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burtonk
10-14-2012, 12:06 PM
So, I am trying to use glDrawPixels() to draw points on the screen but can't get it to work properly. Right now it draws the points I want, but then repeats the points in the same position on the y-axis but translated over a few pixels on the x-axis repeatedly.


I am creating a pixel buffer like so:



struct RGBType {
float r;
float g;
float b;
};

RGBType *pixel_buffer = new RGBType[800 * 1200];


Then filling in the rgb components I want to show up on the screen


pixel_buffer[800*y + x].r=0.5;
pixel_buffer[800*y + x].g=0.5;
pixel_buffer[800*y + x].b=0.5;


and then calling drawpixels and swapping the buffers


glDrawPixels(window_width, window_height, GL_RGB, GL_FLOAT, pixel_buffer);
glutSwapBuffers();
delete[] pixel_buffer;


All my other code is simply setting up a window with glut.

V-man
10-16-2012, 10:57 PM
Maybe you are using some other function that is causing the raster position to change. Call glRasterPos before calling glDrawPixels.