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Array Pointers

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Hairu    122
Has anyone successfully got "index" vertex arrays to work with texture arrays? If so, does the index pointer work for both the texture array and the vertex array, or just the vertex array? What i''m saying is, should the texture coords also be index in accordance with the vertex array?

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Hairu    122
No, i mean like using the index for the actual vertices of the triangles that I am drawing. Here''s a code sample for a routine in my game library....

void DH_Model::show()
// if we dont have a model, we cant show anything
if(!model_loaded){ DH_Error.push("Model Not Loaded"); return; }

// if a texture box is set, use it to set the texture

// set the texture coordinate arrays
glTexCoordPointer(2, GL_FLOAT, 0, TexCoords);

// set the normal arrays
glNormalPointer(GL_FLOAT, 0, Normals);

// set the vertex pointer
glVertexPointer(3, GL_FLOAT, 0, Vert_public);

// show the model
glDrawElements(GL_TRIANGLES, header.numFaces*3, GL_UNSIGNED_INT, index);


The problem is, i''m not sure how i should setup my texture array "TexCoords". The results i''m getting, are different than I expected. I''m building the array as if it wasn''t indexed. Is this correct?

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zedzeek    528

u should have exactlly the same number of vertices as texcoords as normals

eg for a square u have

| |
| |
A-----D 4 verts, 4 texcoords, 4 normals
verts[] = { {0,0,0}, {0,1,0}, {1,1,0}, {1,0,0} };
texcoords[] { { 0,0 }, { 0,1 }, { 1,1 }, { 1,0 } };
normals[] = { {0,0,1}, {0,0,1}, {0,0,1}, {0,0,1} };

GLuint index[] = {0,1,2,3};
glDrawElements( GL_QUADS, 4, GL_UNSIGNED_INT, index );

or in this case better(faster) yet

glDrawArrays( GL_QUADS, 0, 4 );

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