gistfile1.txt

MAX_X = 320
MAX_Y = 240

POINT_A = {MAX_X/2, 0    } // top middle
POINT_B = {0,       MAX_Y} // bottom left
POINT_C = {MAX_X,   MAX_Y} // bottom right

// we greyscale, baby!
COLOR_A = 0
COLOR_B = 192
COLOR_C = 128

// for each scanline
for y in 0 .. MAX_Y:
    // the left edge of the scanline is y/MAX_Y of the distance
    // from the tip's x
    // to the left base point's x
    left_x = y/MAX_Y * (B.x - A.x) + A.x
    
    // the left edge's color is y/MAX_Y of the distance
    // from the tip's color
    // to the left base point's color
    left_color = y/MAX_Y * (COLOR_B - COLOR_A) + COLOR_A
    
    // the right edge of the scanline is y/MAX_Y of the distance
    // from the tip's x
    // to the right base point's x
    right_x = y/MAX_Y * (C.x - A.x) + A.x
    
    // the right edge's color is y/MAX_Y of the distance
    // from the tip's color
    // to the right base point's color
    right_color = y/MAX_Y * (COLOR_C - COLOR_A) + COLOR_A

    // for each pixel in the scanline
    for x in left_x to right_x:
        // the pixel's color is interpolated
        // from the left color to the right color
        color = (x - left_x)/(right_x - left_x) * (right_color - left_color) + left_color
        
        // now we can draw!
        drawPixel(x, y, color)