HP Workstation zx2000 OpenGL 1.1 Reference for HP-UX 11.x - Page 30

B glBitMap 30 glBitMap glBitmap: draw a bitmap. C Specification void glBitmap( GLsizei width, GLsizei height, GLfloat xorig, GLfloat yorig, GLfloat xmove, GLfloat ymove, const GLubyte *bitmap) Parameters width, height xorig, yorig xmove, ymove bitmap Specify the pixel width and height of the bitmap image. Specify the location of the origin in the bitmap image. The origin is measured from the lower left corner of the bitmap, with right and up being the positive axes. Specify the x and y offsets to be added to the current raster position after the bitmap is drawn. Specifies the address of the bitmap image. Description A bitmap is a binary image. When drawn, the bitmap is positioned relative to the current raster position, and frame buffer pixels corresponding to 1s in the bitmap are written using the current raster color or index. Frame buffer pixels corresponding to 0s in the bitmap are not modified. glBitmap takes seven arguments. The first pair specifies the width and height of the bitmap image. The second pair specifies the location of the bitmap origin relative to the lower left corner of the bitmap image. The third pair of arguments specifies x and y offsets to be added to the current raster position after the bitmap has been drawn. The final argument is a pointer to the bitmap image itself. The bitmap image is interpreted like image data for the glDrawPixels command, with width and height corresponding to the width and height arguments of that command, and with type set to GL_BITMAP and format set to GL_COLOR_INDEX. Modes specified using glPixelStore affect the interpretation of bitmap image data; modes specified using glPixelTransfer do not. If the current raster position is invalid, glBitmap is ignored. Otherwise, the lower left corner of the bitmap image is positioned at the window coordinates xw = xr - xo yw =  yr - yo  Chapter 2