I'm not sure if I have a different version or something but what I have, the triangle is just a simple Triangle call to draw on screen.
Well, I remember he made a compatibility version that probably removed that surface so it would work faster in the then dx8 and GL drivers.
It used to draw gradient rectangles to the screen, but the last version just loads a pre-generated image, with the generating code commented out.
/* GradientRectangle(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT, COL_LIGHT_GREY, COL_DARK_GREY, COL_BLACK, COL_DARK_GREY);
var temp_back = GrabSurface(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
*/
// DEBUG
/* temp_back.save("bgi_" + SCREEN_WIDTH + "_" + SCREEN_HEIGHT + ".png");
Abort("bgi_" + SCREEN_WIDTH + "_" + SCREEN_HEIGHT + ".png");
*/
function PreRenderBackground ()
{
/* // Draw the main background
GradientRectangle(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT, COL_LIGHT_GREY, COL_DARK_GREY, COL_BLACK, COL_DARK_GREY);
// Draw the top bars
GradientRectangle(0, 0, SCREEN_WIDTH, mainFont.getHeight(), COL_LIGHT_GREY, COL_LIGHT_GREY, COL_DARK_GREY, COL_DARK_GREY);
GradientRectangle(0, mainFont.getHeight(), SCREEN_WIDTH, mainFont.getHeight(), COL_LIGHT_GREY, COL_LIGHT_GREY, COL_DARK_GREY, COL_DARK_GREY);
// Clock space
Rectangle(SCREEN_WIDTH - mainFont.getStringWidth(" 00:00:00"), 0, mainFont.getStringWidth(" 00:00:00"), mainFont.getHeight(), CreateColor(0, 0, 0, 32));
// Draw the Sphere icon box
GradientRectangle(0, 0, sphereIcon.width, sphereIcon.height, COL_LIGHT_GREY, COL_LIGHT_GREY, COL_DARK_GREY, COL_DARK_GREY);
// Draw the bottom bar
Rectangle(0, SCREEN_HEIGHT - mainFont.getHeight(), SCREEN_WIDTH, mainFont.getHeight(), CreateColor(0, 0, 0, 128));
// Store it and clear it
background = GrabSurface(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
Rectangle(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT, COL_BLACK);
*/
// DEBUG
/* background.save("bg_" + SCREEN_WIDTH + "_" + SCREEN_HEIGHT + ".png");
Abort("bg_" + SCREEN_WIDTH + "_" + SCREEN_HEIGHT + ".png");
*/
// Load the appropriate background instead
background = LoadSurface("bg_" + SCREEN_WIDTH + "_" + SCREEN_HEIGHT + ".png");
return;
}