conterm/libdraw/arith.c

207 lines
2.8 KiB
C

#include <u.h>
#include <libc.h>
#include <draw.h>
Point
Pt(int x, int y)
{
Point p;
p.x = x;
p.y = y;
return p;
}
Rectangle
Rect(int x, int y, int bx, int by)
{
Rectangle r;
r.min.x = x;
r.min.y = y;
r.max.x = bx;
r.max.y = by;
return r;
}
Rectangle
Rpt(Point min, Point max)
{
Rectangle r;
r.min = min;
r.max = max;
return r;
}
Point
addpt(Point a, Point b)
{
a.x += b.x;
a.y += b.y;
return a;
}
Point
subpt(Point a, Point b)
{
a.x -= b.x;
a.y -= b.y;
return a;
}
Rectangle
insetrect(Rectangle r, int n)
{
r.min.x += n;
r.min.y += n;
r.max.x -= n;
r.max.y -= n;
return r;
}
Point
divpt(Point a, int b)
{
a.x /= b;
a.y /= b;
return a;
}
Point
mulpt(Point a, int b)
{
a.x *= b;
a.y *= b;
return a;
}
Rectangle
rectsubpt(Rectangle r, Point p)
{
r.min.x -= p.x;
r.min.y -= p.y;
r.max.x -= p.x;
r.max.y -= p.y;
return r;
}
Rectangle
rectaddpt(Rectangle r, Point p)
{
r.min.x += p.x;
r.min.y += p.y;
r.max.x += p.x;
r.max.y += p.y;
return r;
}
int
eqpt(Point p, Point q)
{
return p.x==q.x && p.y==q.y;
}
int
eqrect(Rectangle r, Rectangle s)
{
return r.min.x==s.min.x && r.max.x==s.max.x &&
r.min.y==s.min.y && r.max.y==s.max.y;
}
int
rectXrect(Rectangle r, Rectangle s)
{
return r.min.x<s.max.x && s.min.x<r.max.x &&
r.min.y<s.max.y && s.min.y<r.max.y;
}
int
rectinrect(Rectangle r, Rectangle s)
{
return s.min.x<=r.min.x && r.max.x<=s.max.x && s.min.y<=r.min.y && r.max.y<=s.max.y;
}
int
ptinrect(Point p, Rectangle r)
{
return p.x>=r.min.x && p.x<r.max.x &&
p.y>=r.min.y && p.y<r.max.y;
}
Rectangle
canonrect(Rectangle r)
{
int t;
if (r.max.x < r.min.x) {
t = r.min.x;
r.min.x = r.max.x;
r.max.x = t;
}
if (r.max.y < r.min.y) {
t = r.min.y;
r.min.y = r.max.y;
r.max.y = t;
}
return r;
}
void
combinerect(Rectangle *r1, Rectangle r2)
{
if(r1->min.x > r2.min.x)
r1->min.x = r2.min.x;
if(r1->min.y > r2.min.y)
r1->min.y = r2.min.y;
if(r1->max.x < r2.max.x)
r1->max.x = r2.max.x;
if(r1->max.y < r2.max.y)
r1->max.y = r2.max.y;
}
ulong
drawld2chan[] = {
GREY1,
GREY2,
GREY4,
CMAP8,
};
int log2[] = { -1, 0, 1, -1, 2, -1, -1, -1, 3, -1, -1, -1, -1, -1, -1, -1, 4, -1, -1, -1, -1, -1, -1, -1, 4 /* BUG */, -1, -1, -1, -1, -1, -1, -1, 5 };
ulong
setalpha(ulong color, uchar alpha)
{
int red, green, blue;
red = (color >> 3*8) & 0xFF;
green = (color >> 2*8) & 0xFF;
blue = (color >> 1*8) & 0xFF;
/* ignore incoming alpha */
red = (red * alpha)/255;
green = (green * alpha)/255;
blue = (blue * alpha)/255;
return (red<<3*8) | (green<<2*8) | (blue<<1*8) | (alpha<<0*8);
}
Point ZP;
Rectangle ZR;
int
Rfmt(Fmt *f)
{
Rectangle r;
r = va_arg(f->args, Rectangle);
return fmtprint(f, "%P %P", r.min, r.max);
}
int
Pfmt(Fmt *f)
{
Point p;
p = va_arg(f->args, Point);
return fmtprint(f, "[%d %d]", p.x, p.y);
}