ref: b2d6fc35b198467f24f1d9316c75d39f0d05a959
parent: 8f13f227cd6169fc05bc5a59f0aafc4fc0551968
author: halfwit <michaelmisch1985@gmail.com>
date: Thu Oct 15 08:48:56 PDT 2020
Start porting the rest that we need
--- /dev/null
+++ b/libdraw/arith.c
@@ -1,0 +1,183 @@
+#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,
+};
+
+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;
--- a/libdraw/init.c
+++ b/libdraw/init.c
@@ -307,6 +307,7 @@
disp->opaque = disp->white;
disp->transparent = disp->black;
+ /* We still need this */
//dir = dirfstat(ctlfd);
//if(dir!=nil && dir->type=='i'){// disp->local = 1;