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Manuel C
09-30-2003, 01:19 AM
Hi,

I'm trying to update a texture with glCopyTexSubImage2D() but I get a strange effect...

this is my original texture:
< bug1.gif (http://gemac80.interfree.it/fuffa/bug1.gif) >

this is what I get :
< bug2.gif (http://gemac80.interfree.it/fuffa/bug2.gif) >

I'm using a RGBA8 texture. I checked alpha_bits ( = 8 ).

Here's my code (my window size is 800x600):



glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0,800,0,600,-1.0f,1.0f);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();

glDisable(GL_BLEND);
glColorMask(1,1,1,1);
glColor4f(1,1,1,1);
glBindTexture(GL_TEXTURE_2D,tex);
glBegin(GL_QUADS);
glTexCoord2f(0,1);glVertex2f(0,256);
glTexCoord2f(0,0);glVertex2f(0,0);
glTexCoord2f(1,0);glVertex2f(256,0);
glTexCoord2f(1,1);glVertex2f(256,256);
glEnd();
glBindTexture(GL_TEXTURE_2D,tex);
glCopyTexSubImage2D(GL_TEXTURE_2D,0,0,0,40,40,256, 256);


Thanks...

Manuel

Manuel C
09-30-2003, 01:21 AM
sorry, I mean:




glCopyTexSubImage2D(GL_TEXTURE_2D,0,0,0,0,0,256,25 6);

Mazy
09-30-2003, 01:42 AM
I dont see the creatation of the texture.. it seems like the texture isnt 256 pixels wide.. only 32 or so ( the effect comes from bilienar filter)

Manuel C
09-30-2003, 05:05 AM
Originally posted by Mazy:
I dont see the creatation of the texture.. it seems like the texture isnt 256 pixels wide.. only 32 or so ( the effect comes from bilienar filter)

I'm sure texture is 256x256... and I checked with glGet(witdh,height,components)...

Manuel