ref: e1854c96324dddac6911f1b49d16d83ba9e8831d
dir: /sys/src/libmemdraw/warptest.c/
#include <u.h> #include <libc.h> #include <draw.h> #include <memdraw.h> #include <geometry.h> uvlong t0; void profbegin(void) { char buf[128]; int fd; snprint(buf, sizeof(buf), "/proc/%d/ctl", getpid()); fd = open(buf, OWRITE); if(fd < 0) sysfatal("open: %r"); fprint(fd, "profile\n"); close(fd); t0 = nsec(); } void profend(void) { char buf[128]; double dt; dt = (nsec() - t0)/1e6; fprint(2, "dt: %fms\n", dt); snprint(buf, sizeof(buf), "%d", getpid()); switch(fork()){ case -1: abort(); case 0: dup(2, 1); print("tprof %s\n", buf); execl("/bin/tprof", "tprof", buf, nil); abort(); default: free(wait()); break; } } #define min(a,b) ((a)<(b)?(a):(b)) #define max(a,b) ((a)>(b)?(a):(b)) Rectangle getbbox(Rectangle *sr, Matrix m) { Point2 p0, p1, p2, p3; p0 = Pt2(sr->min.x, sr->min.y, 1); p0 = xform(p0, m); p1 = Pt2(sr->max.x, sr->min.y, 1); p1 = xform(p1, m); p2 = Pt2(sr->min.x, sr->max.y, 1); p2 = xform(p2, m); p3 = Pt2(sr->max.x, sr->max.y, 1); p3 = xform(p3, m); p0.x = min(min(min(p0.x, p1.x), p2.x), p3.x); p0.y = min(min(min(p0.y, p1.y), p2.y), p3.y); p1.x = max(max(max(p1.x, p1.x), p2.x), p3.x); p1.y = max(max(max(p1.y, p1.y), p2.y), p3.y); return Rect(p0.x, p0.y, p1.x, p1.y); } void usage(void) { fprint(2, "usage: %s [-s sx sy] [-t tx ty] [-r θ]\n", argv0); exits("usage"); } void main(int argc, char *argv[]) { Memimage *dst, *src; Rectangle dr; double sx, sy, tx, ty, θ, c, s; sx = sy = 1; tx = ty = 0; θ = 0; ARGBEGIN{ case 's': sx = strtod(EARGF(usage()), nil); sy = strtod(EARGF(usage()), nil); break; case 't': tx = strtod(EARGF(usage()), nil); ty = strtod(EARGF(usage()), nil); break; case 'r': θ = strtod(EARGF(usage()), nil)*DEG; break; default: usage(); }ARGEND; if(argc != 0) usage(); if(memimageinit() != 0) sysfatal("memimageinit: %r"); src = readmemimage(0); c = cos(θ); s = sin(θ); Matrix S = { sx, 0, 0, 0, sy, 0, 0, 0, 1, }, T = { 1, 0, tx, 0, 1, ty, 0, 0, 1, }, R = { c, -s, 0, s, c, 0, 0, 0, 1, }; mulm(S, R); mulm(T, S); // dr = getbbox(&src->r, T); dr = src->r; dst = allocmemimage(dr, src->chan); profbegin(); memaffinewarp(dst, dst->r, src, src->r.min, (uchar*)T); profend(); writememimage(1, dst); exits(nil); }