iris/source/ball.ccp

#pypp 0
#include <iris.hh>
#include <devices.hh>

static unsigned *framebuffer
static int const r = 10
static int colour

void ball (int x, int y, bool print):
	for int ty = y - r; ty < y + r; ++ty:
		if ty < 0 || ty >= 240:
			continue
		for int tx = x - r; tx < x + r; ++tx:
			if tx < 0 || tx >= 320:
				continue
			if (x - tx) * (x - tx) + (y - ty) * (y - ty) > r * r:
				continue
			framebuffer[ty * 320 + tx] = (print ? colour : 0)

Kernel::Num start ():
	Kernel::my_parent.init_done ()
	colour = 0xffffff
	framebuffer = (unsigned *)0x15000
	Display display = Kernel::my_parent.get_device <Display> (0x10000)
	int x = r, y = r, dx = 3, dy = 0
	Kernel::Cap eof = Kernel::my_receiver.create_capability (0)
	while true:
		display.set_eof_cb (eof)
		Kernel::wait ()
		ball (x, y, false)
		x += dx
		y += dy
		if y + r >= 240:
			dy = -dy
			y = 240 - r
		if x - r < 0:
			x = r
			dx = -dx
		if x + r >= 320:
			x = 320 - r
			dx = -dx
		if y == 240 - r && dy == 0:
			dy = -21
		++dy
		ball (x, y, true)