drawdotgraphics procedure

Syntax   drawdot (x, y, Color : int)

Description   The drawdot procedure is used to color the dot (pixel) at location (x, y) using the specified Color.

Example   This program randomly draws dots with random colors. The maxx, maxy and maxcolor functions give the maximum x, y and color values.

        setscreen ("graphics")
        var x, y, c : int
            randint (x, 0, maxx)        % Random x
            randint (y, 0, maxy)        % Random y
            randint (c, 0, maxcolor)    % Random color
            drawdot (x, y, c)
        end loop

Details   The screen should be in a "graphics" mode. If the screen is not in a "graphics" mode, it will automatically be set to "graphics" mode. See setscreen for details.

Example   This program draws a line of dots that bounce off the “sides” of the screen. It also demonstrates that you can use real coordinates to store position (x, y), as long as you convert the coordinates to int values using round in the drawdot call.

        var x, y : real
        var dx, dy : real
        var clr : int := 1
        x := Rand.Int (1, maxx - 1)
        y := Rand.Int (1, maxy - 1)
        dx := Rand.Real - 0.5
        dy := Rand.Real - 0.5
            drawdot (round (x), round (y), clr)
            clr := (clr + 1) mod maxcolor
            x := x + dx
            y := y + dy
            if x <= 0 or x >= maxx then
                dx := -dx
            end if
            if y <= 0 or y >= maxy then
                dy := -dy
            end if
        end loop

See also   setscreen, maxx, maxy and the various draw… procedures.