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[Obunako]

Hello, i try to use Vertex Arrays With Multitexture extension, but don't work it. :(

my source code...

Start up function ( Only once, at the begin of my app )

//Load TextureFile1 ( some code )

glGenTextures(1,&ntexture[0]);
glActiveTextureARB (GL_TEXTURE0_ARB);
glBindTexture(GL_TEXTURE_2D, ntexture[0]);
glEnable (GL_TEXTURE_2D);
glTexImage2D(GL_TEXTURE_2D, 0,3, 256, 256, 0,GL_BGR_EXT, GL_UNSIGNED_BYTE,sprite);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S, GL_CLAMP);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T, GL_CLAMP);


I repeat this code for texturefile2 changing ...TEXTURE0... by ...TEXTURE1... and ntexture[0] by ntexture[1].

( this parts seems ok, because in non multitexture mode, no problems produce )

glEnable (GL_TEXTURE_2D);
glEnableClientState (GL_VERTEX_ARRAY);
glEnableClientState (GL_TEXTURE_COORD_ARRAY);




RenderFunction

glActiveTextureARB (GL_TEXTURE0_ARB);
glClientActiveTextureARB (GL_TEXTURE0_ARB);
glTexCoordPointer (2,GL_FLOAT,0,na);
glVertexPointer (3,GL_FLOAT,0,va);

glActiveTextureARB (GL_TEXTURE1_ARB);
glClientActiveTextureARB (GL_TEXTURE1_ARB);
glTexCoordPointer (2,GL_FLOAT,0,na);

glDrawElements(GL_TRIANGLE_STRIP, 4, GL_UNSIGNED_INT, indices );


glActiveTextureARB (GL_TEXTURE0_ARB);
glClientActiveTextureARB (GL_TEXTURE0_ARB);
glTexCoordPointer (2,GL_FLOAT,0,na);
glVertexPointer (3,GL_FLOAT,0,va);

glActiveTextureARB (GL_TEXTURE1_ARB);
glClientActiveTextureARB (GL_TEXTURE1_ARB);
glTexCoordPointer (2,GL_FLOAT,0,na);


glDrawElements(GL_TRIANGLE_STRIP, 4, GL_UNSIGNED_INT, indices );

... ;-( ;-( i render all balck ;-( ;-(


I don't understand the diferences between alActive... and glClientActive... functions. May be this is the problem of my render function.

Thanks All.

[olawlor]

You've probably figured this out, but for future reference you just need to make the "EnableClientState" call *after* activating the appropriate client texture unit, like so:

glEnableClientState(GL_VERTEX_ARRAY);
glVertexPointer(3,GL_FLOAT,...); /* position */

glClientActiveTextureARB (GL_TEXTURE1_ARB);
glEnableClientState (GL_TEXTURE_COORD_ARRAY);
glTexCoordPointer(4,GL_FLOAT,...); /* texcoord1 */

glClientActiveTextureARB (GL_TEXTURE0_ARB);
glEnableClientState (GL_TEXTURE_COORD_ARRAY);
glTexCoordPointer(3,GL_FLOAT,...); /* texcoord0 */

The trouble here is that glEnableClientState applies to the *current* texture unit, like most of the texture state, so you've got to turn it on for *each* unit. The same thing works for vertex arrays as well as vertex buffer objects.

Be sure to glActiveTextureARB and glEnable(GL_TEXTURE_2D) for each unit before rendering too!