How do I get the correct values from glReadPixels in OpenGL 3.0?
- by NoobScratcher
I'm currently trying to Implement mouse selection into my game editor and I ran into a little problem when I look at the values stored in &pixel[0],&pixel[1],&pixel[2],&pixel[3]; I get
r: 0
g: 0
b: 0
a: 0
As you can see I'm not able to get the correct values from glReadPixels();
My 3D models are red colored using glColor3f(255,0,0);
I was hoping someone could help me figure this out.
Here is the source code:
case WM_LBUTTONDOWN:
{
GetCursorPos(&pos);
ScreenToClient(hwnd, &pos);
GLenum err = glGetError();
while (glGetError() != GL_NO_ERROR) {cerr << err << endl;}
glReadPixels(pos.x, SCREEN_HEIGHT - 1 - pos.y, 1, 1, GL_RGB, GL_UNSIGNED_BYTE, &pixel[0] );
cerr << "r: "<< (int)pixel[0] << endl;
cerr << "g: "<< (int)pixel[1] << endl;
cerr << "b: "<< (int)pixel[2] << endl;
cerr << "a: "<< (int)pixel[3] << endl;
cout << pos.x << endl;
cout << pos.y << endl;
}
break;
I use :
WIN32 API
OPENGL 3.0
C++
