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OpenGL Appling texture help! NOOB !!

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Hello every boady!!!! im traying to use a texture with opengl under linux. I load it using FreeImage and then convert to apply it. the problem is that the result is not the spected. Here it is!!!! display i don't know what peace off code do you need. I paste what i think is relevant! thanks in advance and sorry!!! ---------------
unsigned char *data = FreeImage_GetBits(bmp);
glTexImage2D(GL_TEXTURE_2D, 0, 3, w,h, 0, GL_RGB, GL_UNSIGNED_BYTE, data);
glutInitDisplayMode (GLUT_RGB);
---------------

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What is the size of your texture? It has to be a multiple of 8/16/or 32. (I recommend 32x32)

Also, it would be helpful to tell us the tex coords as well.

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OK i try 32*32 but still get the same!
here are the coords.

first i try this!


glVertex3f(w / 2,h ,0);glTexCoord2f(w / 2,h);
glVertex3f(w / 2 + w,h,0);glTexCoord2f(w / 2 + w,h);
glVertex3f(w / 2 + w,2*h,0);glTexCoord2f(w / 2 + w,2*h);
glVertex3f(w/ 2 ,2*h,0); glTexCoord2f(w/ 2 ,2*h);



then this!

glVertex3f(0,0,0);glTexCoord2f(0,0);
glVertex3f(w,0,0);glTexCoord2f(w,0);
glVertex3f(w ,h,0);glTexCoord2f(w,h);
glVertex3f(0,h,0); glTexCoord2f(0,h);


but get the same shit!
where

FIBITMAP *bmp = FreeImage_Load (fifmt,FTLoad, 0);
unsigned h=FreeImage_GetHeight(bmp);
unsigned w=FreeImage_GetWidth(bmp);
glOrtho(0.0, 2*GetW(), 0.0,3*GetH(), 0, 1.0);


thank dude!

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Try this:

glVertex3f(0,0,0);glTexCoord2f(0.0f,0.0f);
glVertex3f(w,0,0);glTexCoord2f(1.0f,0.0f);
glVertex3f(w ,h,0);glTexCoord2f(1.0f,1.0f);
glVertex3f(0,h,0); glTexCoord2f(0.0f,1.0f);

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Firstly, every modern graphics card and driver supports textures that aren't powers of 2. They might run slower on some older cards, but they'd be supported.

Okay, for your problem. I suggest using one of the other values (such as GL_RGB8) for the internalformat (third) parameter to glTexImage2D. They are more descriptive and make it more obvious as to what you get. Next, double check what format FreeImage_GetBits() gives you the images in. It could have an Alpha channel. If so, you'd have to use a different value for the format (7th) parameter to glTexImage2D that would fit the actual format (eg: GL_RGBA).

Notice that I'm thinking that the problem is with your call to glTexImage2D. That's because the problem looks to me as if it's got the wrong number of bytes or channels and is, hence, using parts of one pixel for another.

And finally, put in some code to make sure that FreeImage_GetBits() hasn't failed. That's all I can think of, good luck.

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ok1!!!
it's getting beter!!!!
thanks!!!
now i get this

get

but im supossed to get this

want


guess the problem is with rgb, but i can`t figure it out!!!
its twisted and blue!!!

if i want to use a larger texture like 200*300 i cant right?
it should be 200,304?
thx!!!!!

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Quote:
Original post by Ezbez
Firstly, every modern graphics card and driver supports textures that aren't powers of 2. They might run slower on some older cards, but they'd be supported.

i guess this answer one of my quiestion thx!!!!
Quote:
Original post by Ezbez
Okay, for your problem. I suggest using one of the other values (such as GL_RGB8) for the internalformat (third) parameter to glTexImage2D. They are more descriptive and make it more obvious as to what you get. Next, double check what format FreeImage_GetBits() gives you the images in. It could have an Alpha channel. If so, you'd have to use a different value for the format (7th) parameter to glTexImage2D that would fit the actual format (eg: GL_RGBA).

i trye but get the same. i fixit with de coords that crypter sugested!!!

Quote:
Original post by Ezbez
And finally, put in some code to make sure that FreeImage_GetBits() hasn't failed. That's all I can think of, good luck.

i all ready do that and is supossed to work!!!!
thank YOU!!!
now i have the blu problem!!!!
:D

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color Finally fixed!!!!!
here is the code!!!!!

BYTE *bits = new BYTE[FreeImage_GetWidth(bmp) * FreeImage_GetHeight(bmp) * 3];
BYTE *pixels = (BYTE*)FreeImage_GetBits(bmp);

y add those lines!!!!
and now it works!!!!!
but still have the twisted problem thx!!!!!!!
good fights!!! god nights!!!!
thank you all!!!

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OK its all runing!!!!
thank you people!!!! you really help!!!!!!!!!!!!!
i fix the twist by playin with the coords!
final these ones works



glVertex3f(0,0,0);glTexCoord2f(1.0f,0.0f);
glVertex3f(w,0,0);glTexCoord2f(1.0f,1.0f);
glVertex3f(w ,h,0);glTexCoord2f(0.0f,1.0f);
glVertex3f(0,h,0); glTexCoord2f(0.0f,0.0f);

thank you all!!!!!!!!!!!!!!!!!!!!!1

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I know that you fixed your problem. Ive also had the same problem with the colors and i figured it out.
BMP textures are stored in BGR and not RGB. All i had to do was use GL_BGR_EXT when i call glTexImage2D() instead of GL_RGB.

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