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OpenGL FadeOut effect/semi transparency

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I am trying to obtain a simple fadeout effect by having a big textured quad cover the screen with the alpha that gradually increases until being full black... I don't quite understand in what part of the drawing code I should alter the alpha...... I have a wrapper class for textures, this is how I load a texture:

void GLTexture::LoadBMP(char *name)
// Create a place to store the texture
AUX_RGBImageRec *TextureImage[1];

// Set the pointer to NULL
memset(TextureImage,0,sizeof(void *)*1);

// Load the bitmap and assign our pointer to it
TextureImage[0] = auxDIBImageLoad(name);

// Just in case we want to use the width and height later
width = TextureImage[0]->sizeX;
height = TextureImage[0]->sizeY;

// Generate the OpenGL texture id
glGenTextures(1, &texture[0]);

// Bind this texture to its id
glBindTexture(GL_TEXTURE_2D, texture[0]);

// Use mipmapping filter

// Generate the mipmaps
gluBuild2DMipmaps(GL_TEXTURE_2D, 3, TextureImage[0]->sizeX, TextureImage[0]->sizeY, GL_RGB, GL_UNSIGNED_BYTE, TextureImage[0]->data);

// Cleanup
if (TextureImage[0])
if (TextureImage[0]->data)


Then in the drawing section I enable glBlend and activate the texture:


glMatrixMode (GL_MODELVIEW);

glClearColor( 1.0f, 1.0f, 1.0f, 1.0f );

glEnable( GL_BLEND );

//Draw the textured quad here

void GLTexture::Use()
glEnable(GL_TEXTURE_2D); // Enable texture mapping
glBindTexture(GL_TEXTURE_2D, texture[0]); // Bind the texture as the current one


Is there somewhere in this structure that I can implement said effect?

Thanks for your help

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thanks, I have tried that but I don't really notice any transparency, even when setting it to 0!

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Have you done anything with glTexEn()? glColor4f() called before drawing will work. Does glColor4f(1,0,0,1) turn your texture red?

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