mixing vbo and vertexattribarrays
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is there anyway you can mix using vbos and vertex attribute arrays? It doesn't work, should it, or is it a driver bug?
Quote:Original post by GrumpyAndTired
is there anyway you can mix using vbos and vertex attribute arrays? It doesn't work, should it, or is it a driver bug?
I think it should (i'm doing this all the time).
Because glVertexAttribPointerARB define a generic vertex attribute, i think you must use a vertex program with it. Given that glVertexAttribPointerARB (and the others) are introduced by GL_ARB_vertex_program, this seems a logical explanation. I think i've read this somewhere i don't remember where (and i can't find it now).
Have you tried them with a vp?
HellRaiZer
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yes, well I am using VBO for my geometry, and doing bump mapping with shaders. However, when I use a VBO, my tangent vertex array doesn't upload. If I turn off using VBOs, it works fine. I am not sure why.
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void geom_BuildVBO( GLGeometry * pG, bool mode){ GLenum flags; if(mode) flags = GL_STATIC_DRAW_ARB; else flags = GL_DYNAMIC_DRAW_ARB; if(!GLEW_ARB_vertex_buffer_object) return; gpu_GenBuffers(1,&pG->vbxyz); gpu_BindBuffer(GL_ARRAY_BUFFER_ARB,pG->vbxyz); gpu_BufferData(GL_ARRAY_BUFFER_ARB,(pG->numverts*4)*sizeof(jreal_t),pG->xyz,flags); if(pG->normals) { gpu_GenBuffers(1,&pG->vbnormals); gpu_BindBuffer(GL_ARRAY_BUFFER_ARB,pG->vbnormals); gpu_BufferData(GL_ARRAY_BUFFER_ARB,(pG->numverts*4)*sizeof(jreal_t),pG->normals,flags); } if(pG->color) { gpu_GenBuffers(1,&pG->vbcolor); gpu_BindBuffer(GL_ARRAY_BUFFER_ARB,pG->vbcolor); gpu_BufferData(GL_ARRAY_BUFFER_ARB,(pG->numverts*4)*sizeof(jcolortype_t),pG->color,flags); } if(pG->bcolor) { gpu_GenBuffers(1,&pG->vbbcolor); gpu_BindBuffer(GL_ARRAY_BUFFER_ARB,pG->vbbcolor); gpu_BufferData(GL_ARRAY_BUFFER_ARB,(pG->numverts*4)*sizeof(jcolortype_t),pG->bcolor,flags); } for(int i = 0; i < pG->numtexsets; i++) { if( pG->st ) { gpu_GenBuffers(1,&pG->vbst); gpu_BindBuffer(GL_ARRAY_BUFFER_ARB,pG->vbst); gpu_BufferData(GL_ARRAY_BUFFER_ARB,(pG->numverts*2)*sizeof(jreal_t),pG->st,flags); } } if( pG->index ) { gpu_GenBuffers(1,&pG->vbindex); gpu_BindBuffer(GL_ELEMENT_ARRAY_BUFFER_ARB,pG->vbindex); gpu_BufferData(GL_ELEMENT_ARRAY_BUFFER_ARB,(pG->numindices)*sizeof(jushort),pG->index,flags); } if( pG->p_packed ) { for( int i = 0; i < pG->num_packed; i++) { gpu_GenBuffers(1,&pG->p_packed.vbindex); gpu_BindBuffer(GL_ELEMENT_ARRAY_BUFFER_ARB,pG->p_packed.vbindex); gpu_BufferData(GL_ELEMENT_ARRAY_BUFFER_ARB,(pG->p_packed.numindices)*sizeof(jushort),pG->p_packed.index,flags); } } gpu_BindBuffer(GL_ELEMENT_ARRAY_BUFFER_ARB,0); gpu_BindBuffer(GL_ARRAY_BUFFER_ARB,0); }This is how I initialize the VBOs.
I think you need to put all this data into single VBO, since you can have only 1 vbo binded per draw call.
So figure out the size of the buffer based on what attributes you need, like
p.s. why aren't plus signs showing up?
So figure out the size of the buffer based on what attributes you need, like
buffer_size = numverts * sizeof(vertex);if ( normals ) buffer_size += numverts*sizeof(normal);if ( colors ) buffer_size += numverts*sizeof(color);if ( texcoords ) buffer_size += numverts*sizeof(texcoord);char *data = new char[buffer_size];ofs = 0;memcpy ( data, verts, numverts*sizeof(vertex));ofs += numverts*sizeof(vertex);if( normals ) { memcpy ( data + ofs, normals, numverts*sizeof(normal)); ofs += numverts*sizeof(normal);}if( colors ) { ...}etc..glGenBuffers(1, &vbo );glBindBuffer(GL_ARRAY_BUFFER_ARB,vbo);glBufferData(GL_ARRAY_BUFFER_ARB,buffer_size,data,flags);free[] data;p.s. why aren't plus signs showing up?
Author
I just got it to work. I was binding the vertex attrib array after the VBO stuff, and I think it messed it up for some reason.
christian h: you can bind as much vbos as you like (from performance view this isnt really efficient but theoretically...)
Quote:Original post by Eitsch
christian h: you can bind as much vbos as you like (from performance view this isnt really efficient but theoretically...)
Really? I never figured that out. So does it work like this:
BindBuffer(..)VertexPointer(..)BindBuffer( another buffer )NormalPointer(..)BindBuffer( yet another buffer )..DrawElements(..)This topic is closed to new replies.
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