Add a test on the coordinates of a gradient when specified as 2 points. The corner

should be greater than the origin.
Fixed a bug causing a segv when either a gradient is specified either fully on the
right or on the left of the filled object.

1 files changed, 33 insertions, 15 deletions

diff --git a/generic/Color.c b/generic/Color.c
index 8fb7b6a..e79c60e 100644
--- a/generic/Color.c
+++ b/generic/Color.c
@@ -429,15 +429,16 @@ InterpolateGradientColor(Tk_Window      tkwin,
   ZnReal pos1, pos2, ipos, interp_rel_pos, tmp;
   XColor rgb;
 
-  /*printf("interp_pos: %d, min_pos: %d, span: %d\n ", interp_pos, min_pos, span);*/
+  //printf("interp_pos: %d, min_pos: %d, span: %d\n ", interp_pos, min_pos, span);
   pos1 = ((ZnReal)gc1->position-(ZnReal)min_pos)/(ZnReal)span;
   pos2 = ((ZnReal)gc2->position-(ZnReal)min_pos)/(ZnReal)span;
   ipos = ((ZnReal)interp_pos-(ZnReal)min_pos)/(ZnReal)span;
   interp_rel_pos = (ipos-pos1)*100/(pos2-pos1);
 
-  /*printf("pos1: %g, pos2: %g, interp_rel_pos: %g\n", pos1, pos2, interp_rel_pos);*/
+  //printf("pos1: %g, pos2: %g, interp_rel_pos: %g\n", pos1, pos2, interp_rel_pos);
   if (interp_rel_pos < gc1->control) {
     tmp = interp_rel_pos * 100.0 / gc1->control;
+  //printf("rgb : %d, mid rgb : %d\n\n", gc1->rgb, gc1->mid_rgb);
     rgb.red = (unsigned short) (gc1->rgb->red + (gc1->mid_rgb->red - gc1->rgb->red) * tmp / 100.0);
     rgb.green = (unsigned short) (gc1->rgb->green + (gc1->mid_rgb->green - gc1->rgb->green) * tmp / 100.0);
     rgb.blue = (unsigned short) (gc1->rgb->blue + (gc1->mid_rgb->blue - gc1->rgb->blue) * tmp / 100.0);
@@ -494,6 +495,7 @@ InterpolateGradientColor(Tk_Window      tkwin,
       gc_adjust->control = 50;
     }
   }
+  //printf("out of InterpolateGradientColor\n");
 }
 
 
@@ -509,6 +511,7 @@ ReduceGradient(Tk_Window        tkwin,
   int        i, j, first_color, last_color;
   ZnBool     interpolate_first, interpolate_last;
 
+  //printf("In ReduceGradient\n");
   dx = grad->e.x - grad->p.x;
   dy = grad->e.y - grad->p.y;
   len = sqrt(dx*dx+dy*dy);
@@ -558,8 +561,8 @@ ReduceGradient(Tk_Window        tkwin,
     end_in_new = (1-minx)*100/span;
   }
 
-  /*printf("minx: %g, maxx: %g, start%%: %g, end%%: %g\n",
-    minx, maxx, start_in_new, end_in_new);*/
+  //printf("minx: %g, maxx: %g, start%%: %g, end%%: %g\n",
+    //     minx, maxx, start_in_new, end_in_new);
   
   /*
    * Gradient is unchanged
@@ -568,19 +571,21 @@ ReduceGradient(Tk_Window        tkwin,
       (ABS(end_in_new-100.0) < PRECISION_LIMIT)) {
     goto unchanged;
   }
+  //printf("start_in_new: %g, end_in_new: %g\n", start_in_new, end_in_new);
   if ((start_in_new > 100.0) || (end_in_new < 0.0)) {
     grad->num_actual_colors = 1;
     grad->actual_colors = ZnMalloc(sizeof(ZnGradientColor));
+    grad->actual_colors[0].position = 0;
+    grad->actual_colors[0].mid_rgb = NULL;
     if (end_in_new < 0.0) {
-      grad->actual_colors[0].alpha = grad->colors_in[0].alpha;
-      grad->actual_colors[0].rgb = Tk_GetColorByValue(tkwin,
-                                                      grad->colors_in[0].rgb);
+      grad->actual_colors[0].alpha = grad->colors_in[grad->num_colors_in-1].alpha;
+      grad->actual_colors[0].rgb = Tk_GetColorByValue(tkwin, grad->colors_in[grad->num_colors_in-1].rgb);
     }
     else {
-      grad->actual_colors[0].alpha = grad->colors_in[grad->num_colors_in].alpha;
-      grad->actual_colors[0].rgb = Tk_GetColorByValue(tkwin,
-                                                      grad->colors_in[grad->num_colors_in].rgb);
+      grad->actual_colors[0].alpha = grad->colors_in[0].alpha;
+      grad->actual_colors[0].rgb = Tk_GetColorByValue(tkwin, grad->colors_in[0].rgb);
     }
+    return;
   }
 
   grad->num_actual_colors = grad->num_colors_in;
@@ -646,6 +651,7 @@ ReduceGradient(Tk_Window        tkwin,
   grad->actual_colors = ZnMalloc(grad->num_actual_colors*sizeof(ZnGradientColor));
   j = 0;
   if (interpolate_first) {
+    //printf("Interpolate first color, index: %d\n", first_color);
     InterpolateGradientColor(tkwin,
                              &grad->colors_in[first_color-1],
                              &grad->colors_in[first_color],
@@ -681,6 +687,7 @@ ReduceGradient(Tk_Window        tkwin,
   }
 
   if (interpolate_last) {
+    //printf("Interpolate last color\n");
     InterpolateGradientColor(tkwin,
                              &grad->colors_in[last_color],
                              &grad->colors_in[last_color+1],
@@ -698,7 +705,8 @@ ReduceGradient(Tk_Window        tkwin,
     /*printf("adding a color at end\n");*/
   }
   grad->actual_colors[j].position = 100;
-  /*  for (i=0; i<grad->num_actual_colors; i++) printf("control %d: %d\n", i, grad->actual_colors[i].control);*/
+  //for (i=0; i<grad->num_actual_colors; i++) printf("control %d: %d\n", i, grad->actual_colors[i].control);
+  //printf("Out of ReduceGradient\n");
 }
 
 
@@ -816,7 +824,7 @@ ZnGetGradient(Tcl_Interp        *interp,
   int           new, red_range, green_range, blue_range;
   ZnBool        simple;
 
-  /*  printf("ZnGetGradient : %s\n", desc);*/
+  //printf("ZnGetGradient : %s\n", desc);
   if (!desc || !*desc) {
     return NULL;
   }
@@ -920,12 +928,22 @@ ZnGetGradient(Tcl_Interp        *interp,
     }
     else {
       Tcl_AppendResult(interp, "invalid gradient type \"",
-                       desc, "\",", NULL);
+                       desc, "\"", NULL);
       goto grad_err1;
     }
     scan_ptr = next_ptr + 1;
     next_ptr = strchr(scan_ptr, '|');
   }
+  // If the gradient is specified using two points,
+  // test whether the origin point is lower than the corner point.
+  if (num_coords == 4) {
+    if ((coords[2] < coords[0]) || (coords[3] < coords[1])) {
+      Tcl_AppendResult(interp, "Origin point is greater than corner in gradient \"",
+                       desc, "\"", NULL);
+      goto grad_err1;
+    }
+  }
+  
   /*
    * Create the gradient structure.
    */
@@ -1117,8 +1135,8 @@ ZnGetGradient(Tcl_Interp        *interp,
     ReduceGradient(tkwin, grad);
   }
 
-  /*printf("num in: %d, num actual: %d\n", grad->num_colors_in,grad->num_actual_colors);*/
-  /*printf("ZnGetGradient end : %s\n", desc);*/
+  //printf("num in: %d, num actual: %d\n", grad->num_colors_in,grad->num_actual_colors);
+  //printf("ZnGetGradient end : %s\n", desc);
   return grad;
 }