redraw.c moved to repo. Added licence notification

diff --git a/redraw.c b/redraw.c
new file mode 100755 (executable)
index 0000000..363bec0
--- /dev/null
+++ b/redraw.c
@@ -0,0 +1,117 @@
+/*
+   Copyright (C) Prikol Software 1996-1997
+   Copyright (C) Aleksey Volynskov 1996-1997
+   Copyright (C) <ARembo@gmail.com> 2011
+
+   This file is part of the Doom2D:Rembo project.
+
+   Doom2D:Rembo is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License version 2 as
+   published by the Free Software Foundation.
+
+   Doom2D:Rembo is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <http://www.gnu.org/licenses/> or
+   write to the Free Software Foundation, Inc.,
+   51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+*/
+
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+//#include "..\averr.h"
+#include "vga.h"
+#include "glob.h"
+/*
+#define MAXRECT 500
+
+typedef struct{short x,w,y,h;}rect;
+
+static rect *rt,*rp;
+static redraw_f *fn;
+static short sl,st,sr,sb;
+
+
+void *RD_init(short x,short w,short y,short h) {
+  rect *p;
+
+  if(!(p=malloc((MAXRECT*2+1)*sizeof(rect))))
+    {error(0,0,ENOMEM,NULL,NULL);return NULL;}//{error(EZ_VGALIB,ET_STD,ENOMEM,NULL,NULL);return NULL;}
+  p->x=x;p->w=x+w-1;p->y=y;p->h=y+h-1;
+  memset(p+1,0,MAXRECT*2*sizeof(rect));
+  return p;
+}
+
+void RD_start(void *p,redraw_f *f) {
+  rt=p;fn=f;
+  sl=rt->x;sr=rt->w;
+  st=rt->y;sb=rt->h;
+  ++rt;
+  rp=rt;
+}
+
+static void add(short x,short r,short y,short b) {
+  int i;
+  short rx,rr,ry,rb;
+
+  for(i=0;i<MAXRECT;++i) if(rp[i].w) {
+    if(x>(rr=(rx=rp[i].x)+rp[i].w-1)) continue;
+    if(r<rx) continue;
+    if(y>(rb=(ry=rp[i].y)+rp[i].h-1)) continue;
+    if(b<ry) continue;
+    if(x<rx) add(x,rx-1,y,b);
+    if(r>rr) add(rr+1,r,y,b);
+    if(y<ry) add(max(rx,x),min(rr,r),y,ry-1);
+    if(b>rb) add(max(rx,x),min(rr,r),rb+1,b);
+    return;
+  }
+  for(i=0;i<MAXRECT;++i) if(!rp[i].w) {
+    rp[i].x=x;rp[i].y=y;rp[i].w=r-x+1;rp[i].h=b-y+1;
+    return;
+  }
+}
+
+void RD_rect(short x,short w,short y,short h) {
+  if(x>sr) return;
+  if(x+w<=sl) return;
+  if(y>sb) return;
+  if(y+h<=st) return;
+  w+=x-1;h+=y-1;
+  if(x<sl) x=sl;
+  if(y<st) y=st;
+  if(w>sr) w=sr;
+  if(h>sb) h=sb;
+  add(x,w,y,h);
+}
+
+void RD_spr(short x,short y,vgaimg *v) {
+  RD_rect(x-v->sx,v->w,y-v->sy,v->h);
+}
+
+void RD_spr2(short x,short y,vgaimg *v) {
+  RD_rect(x-v->w+v->sx,v->w,y-v->sy,v->h);
+}
+
+void RD_end(void) {
+  int i;
+
+  V_setscr(scrbuf);
+  rp=rt+MAXRECT;
+  for(i=0;i<MAXRECT;++i) if(rt[i].w) {
+    add(rt[i].x,rt[i].x+rt[i].w-1,rt[i].y,rt[i].y+rt[i].h-1);
+  }
+  for(i=0;i<MAXRECT;++i) if(rp[i].w) {
+    scrx=rp[i].x;scrw=rp[i].w;scry=rp[i].y;scrh=rp[i].h;
+    fn();
+  }
+  for(i=0;i<MAXRECT;++i) if(rp[i].w) {
+    V_copytoscr(rp[i].x,rp[i].w,rp[i].y,rp[i].h);
+  }
+  memcpy(rp,rt,MAXRECT*sizeof(rect));
+  memset(rt,0,MAXRECT*sizeof(rect));
+}
+*/