looked at the gl spec last night, and im now pretty sure u were correct, ie the size of each attribute is not important (unlike the varying variables) also it states an app must support at least 16attributes

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didnt think i was going crazy [wink]
Which doesnt explain why it doesnt work as he's only use up 9 attributes o.O
Maybe I'll remember to ask ATI devrel about it at some point...

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