ref: 50746b16b551b78b0891a2be35be0f8796f2ad6f
dir: /libmemlayer/layerop.c/
#include <u.h> #include <libc.h> #include <draw.h> #include <memdraw.h> #include <memlayer.h> #define RECUR(a,b,c,d) _layerop(fn, i, Rect(a.x, b.y, c.x, d.y), clipr, etc, front->layer->rear); static void _layerop( void (*fn)(Memimage*, Rectangle, Rectangle, void*, int), Memimage *i, Rectangle r, Rectangle clipr, void *etc, Memimage *front) { Rectangle fr; Top: if(front == i){ /* no one is in front of this part of window; use the screen */ fn(i->layer->screen->image, r, clipr, etc, 0); return; } fr = front->layer->screenr; if(rectXrect(r, fr) == 0){ /* r doesn't touch this window; continue on next rearmost */ // assert(front && front->layer && front->layer->screen && front->layer->rear); front = front->layer->rear; goto Top; } if(fr.max.y < r.max.y){ RECUR(r.min, fr.max, r.max, r.max); r.max.y = fr.max.y; } if(r.min.y < fr.min.y){ RECUR(r.min, r.min, r.max, fr.min); r.min.y = fr.min.y; } if(fr.max.x < r.max.x){ RECUR(fr.max, r.min, r.max, r.max); r.max.x = fr.max.x; } if(r.min.x < fr.min.x){ RECUR(r.min, r.min, fr.min, r.max); r.min.x = fr.min.x; } /* r is covered by front, so put in save area */ (*fn)(i->layer->save, r, clipr, etc, 1); } /* * Assumes incoming rectangle has already been clipped to i's logical r and clipr */ void _memlayerop( void (*fn)(Memimage*, Rectangle, Rectangle, void*, int), Memimage *i, Rectangle screenr, /* clipped to window boundaries */ Rectangle clipr, /* clipped also to clipping rectangles of hierarchy */ void *etc) { Memlayer *l; Rectangle r, scr; l = i->layer; if(!rectclip(&screenr, l->screenr)) return; if(l->clear){ fn(l->screen->image, screenr, clipr, etc, 0); return; } r = screenr; scr = l->screen->image->clipr; /* * Do the piece on the screen */ if(rectclip(&screenr, scr)) _layerop(fn, i, screenr, clipr, etc, l->screen->frontmost); if(rectinrect(r, scr)) return; /* * Do the piece off the screen */ if(!rectXrect(r, scr)){ /* completely offscreen; easy */ fn(l->save, r, clipr, etc, 1); return; } if(r.min.y < scr.min.y){ /* above screen */ fn(l->save, Rect(r.min.x, r.min.y, r.max.x, scr.min.y), clipr, etc, 1); r.min.y = scr.min.y; } if(r.max.y > scr.max.y){ /* below screen */ fn(l->save, Rect(r.min.x, scr.max.y, r.max.x, r.max.y), clipr, etc, 1); r.max.y = scr.max.y; } if(r.min.x < scr.min.x){ /* left of screen */ fn(l->save, Rect(r.min.x, r.min.y, scr.min.x, r.max.y), clipr, etc, 1); r.min.x = scr.min.x; } if(r.max.x > scr.max.x){ /* right of screen */ fn(l->save, Rect(scr.max.x, r.min.y, r.max.x, r.max.y), clipr, etc, 1); } }