Ah, yes thanks for catching that. The function in the tutorial had source as a GLchar**, I have changed it to GLchar* and missed to change that part.
Doesn't seem to be related to my crash error though.
How do I check that my video card supports it? I have a newer card Geforce GTS250 i think it is.
Lighting sparse meshes
glGetString(GL_EXTENSIONS) gives you all supported extensions.
try hardcoding your shader code in the program to see if thats a problem
try hardcoding your shader code in the program to see if thats a problem
Author
O, yea I have looked at that and GLEW has pulled in the proper extensions as far as I can see. I think it would tell me that the function is undefined if that was the problem.
Edit:
I just noticed in the debugger that the vshadesource and fshadesource pointers are still at 0 when I get to glShaderSourceARB so it must be a failure of of the loading function. I'll step through it and see what I can find out.
Edit:
I just noticed in the debugger that the vshadesource and fshadesource pointers are still at 0 when I get to glShaderSourceARB so it must be a failure of of the loading function. I'll step through it and see what I can find out.
Author
Fixed by passing the source pointer by reference. It looks funny though
Compiled successfully. Now I just need to get glDrawElements to work without crashing.
Edit: Ack! forgot to create the shader program :)
Sint32 LoadShader(char* filename_, GLchar*& source_)Compiled successfully. Now I just need to get glDrawElements to work without crashing.
Edit: Ack! forgot to create the shader program :)
Author
It's working now but I'm a little confused because:
Even if my vert shader or frag shader does not compile, or contains and empty main function that does nothing, I still get some drawing.
I set 3 attrib pointers (interleaved), but nowhere do I specify that the first one is the position.
Does OpenGL automatically use the first attribute as a position vertex?
Otherwise I'm a little confused as to how it could know how to render my VBO data.
Even if my vert shader or frag shader does not compile, or contains and empty main function that does nothing, I still get some drawing.
I set 3 attrib pointers (interleaved), but nowhere do I specify that the first one is the position.
Does OpenGL automatically use the first attribute as a position vertex?
Otherwise I'm a little confused as to how it could know how to render my VBO data.
Author
Might this have something to do with it? Quote from http://www.opengl.org/sdk/docs/tutorials/ClockworkCoders/attributes.php
When enable or set an attribute pointer
in this case attribute "0", whenever I use gl_Vertex in my shader source, it is looking at this attribute?
It seems to be so. When I use attribute 8 for the texture coordinate part of my Vertex
I suddenly get texture to display properly!
This shader code is generating an error C5052: gl_MultiTexCoord0 is not accessible in this profile
But at the same time the texture is rendering! I'm really mystified as to how this is possible.
vertshader.vertfragshader.frag
Quote:In other words, NVidia hardware indices are reserved for built-in attributes:
gl_Vertex 0
gl_Normal 2
gl_Color 3
gl_SecondaryColor 4
gl_FogCoord 5
gl_MultiTexCoord0 8
gl_MultiTexCoord1 9
gl_MultiTexCoord2 10
gl_MultiTexCoord3 11
gl_MultiTexCoord4 12
gl_MultiTexCoord5 13
gl_MultiTexCoord6 14
gl_MultiTexCoord7 15
When enable or set an attribute pointer
glEnableVertexAttribArray(0);glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(TexNormVert), 0);in this case attribute "0", whenever I use gl_Vertex in my shader source, it is looking at this attribute?
It seems to be so. When I use attribute 8 for the texture coordinate part of my Vertex
glEnableVertexAttribArray(8);glVertexAttribPointer(8, 2, GL_FLOAT, GL_FALSE, sizeof(TexNormVert), (GLvoid*) (NULL + sizeof (GL_FLOAT) * 6) );I suddenly get texture to display properly!
This shader code is generating an error C5052: gl_MultiTexCoord0 is not accessible in this profile
But at the same time the texture is rendering! I'm really mystified as to how this is possible.
vertshader.vert
void main(){ gl_Position = ftransform();} uniform sampler2D tex;void main(){ gl_FragColor = texture2D(tex, gl_MultiTexCoord0);}
If you will use glVertexAttribPointer, then do not use gl_Vertex in your shader.
NEVER use ftransform().
You must declare attrib in your shader as I show here
http://www.opengl.org/wiki/GlVertexAttribPointer
NEVER use ftransform().
You must declare attrib in your shader as I show here
http://www.opengl.org/wiki/GlVertexAttribPointer
Author
Edit: updated a bit. Still no drawing visible:
Here is setup after shaders are compiled:
Here is building VAO and VBO for each object:Then the drawing step:
And right now the shaders are like so:
Screen is blank, no drawing at all.
[Edited by - PrestoChung on December 12, 2010 8:22:58 AM]
Here is setup after shaders are compiled:
Shader_Program = glCreateProgramObjectARB();glAttachObjectARB(Shader_Program, vshadehandle);glAttachObjectARB(Shader_Program, fshadehandle);glBindAttribLocationARB( Shader_Program, 0, "inVertex" );glBindAttribLocationARB( Shader_Program, 1, "inNormal" );glBindAttribLocationARB( Shader_Program, 2, "inTexCoord0" );glBindFragDataLocation( Shader_Program, 0, "outFragColor" );glLinkProgramARB( Shader_Program );glUseProgramObjectARB( Shader_Program );Here is building VAO and VBO for each object:
glGenVertexArrays(1, &Vao_Handle);glBindVertexArray(Vao_Handle);glGenBuffersARB(1, &Vbo_Handle);glBindBufferARB(GL_ARRAY_BUFFER_ARB, Vbo_Handle);glBufferDataARB(GL_ARRAY_BUFFER_ARB, sizeof(vertices[0])*vertices.size(), &vertices[0], GL_STATIC_DRAW_ARB); glEnableVertexAttribArray(0);glEnableVertexAttribArray(1);glEnableVertexAttribArray(2);glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(TexNormVert), 0);glVertexAttribPointer(1, 3, GL_FLOAT, GL_TRUE, sizeof(TexNormVert), (GLvoid*) (NULL + sizeof (GL_FLOAT) * 3) );glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, sizeof(TexNormVert), (GLvoid*) (NULL + sizeof (GL_FLOAT) * 6) );glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, Vbo_Element_Index);glBindVertexArray(0);glBindVertexArray(Vao_Handle);glDrawElements(GL_TRIANGLES, NumIndices(Portal_Walls.size()), GL_UNSIGNED_BYTE, 0);glBindVertexArray(0);And right now the shaders are like so:
/////////Vertex Shader#version 150uniform mat4 ProjectionModelviewMatrix;in vec4 inVertex;in vec2 inTexCoord0;out vec2 outTexCoord0;void main(){ gl_Position = ProjectionModelviewMatrix * inVertex; outTexCoord0 = inTexCoord0;} /////////////Fragment Shader#version 150uniform sampler2D tex;in vec2 outTexCoord0;out vec4 outFragColor;vec4 mycolor;void main(){ mycolor = texture2D(tex, outTexCoord0); outFragColor = mycolor;} Screen is blank, no drawing at all.
[Edited by - PrestoChung on December 12, 2010 8:22:58 AM]
Author
Quote:Original post by V-man
Why do you use GL_UNSIGNED_BYTE?
Thats the type of my element arrays.
GLubyte indices0[] = { 3, 1, 0, ... };This topic is closed to new replies.
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