iPhone OpenGL texture not completely transparent - iphone

Question

I tried to paint a transparent texture over a sphere, but the transparent areas are not completely transparent. A vivid shade of gray remains. I tried to load a Photoshop generated PNG then paint it on sphere using the code below:
My code to load textures:
- (void) loadPNGTexture: (int)index Name: (NSString*) name{
CGImageRef imageRef = [UIImage imageNamed:[NSString stringWithFormat:#"%#.png",name]].CGImage;
GLsizei width = CGImageGetWidth(imageRef);
GLsizei height = CGImageGetHeight(imageRef);
GLubyte * data = malloc(width * 4 * height);
if (!data)
NSLog(#"error allocating memory for texture loading!");
else {
NSLog(#"Memory allocated for %#", name);
}
NSLog(#"Width : %d, Height :%d",width,height);
CGContextRef cg_context = CGBitmapContextCreate(data, width, height, 8, 4 * width, CGImageGetColorSpace(imageRef), kCGImageAlphaPremultipliedLast);//kCGImageAlphaPremultipliedLast);
CGContextTranslateCTM(cg_context, 0, height);
CGContextScaleCTM(cg_context, 1, -1);
CGContextDrawImage(cg_context, CGRectMake(0, 0, width, height), imageRef);
CGContextRelease(cg_context);
CGContextSetBlendMode(cg_context, kCGBlendModeCopy); //kCGBlendModeCopy);
glGenTextures(2, m_texture[index]);
glBindTexture(GL_TEXTURE_2D, m_texture[index][0]);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
free(data);
}
Drawing clouds:
glPushMatrix();
glTranslatef(0, 0, 3 );
glScalef(3.1, 3.1, 3.1);
glRotatef(-1, 0, 0, 1);
glRotatef(90, -1, 0, 0);
glDisable(GL_LIGHTING);
//Load Texture for left side of globe
glBindTexture(GL_TEXTURE_2D, m_texture[CLOUD_TEXTURE][0]);
glVertexPointer(3, GL_FLOAT, sizeof(TexturedVertexData3D), &VertexData[0].vertex);
glNormalPointer(GL_FLOAT, sizeof(TexturedVertexData3D), &VertexData[0].normal);
glTexCoordPointer(2, GL_FLOAT, sizeof(TexturedVertexData3D), &VertexData[0].texCoord);
// draw the sphere
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_COPY);
glDrawArrays(GL_TRIANGLES, 0, 11520);
glEnable(GL_LIGHTING);
glPopMatrix();

Answer 1

This first thing that stands out in your code is the line:
glBlendFunc(GL_SRC_ALPHA, GL_COPY);
The second argument (GL_COPY), is not a valid argument for glBlendFunc.
You might want to change that to something along the lines of
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);