X-Git-Url: http://git.imager.perl.org/imager.git/blobdiff_plain/a73aeb5fb8bf417b91c9f8e13905acf6a8692a37..8ceea84c875883b426fb102cb57a1e43e602b010:/draw.c

diff --git a/draw.c b/draw.c
index 1656105e..8cbe445d 100644
--- a/draw.c
+++ b/draw.c
@@ -1,15 +1,27 @@
-#include "image.h"
+#include "imager.h"
 #include "draw.h"
 #include "log.h"
+#include "imageri.h"
 
 #include <limits.h>
 
+static void
+cfill_from_btm(i_img *im, i_fill_t *fill, struct i_bitmap *btm, 
+	       int bxmin, int bxmax, int bymin, int bymax);
+
 void
 i_mmarray_cr(i_mmarray *ar,int l) {
   int i;
+  int alloc_size;
 
   ar->lines=l;
-  ar->data=mymalloc(sizeof(minmax)*l);
+  alloc_size = sizeof(minmax) * l;
+  /* check for overflow */
+  if (alloc_size / l != sizeof(minmax)) {
+    fprintf(stderr, "overflow calculating memory allocation");
+    exit(3);
+  }
+  ar->data=mymalloc(alloc_size); /* checked 5jul05 tonyc */
   for(i=0;i<l;i++) { ar->data[i].max=-1; ar->data[i].min=MAXINT; }
 }
 
@@ -50,19 +62,23 @@ void
 i_mmarray_render_fill(i_img *im,i_mmarray *ar,i_fill_t *fill) {
   int x, w, y;
   if (im->bits == i_8_bits && fill->fill_with_color) {
-    i_color *line = mymalloc(sizeof(i_color) * im->xsize);
+    i_color *line = mymalloc(sizeof(i_color) * im->xsize); /* checked 5jul05 tonyc */
     i_color *work = NULL;
     if (fill->combine)
-      work = mymalloc(sizeof(i_color) * im->xsize);
+      work = mymalloc(sizeof(i_color) * im->xsize); /* checked 5jul05 tonyc */
     for(y=0;y<ar->lines;y++) {
       if (ar->data[y].max!=-1) {
         x = ar->data[y].min;
         w = ar->data[y].max-ar->data[y].min;
 
-        if (fill->combine) 
+        if (fill->combine) {
           i_glin(im, x, x+w, y, line);
-        
-        (fill->fill_with_color)(fill, x, y, w, im->channels, line, work);
+          (fill->fill_with_color)(fill, x, y, w, im->channels, work);
+          (fill->combine)(line, work, im->channels, w);
+        }
+        else {
+          (fill->fill_with_color)(fill, x, y, w, im->channels, line);
+        }
         i_plin(im, x, x+w, y, line);
       }
     }
@@ -72,19 +88,23 @@ i_mmarray_render_fill(i_img *im,i_mmarray *ar,i_fill_t *fill) {
       myfree(work);
   }
   else {
-    i_fcolor *line = mymalloc(sizeof(i_fcolor) * im->xsize);
+    i_fcolor *line = mymalloc(sizeof(i_fcolor) * im->xsize); /* checked 5jul05 tonyc */
     i_fcolor *work = NULL;
     if (fill->combinef)
-      work = mymalloc(sizeof(i_fcolor) * im->xsize);
+      work = mymalloc(sizeof(i_fcolor) * im->xsize); /* checked 5jul05 tonyc */
     for(y=0;y<ar->lines;y++) {
       if (ar->data[y].max!=-1) {
         x = ar->data[y].min;
         w = ar->data[y].max-ar->data[y].min;
 
-        if (fill->combinef) 
+        if (fill->combinef) {
           i_glinf(im, x, x+w, y, line);
-        
-        (fill->fill_with_fcolor)(fill, x, y, w, im->channels, line, work);
+          (fill->fill_with_fcolor)(fill, x, y, w, im->channels, work);
+          (fill->combinef)(line, work, im->channels, w);
+        }
+        else {
+          (fill->fill_with_fcolor)(fill, x, y, w, im->channels, line);
+        }
         i_plinf(im, x, x+w, y, line);
       }
     }
@@ -103,14 +123,14 @@ i_arcdraw(int x1, int y1, int x2, int y2, i_mmarray *ar) {
   double dsec;
   int temp;
   alpha=(double)(y2-y1)/(double)(x2-x1);
-  if (fabs(alpha)<1) 
+  if (fabs(alpha) <= 1) 
     {
       if (x2<x1) { temp=x1; x1=x2; x2=temp; temp=y1; y1=y2; y2=temp; }
       dsec=y1;
-      while(x1<x2)
+      while(x1<=x2)
 	{
-	  dsec+=alpha;
 	  i_mmarray_add(ar,x1,(int)(dsec+0.5));
+	  dsec+=alpha;
 	  x1++;
 	}
     }
@@ -119,10 +139,10 @@ i_arcdraw(int x1, int y1, int x2, int y2, i_mmarray *ar) {
       alpha=1/alpha;
       if (y2<y1) { temp=x1; x1=x2; x2=temp; temp=y1; y1=y2; y2=temp; }
       dsec=x1;
-      while(y1<y2)
+      while(y1<=y2)
 	{
-	  dsec+=alpha;
 	  i_mmarray_add(ar,(int)(dsec+0.5),y1);
+	  dsec+=alpha;
 	  y1++;
 	}
     }
@@ -135,16 +155,15 @@ i_mmarray_info(i_mmarray *ar) {
   if (ar->data[i].max!=-1) printf("line %d: min=%d, max=%d.\n",i,ar->data[i].min,ar->data[i].max);
 }
 
-
-void
-i_arc(i_img *im,int x,int y,float rad,float d1,float d2,i_color *val) {
+static void
+i_arc_minmax(i_int_hlines *hlines,int x,int y,float rad,float d1,float d2) {
   i_mmarray dot;
   float f,fx,fy;
   int x1,y1;
 
-  mm_log((1,"i_arc(im* 0x%x,x %d,y %d,rad %.2f,d1 %.2f,d2 %.2f,val 0x%x)\n",im,x,y,rad,d1,d2,val));
+  /*mm_log((1,"i_arc(im* 0x%x,x %d,y %d,rad %.2f,d1 %.2f,d2 %.2f,val 0x%x)\n",im,x,y,rad,d1,d2,val));*/
 
-  i_mmarray_cr(&dot,im->ysize);
+  i_mmarray_cr(&dot, hlines->limit_y);
 
   x1=(int)(x+0.5+rad*cos(d1*PI/180.0));
   y1=(int)(y+0.5+rad*sin(d1*PI/180.0));
@@ -161,51 +180,213 @@ i_arc(i_img *im,int x,int y,float rad,float d1,float d2,i_color *val) {
   /*  printf("x1: %d.\ny1: %d.\n",x1,y1); */
   i_arcdraw(x, y, x1, y1, &dot);
 
+  /* render the minmax values onto the hlines */
+  for (y = 0; y < dot.lines; y++) {
+    if (dot.data[y].max!=-1) {
+      int minx, width;
+      minx = dot.data[y].min;
+      width = dot.data[y].max - dot.data[y].min + 1;
+      i_int_hlines_add(hlines, y, minx, width);
+    }
+  }
+
   /*  dot.info(); */
-  i_mmarray_render(im,&dot,val);
   i_mmarray_dst(&dot);
 }
 
+static void
+i_arc_hlines(i_int_hlines *hlines,int x,int y,float rad,float d1,float d2) {
+  if (d1 <= d2) {
+    i_arc_minmax(hlines, x, y, rad, d1, d2);
+  }
+  else {
+    i_arc_minmax(hlines, x, y, rad, d1, 360);
+    i_arc_minmax(hlines, x, y, rad, 0, d2);
+  }
+}
+
+/*
+=item i_arc(im, x, y, rad, d1, d2, color)
+
+=category Drawing
+=synopsis i_arc(im, 50, 50, 20, 45, 135, &color);
+
+Fills an arc centered at (x,y) with radius I<rad> covering the range
+of angles in degrees from d1 to d2, with the color.
+
+=cut
+*/
+
+void
+i_arc(i_img *im,int x,int y,float rad,float d1,float d2,const i_color *val) {
+  i_int_hlines hlines;
+
+  i_int_init_hlines_img(&hlines, im);
+
+  i_arc_hlines(&hlines, x, y, rad, d1, d2);
+
+  i_int_hlines_fill_color(im, &hlines, val);
+
+  i_int_hlines_destroy(&hlines);
+}
+
+/*
+=item i_arc_cfill(im, x, y, rad, d1, d2, fill)
+
+=category Drawing
+=synopsis i_arc_cfill(im, 50, 50, 35, 90, 135, fill);
+
+Fills an arc centered at (x,y) with radius I<rad> covering the range
+of angles in degrees from d1 to d2, with the fill object.
+
+=cut
+*/
+
+#define MIN_CIRCLE_STEPS 8
+#define MAX_CIRCLE_STEPS 360
+
 void
 i_arc_cfill(i_img *im,int x,int y,float rad,float d1,float d2,i_fill_t *fill) {
-  i_mmarray dot;
-  float f,fx,fy;
-  int x1,y1;
+  i_int_hlines hlines;
 
-  mm_log((1,"i_arc_cfill(im* 0x%x,x %d,y %d,rad %.2f,d1 %.2f,d2 %.2f,fill 0x%x)\n",im,x,y,rad,d1,d2,fill));
+  i_int_init_hlines_img(&hlines, im);
 
-  i_mmarray_cr(&dot,im->ysize);
+  i_arc_hlines(&hlines, x, y, rad, d1, d2);
 
-  x1=(int)(x+0.5+rad*cos(d1*PI/180.0));
-  y1=(int)(y+0.5+rad*sin(d1*PI/180.0));
-  fx=(float)x1; fy=(float)y1;
+  i_int_hlines_fill_fill(im, &hlines, fill);
 
-  /*  printf("x1: %d.\ny1: %d.\n",x1,y1); */
-  i_arcdraw(x, y, x1, y1, &dot);
+  i_int_hlines_destroy(&hlines);
+}
 
-  x1=(int)(x+0.5+rad*cos(d2*PI/180.0));
-  y1=(int)(y+0.5+rad*sin(d2*PI/180.0));
+static void
+arc_poly(int *count, double **xvals, double **yvals,
+	 double x, double y, double rad, double d1, double d2) {
+  double d1_rad, d2_rad;
+  double circum;
+  int steps, point_count;
+  double angle_inc;
+
+  /* normalize the angles */
+  d1 = fmod(d1, 360);
+  if (d1 == 0) {
+    if (d2 >= 360) { /* default is 361 */
+      d2 = 360;
+    }
+    else {
+      d2 = fmod(d2, 360);
+      if (d2 < d1)
+	d2 += 360;
+    }
+  }
+  else {
+    d2 = fmod(d2, 360);
+    if (d2 < d1)
+      d2 += 360;
+  }
+  d1_rad = d1 * PI / 180;
+  d2_rad = d2 * PI / 180;
+
+  /* how many segments for the curved part? 
+     we do a maximum of one per degree, with a minimum of 8/circle
+     we try to aim at having about one segment per 2 pixels
+     Work it out per circle to get a step size.
+
+     I was originally making steps = circum/2 but that looked horrible.
+
+     I think there might be an issue in the polygon filler.
+  */
+  circum = 2 * PI * rad;
+  steps = circum;
+  if (steps > MAX_CIRCLE_STEPS)
+    steps = MAX_CIRCLE_STEPS;
+  else if (steps < MIN_CIRCLE_STEPS)
+    steps = MIN_CIRCLE_STEPS;
+
+  angle_inc = 2 * PI / steps;
+
+  point_count = steps + 5; /* rough */
+  /* point_count is always relatively small, so allocation won't overflow */
+  *xvals = mymalloc(point_count * sizeof(double)); /* checked 17feb2005 tonyc */
+  *yvals = mymalloc(point_count * sizeof(double)); /* checked 17feb2005 tonyc */
+
+  /* from centre to edge at d1 */
+  (*xvals)[0] = x;
+  (*yvals)[0] = y;
+  (*xvals)[1] = x + rad * cos(d1_rad);
+  (*yvals)[1] = y + rad * sin(d1_rad);
+  *count = 2;
+
+  /* step around the curve */
+  while (d1_rad < d2_rad) {
+    (*xvals)[*count] = x + rad * cos(d1_rad);
+    (*yvals)[*count] = y + rad * sin(d1_rad);
+    ++*count;
+    d1_rad += angle_inc;
+  }
 
-  for(f=d1;f<=d2;f+=0.01) i_mmarray_add(&dot,(int)(x+0.5+rad*cos(f*PI/180.0)),(int)(y+0.5+rad*sin(f*PI/180.0)));
-  
-  /*  printf("x1: %d.\ny1: %d.\n",x1,y1); */
-  i_arcdraw(x, y, x1, y1, &dot);
+  /* finish off the curve */
+  (*xvals)[*count] = x + rad * cos(d2_rad);
+  (*yvals)[*count] = y + rad * sin(d2_rad);
+  ++*count;
+}
 
-  /*  dot.info(); */
-  i_mmarray_render_fill(im,&dot,fill);
-  i_mmarray_dst(&dot);
+/*
+=item i_arc_aa(im, x, y, rad, d1, d2, color)
+
+=category Drawing
+=synopsis i_arc_aa(im, 50, 50, 35, 90, 135, &color);
+
+Antialias fills an arc centered at (x,y) with radius I<rad> covering
+the range of angles in degrees from d1 to d2, with the color.
+
+=cut
+*/
+
+void
+i_arc_aa(i_img *im, double x, double y, double rad, double d1, double d2,
+	 const i_color *val) {
+  double *xvals, *yvals;
+  int count;
+
+  arc_poly(&count, &xvals, &yvals, x, y, rad, d1, d2);
+
+  i_poly_aa(im, count, xvals, yvals, val);
+
+  myfree(xvals);
+  myfree(yvals);
 }
 
+/*
+=item i_arc_aa_cfill(im, x, y, rad, d1, d2, fill)
+
+=category Drawing
+=synopsis i_arc_aa_cfill(im, 50, 50, 35, 90, 135, fill);
+
+Antialias fills an arc centered at (x,y) with radius I<rad> covering
+the range of angles in degrees from d1 to d2, with the fill object.
+
+=cut
+*/
+
+void
+i_arc_aa_cfill(i_img *im, double x, double y, double rad, double d1, double d2,
+	       i_fill_t *fill) {
+  double *xvals, *yvals;
+  int count;
+
+  arc_poly(&count, &xvals, &yvals, x, y, rad, d1, d2);
+
+  i_poly_aa_cfill(im, count, xvals, yvals, fill);
 
+  myfree(xvals);
+  myfree(yvals);
+}
 
 /* Temporary AA HACK */
 
 
 typedef int frac;
 static  frac float_to_frac(float x) { return (frac)(0.5+x*16.0); }
-static   int frac_sub     (frac x)  { return (x%16); }
-static   int frac_int     (frac x)  { return (x/16); }
-static float frac_to_float(float x) { return (float)x/16.0; }
 
 static 
 void
@@ -214,19 +395,6 @@ polar_to_plane(float cx, float cy, float angle, float radius, frac *x, frac *y)
   *y = float_to_frac(cy+radius*sin(angle));
 }
 
-static
-void
-order_pair(frac *x, frac *y) {
-  frac t = *x;
-  if (t>*y) {
-    *x = *y;
-    *y = t;
-  }
-}
-
-
-
-
 static
 void
 make_minmax_list(i_mmarray *dot, float x, float y, float radius) {
@@ -239,7 +407,6 @@ make_minmax_list(i_mmarray *dot, float x, float y, float radius) {
   polar_to_plane(x, y, angle, radius, &sx, &sy);
   
   for(angle = 0.0; angle<361; angle +=astep) {
-    float alpha;
     lx = sx; ly = sy;
     polar_to_plane(x, y, angle, radius, &cx, &cy);
     sx = cx; sy = cy;
@@ -295,8 +462,19 @@ i_pixel_coverage(i_mmarray *dot, int x, int y) {
   return cnt;
 }
 
+/*
+=item i_circle_aa(im, x, y, rad, color)
+
+=category Drawing
+=synopsis i_circle_aa(im, 50, 50, 45, &color);
+
+Antialias fills a circle centered at (x,y) for radius I<rad> with
+color.
+
+=cut
+*/
 void
-i_circle_aa(i_img *im, float x, float y, float rad, i_color *val) {
+i_circle_aa(i_img *im, float x, float y, float rad, const i_color *val) {
   i_mmarray dot;
   i_color temp;
   int ly;
@@ -307,7 +485,7 @@ i_circle_aa(i_img *im, float x, float y, float rad, i_color *val) {
   make_minmax_list(&dot, x, y, rad);
 
   for(ly = 0; ly<im->ysize; ly++) {
-    int ix, cy, cnt = 0, minx = INT_MAX, maxx = INT_MIN;
+    int ix, cy, minx = INT_MAX, maxx = INT_MIN;
 
     /* Find the left/rightmost set subpixels */
     for(cy = 0; cy<16; cy++) {
@@ -335,15 +513,22 @@ i_circle_aa(i_img *im, float x, float y, float rad, i_color *val) {
       }
     }
   }
+  i_mmarray_dst(&dot);
 }
 
+/*
+=item i_box(im, x1, y1, x2, y2, color)
 
+=category Drawing
+=synopsis i_box(im, 0, 0, im->xsize-1, im->ysize-1, &color).
 
+Outlines the box from (x1,y1) to (x2,y2) inclusive with I<color>.
 
-
+=cut
+*/
 
 void
-i_box(i_img *im,int x1,int y1,int x2,int y2,i_color *val) {
+i_box(i_img *im,int x1,int y1,int x2,int y2,const i_color *val) {
   int x,y;
   mm_log((1,"i_box(im* 0x%x,x1 %d,y1 %d,x2 %d,y2 %d,val 0x%x)\n",im,x1,y1,x2,y2,val));
   for(x=x1;x<x2+1;x++) {
@@ -356,28 +541,64 @@ i_box(i_img *im,int x1,int y1,int x2,int y2,i_color *val) {
   }
 }
 
+/*
+=item i_box_filled(im, x1, y1, x2, y2, color)
+
+=category Drawing
+=synopsis i_box_filled(im, 0, 0, im->xsize-1, im->ysize-1, &color);
+
+Fills the box from (x1,y1) to (x2,y2) inclusive with color.
+
+=cut
+*/
+
 void
-i_box_filled(i_img *im,int x1,int y1,int x2,int y2,i_color *val) {
+i_box_filled(i_img *im,int x1,int y1,int x2,int y2, const i_color *val) {
   int x,y;
   mm_log((1,"i_box_filled(im* 0x%x,x1 %d,y1 %d,x2 %d,y2 %d,val 0x%x)\n",im,x1,y1,x2,y2,val));
   for(x=x1;x<x2+1;x++) for (y=y1;y<y2+1;y++) i_ppix(im,x,y,val);
 }
 
+/*
+=item i_box_cfill(im, x1, y1, x2, y2, fill)
+
+=category Drawing
+=synopsis i_box_cfill(im, 0, 0, im->xsize-1, im->ysize-1, fill);
+
+Fills the box from (x1,y1) to (x2,y2) inclusive with fill.
+
+=cut
+*/
+
 void
 i_box_cfill(i_img *im,int x1,int y1,int x2,int y2,i_fill_t *fill) {
   mm_log((1,"i_box_cfill(im* 0x%x,x1 %d,y1 %d,x2 %d,y2 %d,fill 0x%x)\n",im,x1,y1,x2,y2,fill));
 
   ++x2;
+  if (x1 < 0)
+    x1 = 0;
+  if (y1 < 0) 
+    y1 = 0;
+  if (x2 > im->xsize) 
+    x2 = im->xsize;
+  if (y2 >= im->ysize)
+    y2 = im->ysize-1;
+  if (x1 >= x2 || y1 > y2)
+    return;
   if (im->bits == i_8_bits && fill->fill_with_color) {
-    i_color *line = mymalloc(sizeof(i_color) * (x2 - x1));
+    i_color *line = mymalloc(sizeof(i_color) * (x2 - x1)); /* checked 5jul05 tonyc */
     i_color *work = NULL;
     if (fill->combine)
-      work = mymalloc(sizeof(i_color) * (x2-x1));
+      work = mymalloc(sizeof(i_color) * (x2-x1)); /* checked 5jul05 tonyc */
     while (y1 <= y2) {
-      if (fill->combine)
+      if (fill->combine) {
         i_glin(im, x1, x2, y1, line);
-
-      (fill->fill_with_color)(fill, x1, y1, x2-x1, im->channels, line, work);
+        (fill->fill_with_color)(fill, x1, y1, x2-x1, im->channels, work);
+        (fill->combine)(line, work, im->channels, x2-x1);
+      }
+      else {
+        (fill->fill_with_color)(fill, x1, y1, x2-x1, im->channels, line);
+      }
       i_plin(im, x1, x2, y1, line);
       ++y1;
     }
@@ -386,15 +607,19 @@ i_box_cfill(i_img *im,int x1,int y1,int x2,int y2,i_fill_t *fill) {
       myfree(work);
   }
   else {
-    i_fcolor *line = mymalloc(sizeof(i_fcolor) * (x2 - x1));
+    i_fcolor *line = mymalloc(sizeof(i_fcolor) * (x2 - x1)); /* checked 5jul05 tonyc */
     i_fcolor *work;
-    work = mymalloc(sizeof(i_fcolor) * (x2 - x1));
+    work = mymalloc(sizeof(i_fcolor) * (x2 - x1)); /* checked 5jul05 tonyc */
 
     while (y1 <= y2) {
-      if (fill->combinef)
+      if (fill->combine) {
         i_glinf(im, x1, x2, y1, line);
-
-      (fill->fill_with_fcolor)(fill, x1, y1, x2-x1, im->channels, line, work);
+        (fill->fill_with_fcolor)(fill, x1, y1, x2-x1, im->channels, work);
+        (fill->combinef)(line, work, im->channels, x2-x1);
+      }
+      else {
+        (fill->fill_with_fcolor)(fill, x1, y1, x2-x1, im->channels, line);
+      }
       i_plinf(im, x1, x2, y1, line);
       ++y1;
     }
@@ -404,49 +629,161 @@ i_box_cfill(i_img *im,int x1,int y1,int x2,int y2,i_fill_t *fill) {
   }
 }
 
+
+/* 
+=item i_line(im, x1, y1, x2, y2, val, endp)
+
+=category Drawing
+
+Draw a line to image using bresenhams linedrawing algorithm
+
+   im   - image to draw to
+   x1   - starting x coordinate
+   y1   - starting x coordinate
+   x2   - starting x coordinate
+   y2   - starting x coordinate
+   val  - color to write to image
+   endp - endpoint flag (boolean)
+
+=cut
+*/
+
 void
-i_draw(i_img *im,int x1,int y1,int x2,int y2,i_color *val) {
-  double alpha;
-  double dsec;
-  int temp;
+i_line(i_img *im, int x1, int y1, int x2, int y2, const i_color *val, int endp) {
+  int x, y;
+  int dx, dy;
+  int p;
 
-  mm_log((1,"i_draw(im* 0x%x,x1 %d,y1 %d,x2 %d,y2 %d,val 0x%x)\n",im,x1,y1,x2,y2,val));
+  dx = x2 - x1;
+  dy = y2 - y1;
 
-  alpha=(double)(y2-y1)/(double)(x2-x1);
-  if (fabs(alpha)<1) 
-    {
-      if (x2<x1) { temp=x1; x1=x2; x2=temp; temp=y1; y1=y2; y2=temp; }
-      dsec=y1;
-      while(x1<x2)
-	{
-	  dsec+=alpha;
-	  i_ppix(im,x1,(int)(dsec+0.5),val);
-	  x1++;
-	}
+
+  /* choose variable to iterate on */
+  if (abs(dx)>abs(dy)) {
+    int dx2, dy2, cpy;
+
+    /* sort by x */
+    if (x1 > x2) {
+      int t;
+      t = x1; x1 = x2; x2 = t;
+      t = y1; y1 = y2; y2 = t;
     }
-  else
-    {
-      alpha=1/alpha;
-      if (y2<y1) { temp=x1; x1=x2; x2=temp; temp=y1; y1=y2; y2=temp; }
-      dsec=x1;
-      while(y1<y2)
-	{
-	  dsec+=alpha;
-	  i_ppix(im,(int)(dsec+0.5),y1,val);
-	  y1++;
-	}
+    
+    dx = abs(dx);
+    dx2 = dx*2;
+    dy = y2 - y1;
+
+    if (dy<0) {
+      dy = -dy;
+      cpy = -1;
+    } else {
+      cpy = 1;
+    }
+    dy2 = dy*2;
+    p = dy2 - dx;
+
+    
+    y = y1;
+    for(x=x1; x<x2-1; x++) {
+      if (p<0) {
+        p += dy2;
+      } else {
+        y += cpy;
+        p += dy2-dx2;
+      }
+      i_ppix(im, x+1, y, val);
     }
-  mm_log((1,"i_draw: alpha=%f.\n",alpha));
+  } else {
+    int dy2, dx2, cpx;
+
+    /* sort bx y */
+    if (y1 > y2) {
+      int t;
+      t = x1; x1 = x2; x2 = t;
+      t = y1; y1 = y2; y2 = t;
+    }
+    
+    dy = abs(dy);
+    dx = x2 - x1;
+    dy2 = dy*2;
+
+    if (dx<0) {
+      dx = -dx;
+      cpx = -1;
+    } else {
+      cpx = 1;
+    }
+    dx2 = dx*2;
+    p = dx2 - dy;
+
+    x = x1;
+    
+    for(y=y1; y<y2-1; y++) {
+      if (p<0) {
+        p  += dx2;
+      } else {
+        x += cpx;
+        p += dx2-dy2;
+      }
+      i_ppix(im, x, y+1, val);
+    }
+  }
+  if (endp) {
+    i_ppix(im, x1, y1, val);
+    i_ppix(im, x2, y2, val);
+  } else {
+    if (x1 != x2 || y1 != y2) 
+      i_ppix(im, x1, y1, val);
+  }
 }
+
+
+void
+i_line_dda(i_img *im, int x1, int y1, int x2, int y2, i_color *val) {
+
+  float dy;
+  int x;
+  
+  for(x=x1; x<=x2; x++) {
+    dy = y1+ (x-x1)/(float)(x2-x1)*(y2-y1);
+    i_ppix(im, x, (int)(dy+0.5), val);
+  }
+}
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
 
 void
-i_line_aa(i_img *im,int x1,int y1,int x2,int y2,i_color *val) {
+i_line_aa3(i_img *im,int x1,int y1,int x2,int y2,i_color *val) {
   i_color tval;
   float alpha;
   float dsec,dfrac;
   int temp,dx,dy,isec,ch;
 
-  mm_log((1,"i_draw(im* 0x%x,x1 %d,y1 %d,x2 %d,y2 %d,val 0x%x)\n",im,x1,y1,x2,y2,val));
+  mm_log((1,"i_line_aa(im* 0x%x,x1 %d,y1 %d,x2 %d,y2 %d,val 0x%x)\n",im,x1,y1,x2,y2,val));
 
   dy=y2-y1;
   dx=x2-x1;
@@ -496,7 +833,148 @@ i_line_aa(i_img *im,int x1,int y1,int x2,int y2,i_color *val) {
   }
 }
 
-double
+
+/*
+=item i_line_aa(im, x1, x2, y1, y2, color, endp)
+
+=category Drawing
+
+Antialias draws a line from (x1,y1) to (x2, y2) in color.
+
+The point (x2, y2) is drawn only if endp is set.
+
+=cut
+*/
+
+void
+i_line_aa(i_img *im, int x1, int y1, int x2, int y2, const i_color *val, int endp) {
+  int x, y;
+  int dx, dy;
+  int p;
+
+  dx = x2 - x1;
+  dy = y2 - y1;
+
+  /* choose variable to iterate on */
+  if (abs(dx)>abs(dy)) {
+    int dx2, dy2, cpy;
+    
+    /* sort by x */
+    if (x1 > x2) {
+      int t;
+      t = x1; x1 = x2; x2 = t;
+      t = y1; y1 = y2; y2 = t;
+    }
+    
+    dx = abs(dx);
+    dx2 = dx*2;
+    dy = y2 - y1;
+
+    if (dy<0) {
+      dy = -dy;
+      cpy = -1;
+    } else {
+      cpy = 1;
+    }
+    dy2 = dy*2;
+    p = dy2 - dx2; /* this has to be like this for AA */
+    
+    y = y1;
+
+    for(x=x1; x<x2-1; x++) {
+      int ch;
+      i_color tval;
+      float t = (dy) ? -(float)(p)/(float)(dx2) : 1;
+      float t1, t2;
+
+      if (t<0) t = 0;
+      t1 = 1-t;
+      t2 = t;
+
+      i_gpix(im,x+1,y,&tval);
+      for(ch=0;ch<im->channels;ch++)
+	tval.channel[ch]=(unsigned char)(t1*(float)tval.channel[ch]+t2*(float)val->channel[ch]);
+      i_ppix(im,x+1,y,&tval);
+
+      i_gpix(im,x+1,y+cpy,&tval);
+      for(ch=0;ch<im->channels;ch++)
+	tval.channel[ch]=(unsigned char)(t2*(float)tval.channel[ch]+t1*(float)val->channel[ch]);
+      i_ppix(im,x+1,y+cpy,&tval);
+
+      if (p<0) {
+        p += dy2;
+      } else {
+        y += cpy;
+        p += dy2-dx2;
+      }
+    }
+  } else {
+    int dy2, dx2, cpx;
+
+    /* sort bx y */
+    if (y1 > y2) {
+      int t;
+      t = x1; x1 = x2; x2 = t;
+      t = y1; y1 = y2; y2 = t;
+    }
+    
+    dy = abs(dy);
+    dx = x2 - x1;
+    dy2 = dy*2;
+
+    if (dx<0) {
+      dx = -dx;
+      cpx = -1;
+    } else {
+      cpx = 1;
+    }
+    dx2 = dx*2;
+    p = dx2 - dy2; /* this has to be like this for AA */
+
+    x = x1;
+    
+    for(y=y1; y<y2-1; y++) {
+      int ch;
+      i_color tval;
+      float t = (dx) ? -(float)(p)/(float)(dy2) : 1;
+      float t1, t2;
+      
+      if (t<0) t = 0;
+      t1 = 1-t;
+      t2 = t;
+
+      i_gpix(im,x,y+1,&tval);
+      for(ch=0;ch<im->channels;ch++)
+	tval.channel[ch]=(unsigned char)(t1*(float)tval.channel[ch]+t2*(float)val->channel[ch]);
+      i_ppix(im,x,y+1,&tval);
+
+      i_gpix(im,x+cpx,y+1,&tval);
+      for(ch=0;ch<im->channels;ch++)
+	tval.channel[ch]=(unsigned char)(t2*(float)tval.channel[ch]+t1*(float)val->channel[ch]);
+      i_ppix(im,x+cpx,y+1,&tval);
+
+      if (p<0) {
+        p  += dx2;
+      } else {
+        x += cpx;
+        p += dx2-dy2;
+      }
+    }
+  }
+
+
+  if (endp) {
+    i_ppix(im, x1, y1, val);
+    i_ppix(im, x2, y2, val);
+  } else {
+    if (x1 != x2 || y1 != y2) 
+      i_ppix(im, x1, y1, val);
+  }
+}
+
+
+
+static double
 perm(int n,int k) {
   double r;
   int i;
@@ -513,7 +991,7 @@ perm(int n,int k) {
    to get a new level - this may lead to errors who knows lets test it */
 
 void
-i_bezier_multi(i_img *im,int l,double *x,double *y,i_color *val) {
+i_bezier_multi(i_img *im,int l,const double *x,const double *y, const i_color *val) {
   double *bzcoef;
   double t,cx,cy;
   int k,i;
@@ -521,8 +999,8 @@ i_bezier_multi(i_img *im,int l,double *x,double *y,i_color *val) {
   int n=l-1;
   double itr,ccoef;
 
-
-  bzcoef=mymalloc(sizeof(double)*l);
+  /* this is the same size as the x and y arrays, so shouldn't overflow */
+  bzcoef=mymalloc(sizeof(double)*l); /* checked 5jul05 tonyc */
   for(k=0;k<l;k++) bzcoef[k]=perm(n,k);
   ICL_info(val);
 
@@ -543,7 +1021,7 @@ i_bezier_multi(i_img *im,int l,double *x,double *y,i_color *val) {
     }
     /*    printf("%f -> (%d,%d)\n",t,(int)(0.5+cx),(int)(0.5+cy)); */
     if (i++) { 
-      i_line_aa(im,lx,ly,(int)(0.5+cx),(int)(0.5+cy),val);
+      i_line_aa(im,lx,ly,(int)(0.5+cx),(int)(0.5+cy),val, 1);
     }
       /*     i_ppix(im,(int)(0.5+cx),(int)(0.5+cy),val); */
     lx=(int)(0.5+cx);
@@ -553,8 +1031,6 @@ i_bezier_multi(i_img *im,int l,double *x,double *y,i_color *val) {
   myfree(bzcoef);
 }
 
-
-
 /* Flood fill 
 
    REF: Graphics Gems I. page 282+
@@ -573,329 +1049,6 @@ i_bezier_multi(i_img *im,int l,double *x,double *y,i_color *val) {
 */
 
 
-
-
-#define IMTRUNC(x) ((int)(x*16))
-
-
-/*
-typedef struct {
-  short ms,ls;
-} pcord;
-*/
-
-typedef int pcord;
-
-struct p_point {
-  int n;
-  pcord x,y;
-};
-
-struct p_line  {
-  int n;
-  pcord x1,y1;
-  pcord x2,y2;
-  pcord miny,maxy;
-};
-
-struct p_slice {
-  int n;
-  double x;
-};
-
-int
-p_compy(const struct p_point *p1, const struct p_point *p2) {
-  if (p1->y > p2->y) return 1;
-  if (p1->y < p2->y) return -1;
-  return 0;
-}
-
-int
-p_compx(const struct p_slice *p1, const struct p_slice *p2) {
-  if (p1->x > p2->x) return 1;
-  if (p1->x < p2->x) return -1;
-  return 0;
-}
-
-/* Change this to int? and round right goddamn it! */
-
-double
-p_eval_aty(struct p_line *l,pcord y) {
-  int t;
-  t=l->y2-l->y1;
-  if (t) return ( (y-l->y1)*l->x2 + (l->y2-y)*l->x1 )/t;
-  return (l->x1+l->x2)/2.0;
-}
-
-double
-p_eval_atx(struct p_line *l,pcord x) {
-  int t;
-  t=l->x2-l->x1;
-  if (t) return ( (x-l->x1)*l->y2 + (l->x2-x)*l->y1 )/t;
-  return (l->y1+l->y2)/2.0;
-}
-
-
-/* Algorithm to count the pixels covered by line going through pixel (x,y)
-   in coarse coords.
-*/
-
-/*
-static int
-p_eval_coverage(struct p_line *l, int lc, int x, pcord y1, pcord y2) {
-
-  return 0;
-}
-*/
-
-
-/* Antialiasing polygon algorithm 
-   specs:
-     1. only nice polygons - no crossovers
-     2. 1/16 pixel resolution # previously - floating point co-ordinates
-     3. full antialiasing ( complete spectrum of blends )
-     4. uses hardly any memory
-     5. no subsampling phase
-
-   For each interval we must: 
-     1. find which lines are in it
-     2. order the lines from in increasing x order.
-        since we are assuming no crossovers it is sufficent
-        to check a single point on each line.
-*/
-
-/*
-  Terms:
-  
-    1. Interval:  A vertical segment in which no lines cross nor end.
-    2. Scanline:  A physical line, contains 16 subpixels in the horizontal direction
-    3. Slice:     A start stop line pair.
-  
- */
-
-/* Templine logic: 
-   
-   The variable tempflush describes if there is anything in the templine array or not.
-   
-   if tempflush is 0 then the array is clean.
-   if tempflush is 1 then the array contains a partial filled scanline
-   
- */
-
-/* Rendering of a single start stop pair:
-
-?? REWRITE
-   
-   The rendering is split in three parts
-   1. From the first start pixel to the first stop pixel
-   2. Area from the first end pixel to the last start pixel
-   3. Area from the first end pixel to the last start pixel
-
- */
-
-
-void
-i_poly_aa(i_img *im,int l,double *x,double *y,i_color *val) {
-  int i,k;			/* Index variables */
-  int clc;			/* Index of next item on interval linelist */
-  int tx;			/* Coarse x coord within a scanline */
-  pcord miny,maxy;		/* Min and max values of the current slice in the subcord system */
-  pcord minacy,maxacy;		/* Min and max values of the current scanline bounded by the slice
-				   in the subcord system */
-  int cscl;			/* Current scanline */
-  pcord cc;			/* Current vertical centerpoint of interval */
-  int mt1,mt2;
-  int minsx,minex,maxsx,maxex;	/* The horizontal stretches of the lines beloning to the current slice within a scanline */
-  int *templine;		/* Line accumulator */
-
-  struct p_point *pset;		/* List of points in polygon */
-  struct p_line *lset;		/* List of lines in polygon */
-  struct p_slice *tllist;	/* List of slices */
-
-  i_color red,blue,yellow;
-  red.rgb.r=255;
-  red.rgb.g=0;
-  red.rgb.b=0;
-
-  blue.rgb.r=0;
-  blue.rgb.g=0;
-  blue.rgb.b=255;
-
-  yellow.rgb.r=255;
-  yellow.rgb.g=255;
-  yellow.rgb.b=255;
-  
-  if ( (pset=mymalloc(sizeof(struct p_point)*l)) == NULL) { m_fatal(2,"malloc failed\n"); return; }
-  if ( (lset=mymalloc(sizeof(struct p_line)*l)) == NULL) { m_fatal(2,"malloc failed\n"); return; }
-  if ( (tllist=mymalloc(sizeof(struct p_slice)*l)) == NULL) { m_fatal(2,"malloc failed\n"); return; }
-  if ( (templine=mymalloc(sizeof(int)*im->xsize)) == NULL) { m_fatal(2,"malloc failed\n"); return; }
-
-  /* insert the lines into the line list */
-  
-  for(i=0;i<l;i++) {
-    pset[i].n=i;
-    pset[i].x=IMTRUNC(x[i]);
-    pset[i].y=IMTRUNC(y[i]);
-    lset[i].n=i;
-    lset[i].x1=IMTRUNC(x[i]);
-    lset[i].y1=IMTRUNC(y[i]);
-    lset[i].x2=IMTRUNC(x[(i+1)%l]);
-    lset[i].y2=IMTRUNC(y[(i+1)%l]);
-    lset[i].miny=min(lset[i].y1,lset[i].y2);
-    lset[i].maxy=max(lset[i].y1,lset[i].y2);
-  }
-  
-  qsort(pset,l,sizeof(struct p_point),(int(*)(const void *,const void *))p_compy);
-  
-  printf("post point list (sorted in ascending y order)\n");
-  for(i=0;i<l;i++) {
-    printf("%d [ %d ] %d %d\n",i,pset[i].n,pset[i].x,pset[i].y);
-  }
-  
-  printf("line list\n");
-  for(i=0;i<l;i++) {
-    printf("%d [ %d ] (%d , %d) -> (%d , %d) yspan ( %d , %d )\n",i,lset[i].n,lset[i].x1,lset[i].y1,lset[i].x2,lset[i].y2,lset[i].miny,lset[i].maxy);
-  }
-
-  printf("MAIN LOOP\n\n");
-
-  /* Zero templine buffer */
-  /* Templine buffer flushed everytime a scan line ends */
-  for(i=0;i<im->xsize;i++) templine[i]=0;
-  
-
-  /* loop on intervals */
-  for(i=0;i<l-1;i++) {
-    cc=(pset[i].y+pset[i+1].y)/2;
-    printf("current slice is: %d to %d ( cpoint %d )\n",pset[i].y,pset[i+1].y,cc);
-    clc=0;
-
-    /* stuff this in a function ?? */
-
-    /* Check what lines belong to interval */
-    for(k=0;k<l;k++) {
-      printf("checking line: %d [ %d ] (%d , %d) -> (%d, %d) yspan ( %d , %d )",
-	     k,lset[k].n,lset[k].x1,lset[k].y1,lset[k].x2,lset[k].y2,lset[k].miny,lset[k].maxy);
-      if (cc >= lset[k].miny && cc <=  lset[k].maxy) {
-	if (lset[k].miny == lset[k].maxy) printf(" HORIZONTAL - skipped\n");
-	else {
-	  printf(" INSIDE\n"); 
-	  tllist[clc].x=p_eval_aty(&lset[k],cc);
-	  tllist[clc++].n=k;
-	}
-      } else printf(" OUTSIDE\n");
-    }
-    
-    /* 
-       at this point a table of pixels that need special care should
-       be generated from the line list - it should be ordered so that only
-       one needs to be checked - options: rendering to a list then order - or
-       rendering in the right order might be possible to do nicely with the
-       following heuristic:
-       
-       1. Draw leftmost pixel for this line
-       2. If preceeding pixel was occupied check next one else go to 1 again.
-    */
-    
-    printf("lines in current interval:");
-    for(k=0;k<clc;k++) printf("  %d (%.2f)",tllist[k].n,tllist[k].x);
-    printf("\n");
-    
-    /* evaluate the lines in the middle of the slice */
-    
-    printf("Sort lines left to right within interval\n");
-    qsort(tllist,clc,sizeof(struct p_slice),(int(*)(const void *,const void *))p_compx);
-    
-    printf("sorted lines in interval - output:");
-    for(k=0;k<clc;k++) printf(" %d",tllist[k].n);
-    printf("\n");
-    
-    miny=pset[i].y;
-    maxy=pset[i+1].y;
-
-    /* iterate over scanlines */
-    for(cscl=(miny)/16;cscl<=maxy/16;cscl++) {
-      minacy=max(miny,cscl*16);
-      maxacy=min(maxy,cscl*16+15);
-      
-      printf("Scanline bound %d - %d\n",minacy, maxacy);
-
-      /* iterate over line pairs (slices) within interval */
-      for(k=0;k<clc-1;k+=2) {
-
-	mt1=p_eval_aty(&lset[tllist[k].n],minacy);	/* upper corner */
-	mt2=p_eval_aty(&lset[tllist[k].n],maxacy);	/* lower corner */
-	minsx=min(mt1,mt2);
-	minex=max(mt1,mt2);
-	mt1=p_eval_aty(&lset[tllist[k+1].n],minacy);	/* upper corner */
-	mt2=p_eval_aty(&lset[tllist[k+1].n],maxacy);	/* lower corner */
-	maxsx=min(mt1,mt2);
-	maxex=max(mt1,mt2);
-
-	printf("minsx: %d minex: %d\n",minsx,minex);
-	printf("maxsx: %d maxex: %d\n",maxsx,maxex);
-	
-	if (minex/16<maxsx/16) printf("Scan slice is simple!\n");
-	else printf("Scan slice is complicated!\n");
-	
-	if (minsx/16 == minex/16) { /* The line starts and ends in the same pixel */
-	  printf("Low slant start pixel\n");
-	  templine[minsx/16]=(maxacy-minacy+1)*(minex-minsx+1)/2+((minex | 0xF)-minex)*(maxacy-minacy+1);
-	} else {
-	  for(tx=minsx/16;tx<minex/16+1;tx++) {
-	    int minx,maxx,minxy,maxxy;
-	    minx=max(minsx,  tx*16   );
-	    maxx=min(minex,  tx*16+15);
-
-	    if (minx == maxx) {
-	      templine[tx]=(maxacy-minacy+1);
-	    } else {
-	    
-	      minxy=p_eval_atx(&lset[tllist[k].n], minx);
-	      maxxy=p_eval_atx(&lset[tllist[k].n], maxx);
-	      
-	      templine[tx]+=(abs(minxy-maxxy)+1)*(minex-minsx+1)/2; /* The triangle between the points */
-	      if (mt1 < mt2) { /* \ slant */
-		/* ((minex | 0xF)-minex)*(maxacy-minacy+1); FIXME: unfinished */
-		
-
-
-	      } else {
-		templine[tx]+=((minex | 0xF)-minex)*(maxacy-minacy+1);
-	      }
-	      
-	    }
-	  }
-	}
-
-	for(tx=maxsx/16;tx<maxex/16+1;tx++) templine[tx]+=16*(maxacy-minacy+1);
-	
-	/* 	for(tx=minex/16+1;tx<maxsx/16;tx++) 0; */
-	
-	
-	printf("line %d: painting  %d - %d\n",cscl,minex/16+1,maxsx/16);
-	if ( (minacy != cscl*16) || (maxacy != cscl*16+15) ) {
-	  for(tx=minsx/16;tx<maxex/16+1;tx++) {
-	    i_ppix(im,tx,cscl,&yellow);
-	  }
-	}
-	else {
-	  for(tx=minsx/16;tx<minex/16+1;tx++) i_ppix(im,tx,cscl,&red);
-	  for(tx=maxsx/16;tx<maxex/16+1;tx++) i_ppix(im,tx,cscl,&blue);
-	  for(tx=minex/16+1;tx<maxsx/16;tx++) i_ppix(im,tx,cscl,val);
-	}
-
-      } /* Slices */
-    } /* Scanlines */
-  } /* Intervals */
-} /* Function */
-
-
-
-
-
-
-
 /* Flood fill algorithm - based on the Ken Fishkins (pixar) gem in 
    graphics gems I */
 
@@ -925,7 +1078,7 @@ static
 struct stack_element*
 crdata(int left,int right,int dadl,int dadr,int y, int dir) {
   struct stack_element *ste;
-  ste              = mymalloc(sizeof(struct stack_element));
+  ste              = mymalloc(sizeof(struct stack_element)); /* checked 5jul05 tonyc */
   ste->myLx        = left;
   ste->myRx        = right;
   ste->dadLx       = dadl;
@@ -937,33 +1090,46 @@ crdata(int left,int right,int dadl,int dadr,int y, int dir) {
 
 /* i_ccomp compares two colors and gives true if they are the same */
 
+typedef int (*ff_cmpfunc)(i_color const *c1, i_color const *c2, int channels);
+
 static int
-i_ccomp(i_color *val1,i_color *val2,int ch) {
+i_ccomp_normal(i_color const *val1, i_color const *val2, int ch) {
   int i;
-  for(i=0;i<ch;i++) if (val1->channel[i] !=val2->channel[i]) return 0;
+  for(i = 0; i < ch; i++) 
+    if (val1->channel[i] !=val2->channel[i])
+      return 0;
   return 1;
 }
 
+static int
+i_ccomp_border(i_color const *val1, i_color const *val2, int ch) {
+  int i;
+  for(i = 0; i < ch; i++) 
+    if (val1->channel[i] !=val2->channel[i])
+      return 1;
+  return 0;
+}
 
 static int
-i_lspan(i_img *im,int seedx,int seedy,i_color *val) {
+i_lspan(i_img *im, int seedx, int seedy, i_color const *val, ff_cmpfunc cmpfunc) {
   i_color cval;
   while(1) {
     if (seedx-1 < 0) break;
     i_gpix(im,seedx-1,seedy,&cval);
-    if (!i_ccomp(val,&cval,im->channels)) break;
+    if (!cmpfunc(val,&cval,im->channels)) 
+      break;
     seedx--;
   }
   return seedx;
 }
 
 static int
-i_rspan(i_img *im,int seedx,int seedy,i_color *val) {
+i_rspan(i_img *im, int seedx, int seedy, i_color const *val, ff_cmpfunc cmpfunc) {
   i_color cval;
   while(1) {
     if (seedx+1 > im->xsize-1) break;
     i_gpix(im,seedx+1,seedy,&cval);
-    if (!i_ccomp(val,&cval,im->channels)) break;
+    if (!cmpfunc(val,&cval,im->channels)) break;
     seedx++;
   }
   return seedx;
@@ -971,123 +1137,128 @@ i_rspan(i_img *im,int seedx,int seedy,i_color *val) {
 
 /* Macro to create a link and push on to the list */
 
-#define ST_PUSH(left,right,dadl,dadr,y,dir) { struct stack_element *s = crdata(left,right,dadl,dadr,y,dir); llist_push(st,&s); }
+#define ST_PUSH(left,right,dadl,dadr,y,dir) do {                 \
+  struct stack_element *s = crdata(left,right,dadl,dadr,y,dir);  \
+  llist_push(st,&s);                                             \
+} while (0)
 
 /* pops the shadow on TOS into local variables lx,rx,y,direction,dadLx and dadRx */
 /* No overflow check! */
  
-#define ST_POP() { struct stack_element *s; llist_pop(st,&s); lx = s->myLx; rx = s->myRx; dadLx = s->dadLx; dadRx = s->dadRx; y = s->myY; direction= s->myDirection; myfree(s); }
+#define ST_POP() do {         \
+  struct stack_element *s;    \
+  llist_pop(st,&s);           \
+  lx        = s->myLx;        \
+  rx        = s->myRx;        \
+  dadLx     = s->dadLx;       \
+  dadRx     = s->dadRx;       \
+  y         = s->myY;         \
+  direction = s->myDirection; \
+  myfree(s);                  \
+} while (0)
 
-#define ST_STACK(dir,dadLx,dadRx,lx,rx,y) { int pushrx = rx+1; int pushlx = lx-1; ST_PUSH(lx,rx,pushlx,pushrx,y+dir,dir); if (rx > dadRx)                                      ST_PUSH(dadRx+1,rx,pushlx,pushrx,y-dir,-dir); if (lx < dadLx) ST_PUSH(lx,dadLx-1,pushlx,pushrx,y-dir,-dir); }
+#define ST_STACK(dir,dadLx,dadRx,lx,rx,y) do {                    \
+  int pushrx = rx+1;                                              \
+  int pushlx = lx-1;                                              \
+  ST_PUSH(lx,rx,pushlx,pushrx,y+dir,dir);                         \
+  if (rx > dadRx)                                                 \
+    ST_PUSH(dadRx+1,rx,pushlx,pushrx,y-dir,-dir);                 \
+  if (lx < dadLx) ST_PUSH(lx,dadLx-1,pushlx,pushrx,y-dir,-dir);   \
+} while (0)
 
-#define SET(x,y) btm_set(btm,x,y);
+#define SET(x,y) btm_set(btm,x,y)
 
-#define INSIDE(x,y) ((!btm_test(btm,x,y) && ( i_gpix(im,x,y,&cval),i_ccomp(&val,&cval,channels)  ) ))
+/* INSIDE returns true if pixel is correct color and we haven't set it before. */
+#define INSIDE(x,y, seed) ((!btm_test(btm,x,y) && ( i_gpix(im,x,y,&cval),cmpfunc(seed,&cval,channels)  ) ))
 
-void
-i_flood_fill(i_img *im,int seedx,int seedy,i_color *dcol) {
 
-  int lx,rx;
-  int y;
-  int direction;
-  int dadLx,dadRx;
 
-  int wasIn=0;
-  int x=0;
+/* The function that does all the real work */
 
-  /*  int tx,ty; */
+static struct i_bitmap *
+i_flood_fill_low(i_img *im,int seedx,int seedy,
+                 int *bxminp, int *bxmaxp, int *byminp, int *bymaxp,
+		 i_color const *seed, ff_cmpfunc cmpfunc) {
+  int ltx, rtx;
+  int tx = 0;
 
-  int bxmin=seedx,bxmax=seedx,bymin=seedy,bymax=seedy;
+  int bxmin = seedx;
+  int bxmax = seedx;
+  int bymin = seedy;
+  int bymax = seedy;
 
   struct llist *st;
   struct i_bitmap *btm;
 
   int channels,xsize,ysize;
-  i_color cval,val;
+  i_color cval;
 
   channels = im->channels;
   xsize    = im->xsize;
   ysize    = im->ysize;
 
-  btm = btm_new(xsize,ysize);
-  st = llist_new(100,sizeof(struct stack_element*));
-
-  /* Get the reference color */
-  i_gpix(im,seedx,seedy,&val);
+  btm = btm_new(xsize, ysize);
+  st  = llist_new(100, sizeof(struct stack_element*));
 
   /* Find the starting span and fill it */
-  lx = i_lspan(im,seedx,seedy,&val);
-  rx = i_rspan(im,seedx,seedy,&val);
-  
-  /* printf("span: %d %d \n",lx,rx); */
-
-  for(x=lx; x<=rx; x++) SET(x,seedy);
+  ltx = i_lspan(im, seedx, seedy, seed, cmpfunc);
+  rtx = i_rspan(im, seedx, seedy, seed, cmpfunc);
+  for(tx=ltx; tx<=rtx; tx++) SET(tx, seedy);
 
-  ST_PUSH(lx, rx, lx, rx, seedy+1, 1);
-  ST_PUSH(lx, rx, lx, rx, seedy-1,-1);
+  ST_PUSH(ltx, rtx, ltx, rtx, seedy+1,  1);
+  ST_PUSH(ltx, rtx, ltx, rtx, seedy-1, -1);
 
   while(st->count) {
-    ST_POP();
-    
-    if (y<0 || y>ysize-1) continue;
+    /* Stack variables */
+    int lx,rx;
+    int dadLx,dadRx;
+    int y;
+    int direction;
 
-    if (bymin > y) bymin=y; /* in the worst case an extra line */
-    if (bymax < y) bymax=y; 
+    int x;
+    int wasIn=0;
 
-    /*     printf("start of scan - on stack : %d \n",st->count); */
+    ST_POP(); /* sets lx, rx, dadLx, dadRx, y, direction */
 
-    
-    /*     printf("lx=%d rx=%d dadLx=%d dadRx=%d y=%d direction=%d\n",lx,rx,dadLx,dadRx,y,direction); */
-    
-    /*
-    printf(" ");
-    for(tx=0;tx<xsize;tx++) printf("%d",tx%10);
-    printf("\n");
-    for(ty=0;ty<ysize;ty++) {
-      printf("%d",ty%10);
-      for(tx=0;tx<xsize;tx++) printf("%d",!!btm_test(btm,tx,ty));
-      printf("\n");
-    }
 
-    printf("y=%d\n",y);
-    */
+    if (y<0 || y>ysize-1) continue;
+    if (bymin > y) bymin=y; /* in the worst case an extra line */
+    if (bymax < y) bymax=y; 
 
 
-    x=lx+1;
-    if ( (wasIn = INSIDE(lx,y)) ) {
-      SET(lx,y);
+    x = lx+1;
+    if ( lx >= 0 && (wasIn = INSIDE(lx, y, seed)) ) {
+      SET(lx, y);
       lx--;
-      while(INSIDE(lx,y) && lx > 0) {
+      while(INSIDE(lx, y, seed) && lx > 0) {
 	SET(lx,y);
 	lx--;
       }
     }
 
-    if (bxmin > lx) bxmin=lx;
-    
+    if (bxmin > lx) bxmin = lx;
     while(x <= xsize-1) {
       /*  printf("x=%d\n",x); */
       if (wasIn) {
 	
-	if (INSIDE(x,y)) {
+	if (INSIDE(x, y, seed)) {
 	  /* case 1: was inside, am still inside */
 	  SET(x,y);
 	} else {
 	  /* case 2: was inside, am no longer inside: just found the
 	     right edge of a span */
-	  ST_STACK(direction,dadLx,dadRx,lx,(x-1),y);
-
-	  if (bxmax < x) bxmax=x;
+	  ST_STACK(direction, dadLx, dadRx, lx, (x-1), y);
 
+	  if (bxmax < x) bxmax = x;
 	  wasIn=0;
 	}
       } else {
-	if (x>rx) goto EXT;
-	if (INSIDE(x,y)) {
-	  SET(x,y);
+	if (x > rx) goto EXT;
+	if (INSIDE(x, y, seed)) {
+	  SET(x, y);
 	  /* case 3: Wasn't inside, am now: just found the start of a new run */
-	  wasIn=1;
-	    lx=x;
+	  wasIn = 1;
+	    lx = x;
 	} else {
 	  /* case 4: Wasn't inside, still isn't */
 	}
@@ -1097,168 +1268,196 @@ i_flood_fill(i_img *im,int seedx,int seedy,i_color *dcol) {
   EXT: /* out of loop */
     if (wasIn) {
       /* hit an edge of the frame buffer while inside a run */
-      ST_STACK(direction,dadLx,dadRx,lx,(x-1),y);
-      if (bxmax < x) bxmax=x;
+      ST_STACK(direction, dadLx, dadRx, lx, (x-1), y);
+      if (bxmax < x) bxmax = x;
     }
   }
-  
-  /*   printf("lx=%d rx=%d dadLx=%d dadRx=%d y=%d direction=%d\n",lx,rx,dadLx,dadRx,y,direction); 
-       printf("bounding box: [%d,%d] - [%d,%d]\n",bxmin,bymin,bxmax,bymax); */
-
-  for(y=bymin;y<=bymax;y++) for(x=bxmin;x<=bxmax;x++) if (btm_test(btm,x,y)) i_ppix(im,x,y,dcol);
 
-  btm_destroy(btm);
-  mm_log((1, "DESTROY\n"));
   llist_destroy(st);
+
+  *bxminp = bxmin;
+  *bxmaxp = bxmax;
+  *byminp = bymin;
+  *bymaxp = bymax;
+
+  return btm;
 }
 
-static struct i_bitmap *
-i_flood_fill_low(i_img *im,int seedx,int seedy,
-                 int *bxminp, int *bxmaxp, int *byminp, int *bymaxp) {
-  int lx,rx;
-  int y;
-  int direction;
-  int dadLx,dadRx;
+/*
+=item i_flood_fill(im, seedx, seedy, color)
 
-  int wasIn=0;
-  int x=0;
+=category Drawing
+=synopsis i_flood_fill(im, 50, 50, &color);
 
-  /*  int tx,ty; */
+Flood fills the 4-connected region starting from the point (seedx,
+seedy) with I<color>.
 
-  int bxmin=seedx,bxmax=seedx,bymin=seedy,bymax=seedy;
+Returns false if (seedx, seedy) are outside the image.
 
-  struct llist *st;
+=cut
+*/
+
+undef_int
+i_flood_fill(i_img *im, int seedx, int seedy, const i_color *dcol) {
+  int bxmin, bxmax, bymin, bymax;
   struct i_bitmap *btm;
+  int x, y;
+  i_color val;
 
-  int channels,xsize,ysize;
-  i_color cval,val;
+  i_clear_error();
+  if (seedx < 0 || seedx >= im->xsize ||
+      seedy < 0 || seedy >= im->ysize) {
+    i_push_error(0, "i_flood_cfill: Seed pixel outside of image");
+    return 0;
+  }
 
-  channels=im->channels;
-  xsize=im->xsize;
-  ysize=im->ysize;
+  /* Get the reference color */
+  i_gpix(im, seedx, seedy, &val);
 
-  btm=btm_new(xsize,ysize);
-  st=llist_new(100,sizeof(struct stack_element*));
+  btm = i_flood_fill_low(im, seedx, seedy, &bxmin, &bxmax, &bymin, &bymax,
+			 &val, i_ccomp_normal);
 
-  /* Get the reference color */
-  i_gpix(im,seedx,seedy,&val);
+  for(y=bymin;y<=bymax;y++)
+    for(x=bxmin;x<=bxmax;x++)
+      if (btm_test(btm,x,y)) 
+	i_ppix(im,x,y,dcol);
+  btm_destroy(btm);
+  return 1;
+}
 
-  /* Find the starting span and fill it */
-  lx=i_lspan(im,seedx,seedy,&val);
-  rx=i_rspan(im,seedx,seedy,&val);
-  
-  /* printf("span: %d %d \n",lx,rx); */
+/*
+=item i_flood_cfill(im, seedx, seedy, fill)
 
-  for(x=lx;x<=rx;x++) SET(x,seedy);
+=category Drawing
+=synopsis i_flood_cfill(im, 50, 50, fill);
 
-  ST_PUSH(lx,rx,lx,rx,seedy+1,1);
-  ST_PUSH(lx,rx,lx,rx,seedy-1,-1);
+Flood fills the 4-connected region starting from the point (seedx,
+seedy) with I<fill>.
 
-  while(st->count) {
-    ST_POP();
-    
-    if (y<0 || y>ysize-1) continue;
+Returns false if (seedx, seedy) are outside the image.
 
-    if (bymin > y) bymin=y; /* in the worst case an extra line */
-    if (bymax < y) bymax=y; 
+=cut
+*/
 
-    /*     printf("start of scan - on stack : %d \n",st->count); */
+undef_int
+i_flood_cfill(i_img *im, int seedx, int seedy, i_fill_t *fill) {
+  int bxmin, bxmax, bymin, bymax;
+  struct i_bitmap *btm;
+  i_color val;
 
-    
-    /*     printf("lx=%d rx=%d dadLx=%d dadRx=%d y=%d direction=%d\n",lx,rx,dadLx,dadRx,y,direction); */
-    
-    /*
-    printf(" ");
-    for(tx=0;tx<xsize;tx++) printf("%d",tx%10);
-    printf("\n");
-    for(ty=0;ty<ysize;ty++) {
-      printf("%d",ty%10);
-      for(tx=0;tx<xsize;tx++) printf("%d",!!btm_test(btm,tx,ty));
-      printf("\n");
-    }
+  i_clear_error();
+  
+  if (seedx < 0 || seedx >= im->xsize ||
+      seedy < 0 || seedy >= im->ysize) {
+    i_push_error(0, "i_flood_cfill: Seed pixel outside of image");
+    return 0;
+  }
 
-    printf("y=%d\n",y);
-    */
+  /* Get the reference color */
+  i_gpix(im, seedx, seedy, &val);
 
+  btm = i_flood_fill_low(im, seedx, seedy, &bxmin, &bxmax, &bymin, &bymax,
+			 &val, i_ccomp_normal);
 
-    x=lx+1;
-    if ( (wasIn = INSIDE(lx,y)) ) {
-      SET(lx,y);
-      lx--;
-      while(INSIDE(lx,y) && lx > 0) {
-	SET(lx,y);
-	lx--;
-      }
-    }
+  cfill_from_btm(im, fill, btm, bxmin, bxmax, bymin, bymax);
 
-    if (bxmin > lx) bxmin=lx;
-    
-    while(x <= xsize-1) {
-      /*  printf("x=%d\n",x); */
-      if (wasIn) {
-	
-	if (INSIDE(x,y)) {
-	  /* case 1: was inside, am still inside */
-	  SET(x,y);
-	} else {
-	  /* case 2: was inside, am no longer inside: just found the
-	     right edge of a span */
-	  ST_STACK(direction,dadLx,dadRx,lx,(x-1),y);
+  btm_destroy(btm);
+  return 1;
+}
 
-	  if (bxmax < x) bxmax=x;
+/*
+=item i_flood_fill_border(im, seedx, seedy, color, border)
 
-	  wasIn=0;
-	}
-      } else {
-	if (x>rx) goto EXT;
-	if (INSIDE(x,y)) {
-	  SET(x,y);
-	  /* case 3: Wasn't inside, am now: just found the start of a new run */
-	  wasIn=1;
-	    lx=x;
-	} else {
-	  /* case 4: Wasn't inside, still isn't */
-	}
-      }
-      x++;
-    }
-  EXT: /* out of loop */
-    if (wasIn) {
-      /* hit an edge of the frame buffer while inside a run */
-      ST_STACK(direction,dadLx,dadRx,lx,(x-1),y);
-      if (bxmax < x) bxmax=x;
-    }
-  }
-  
-  /*   printf("lx=%d rx=%d dadLx=%d dadRx=%d y=%d direction=%d\n",lx,rx,dadLx,dadRx,y,direction); 
-       printf("bounding box: [%d,%d] - [%d,%d]\n",bxmin,bymin,bxmax,bymax); */
+=category Drawing
+=synopsis i_flood_fill_border(im, 50, 50, &color, &border);
 
-  llist_destroy(st);
+Flood fills the 4-connected region starting from the point (seedx,
+seedy) with I<color>, fill stops when the fill reaches a pixels with
+color I<border>.
 
-  *bxminp = bxmin;
-  *bxmaxp = bxmax;
-  *byminp = bymin;
-  *bymaxp = bymax;
+Returns false if (seedx, seedy) are outside the image.
 
-  return btm;
+=cut
+*/
+
+undef_int
+i_flood_fill_border(i_img *im, int seedx, int seedy, const i_color *dcol,
+		    const i_color *border) {
+  int bxmin, bxmax, bymin, bymax;
+  struct i_bitmap *btm;
+  int x, y;
+
+  i_clear_error();
+  if (seedx < 0 || seedx >= im->xsize ||
+      seedy < 0 || seedy >= im->ysize) {
+    i_push_error(0, "i_flood_cfill: Seed pixel outside of image");
+    return 0;
+  }
+
+  btm = i_flood_fill_low(im, seedx, seedy, &bxmin, &bxmax, &bymin, &bymax,
+			 border, i_ccomp_border);
+
+  for(y=bymin;y<=bymax;y++)
+    for(x=bxmin;x<=bxmax;x++)
+      if (btm_test(btm,x,y)) 
+	i_ppix(im,x,y,dcol);
+  btm_destroy(btm);
+  return 1;
 }
 
-void
-i_flood_cfill(i_img *im, int seedx, int seedy, i_fill_t *fill) {
+/*
+=item i_flood_cfill_border(im, seedx, seedy, fill, border)
+
+=category Drawing
+=synopsis i_flood_cfill_border(im, 50, 50, fill, border);
+
+Flood fills the 4-connected region starting from the point (seedx,
+seedy) with I<fill>, the fill stops when it reaches pixels of color
+I<border>.
+
+Returns false if (seedx, seedy) are outside the image.
+
+=cut
+*/
+
+undef_int
+i_flood_cfill_border(i_img *im, int seedx, int seedy, i_fill_t *fill,
+		     const i_color *border) {
   int bxmin, bxmax, bymin, bymax;
   struct i_bitmap *btm;
+
+  i_clear_error();
+  
+  if (seedx < 0 || seedx >= im->xsize ||
+      seedy < 0 || seedy >= im->ysize) {
+    i_push_error(0, "i_flood_cfill_border: Seed pixel outside of image");
+    return 0;
+  }
+
+  btm = i_flood_fill_low(im, seedx, seedy, &bxmin, &bxmax, &bymin, &bymax,
+			 border, i_ccomp_border);
+
+  cfill_from_btm(im, fill, btm, bxmin, bxmax, bymin, bymax);
+
+  btm_destroy(btm);
+
+  return 1;
+}
+
+static void
+cfill_from_btm(i_img *im, i_fill_t *fill, struct i_bitmap *btm, 
+	       int bxmin, int bxmax, int bymin, int bymax) {
   int x, y;
   int start;
 
-  btm = i_flood_fill_low(im, seedx, seedy, &bxmin, &bxmax, &bymin, &bymax);
-
   if (im->bits == i_8_bits && fill->fill_with_color) {
-    i_color *line = mymalloc(sizeof(i_color) * (bxmax - bxmin));
+    /* bxmax/bxmin are inside the image, hence this won't overflow */
+    i_color *line = mymalloc(sizeof(i_color) * (bxmax - bxmin)); /* checked 5jul05 tonyc */
     i_color *work = NULL;
     if (fill->combine)
-      work = mymalloc(sizeof(i_color) * (bxmax - bxmin));
+      work = mymalloc(sizeof(i_color) * (bxmax - bxmin)); /* checked 5jul05 tonyc */
 
-    for(y=bymin;y<=bymax;y++) {
+    for(y=bymin; y<=bymax; y++) {
       x = bxmin;
       while (x < bxmax) {
         while (x < bxmax && !btm_test(btm, x, y)) {
@@ -1269,10 +1468,16 @@ i_flood_cfill(i_img *im, int seedx, int seedy, i_fill_t *fill) {
           while (x < bxmax && btm_test(btm, x, y)) {
             ++x;
           }
-          if (fill->combine)
+          if (fill->combine) {
             i_glin(im, start, x, y, line);
-          (fill->fill_with_color)(fill, start, y, x-start, im->channels, 
-                                  line, work);
+            (fill->fill_with_color)(fill, start, y, x-start, im->channels, 
+                                    work);
+            (fill->combine)(line, work, im->channels, x-start);
+          }
+          else {
+            (fill->fill_with_color)(fill, start, y, x-start, im->channels, 
+                                    line);
+          }
           i_plin(im, start, x, y, line);
         }
       }
@@ -1282,10 +1487,11 @@ i_flood_cfill(i_img *im, int seedx, int seedy, i_fill_t *fill) {
       myfree(work);
   }
   else {
-    i_fcolor *line = mymalloc(sizeof(i_fcolor) * (bxmax - bxmin));
+    /* bxmax/bxmin are inside the image, hence this won't overflow */
+    i_fcolor *line = mymalloc(sizeof(i_fcolor) * (bxmax - bxmin)); /* checked 5jul05 tonyc */
     i_fcolor *work = NULL;
     if (fill->combinef)
-      work = mymalloc(sizeof(i_fcolor) * (bxmax - bxmin));
+      work = mymalloc(sizeof(i_fcolor) * (bxmax - bxmin)); /* checked 5jul05 tonyc */
     
     for(y=bymin;y<=bymax;y++) {
       x = bxmin;
@@ -1298,10 +1504,16 @@ i_flood_cfill(i_img *im, int seedx, int seedy, i_fill_t *fill) {
           while (x < bxmax && btm_test(btm, x, y)) {
             ++x;
           }
-          if (fill->combinef)
+          if (fill->combinef) {
             i_glinf(im, start, x, y, line);
-          (fill->fill_with_fcolor)(fill, start, y, x-start, im->channels, 
-                                   line, work);
+            (fill->fill_with_fcolor)(fill, start, y, x-start, im->channels, 
+                                    work);
+            (fill->combinef)(line, work, im->channels, x-start);
+          }
+          else {
+            (fill->fill_with_fcolor)(fill, start, y, x-start, im->channels, 
+                                    line);
+          }
           i_plinf(im, start, x, y, line);
         }
       }
@@ -1310,6 +1522,4 @@ i_flood_cfill(i_img *im, int seedx, int seedy, i_fill_t *fill) {
     if (work)
       myfree(work);
   }
-
-  btm_destroy(btm);
 }