mu/ex11.mu

131 lines
4.4 KiB
Forth

# Demo of an interactive app: controlling a Bezier curve on screen
fn main screen: (addr screen), keyboard: (addr keyboard), data-disk: (addr disk) {
var env-storage: environment
var env/esi: (addr environment) <- address env-storage
initialize-environment env, 0x10 0x10, 0x80 0x100, 0x200 0x140
render screen, env
}
type environment {
p0: (handle point)
p1: (handle point)
p2: (handle point)
cursor: (handle point) # one of p0, p1 or p2
}
type point {
x: int
y: int
}
fn render screen: (addr screen), _self: (addr environment) {
var self/esi: (addr environment) <- copy _self
var tmp-ah/ecx: (addr handle point) <- get self, p0
var tmp/eax: (addr point) <- lookup *tmp-ah
var p0/ebx: (addr point) <- copy tmp
tmp-ah <- get self, p1
tmp <- lookup *tmp-ah
var p1/edx: (addr point) <- copy tmp
tmp-ah <- get self, p2
tmp <- lookup *tmp-ah
var p2/ecx: (addr point) <- copy tmp
# control lines
line screen, p0, p1, 7/color
line screen, p1, p2, 7/color
# curve above control lines
bezier screen, p0, p1, p2, 0xc/color
# points above curve
disc screen, p0, 3/radius, 7/color 0xf/border
disc screen, p1, 3/radius, 7/color 0xf/border
disc screen, p2, 3/radius, 7/color 0xf/border
# cursor last of all
var cursor-ah/eax: (addr handle point) <- get self, cursor
var cursor/eax: (addr point) <- lookup *cursor-ah
cursor screen, cursor, 0xa/side, 3/color
}
fn bezier screen: (addr screen), _p0: (addr point), _p1: (addr point), _p2: (addr point), color: int {
var p0/esi: (addr point) <- copy _p0
var x0/ecx: (addr int) <- get p0, x
var y0/edx: (addr int) <- get p0, y
var p1/esi: (addr point) <- copy _p1
var x1/ebx: (addr int) <- get p1, x
var y1/eax: (addr int) <- get p1, y
var p2/esi: (addr point) <- copy _p2
var x2/edi: (addr int) <- get p2, x
var y2/esi: (addr int) <- get p2, y
draw-monotonic-bezier screen, *x0 *y0, *x1 *y1, *x2 *y2, color
}
fn cursor screen: (addr screen), _p: (addr point), side: int, color: int {
var half-side/eax: int <- copy side
half-side <- shift-right 1
var p/esi: (addr point) <- copy _p
var x-a/ecx: (addr int) <- get p, x
var left-x/ecx: int <- copy *x-a
left-x <- subtract half-side
var y-a/edx: (addr int) <- get p, y
var top-y/edx: int <- copy *y-a
top-y <- subtract half-side
var max/eax: int <- copy left-x
max <- add side
draw-horizontal-line screen, top-y, left-x, max, color
max <- copy top-y
max <- add side
draw-vertical-line screen, left-x, top-y, max, color
var right-x/ebx: int <- copy left-x
right-x <- add side
draw-vertical-line screen, right-x, top-y, max, color
var bottom-y/edx: int <- copy top-y
bottom-y <- add side
draw-horizontal-line screen, bottom-y, left-x, right-x, color
}
fn line screen: (addr screen), _p0: (addr point), _p1: (addr point), color: int {
var p0/esi: (addr point) <- copy _p0
var x0/ecx: (addr int) <- get p0, x
var y0/edx: (addr int) <- get p0, y
var p1/esi: (addr point) <- copy _p1
var x1/ebx: (addr int) <- get p1, x
var y1/eax: (addr int) <- get p1, y
draw-line screen, *x0 *y0, *x1 *y1, color
}
fn disc screen: (addr screen), _p: (addr point), radius: int, color: int, border-color: int {
var p/esi: (addr point) <- copy _p
var x/ecx: (addr int) <- get p, x
var y/edx: (addr int) <- get p, y
draw-disc screen, *x *y, radius, color, border-color
}
fn initialize-environment _self: (addr environment), x0: int, y0: int, x1: int, y1: int, x2: int, y2: int {
var self/esi: (addr environment) <- copy _self
var p0-ah/eax: (addr handle point) <- get self, p0
allocate p0-ah
var p0/eax: (addr point) <- lookup *p0-ah
initialize-point p0, x0 y0
var p1-ah/eax: (addr handle point) <- get self, p1
allocate p1-ah
var p1/eax: (addr point) <- lookup *p1-ah
initialize-point p1, x1 y1
var p2-ah/eax: (addr handle point) <- get self, p2
allocate p2-ah
var p2/eax: (addr point) <- lookup *p2-ah
initialize-point p2, x2 y2
# cursor initially at p0
var cursor-ah/edi: (addr handle point) <- get self, cursor
var src-ah/esi: (addr handle point) <- get self, p0
copy-object src-ah, cursor-ah
}
fn initialize-point _p: (addr point), x: int, y: int {
var p/esi: (addr point) <- copy _p
var dest/eax: (addr int) <- get p, x
var src/ecx: int <- copy x
copy-to *dest, src
dest <- get p, y
src <- copy y
copy-to *dest, src
}