correction de bugs sur les degrade reliefs

1 files changed, 23 insertions, 8 deletions

diff --git a/generic/Draw.c b/generic/Draw.c
index ce48b3d..cc5378c 100644
--- a/generic/Draw.c
+++ b/generic/Draw.c
@@ -321,27 +321,42 @@ ReliefColorOfSegment(ZnReal		x1,
 		     WidgetInfo		*wi)
 {
   ZnReal	angle, angle_step, origin, position;
-  int		num_colors;
+  int		num_colors, color_index;
   
   num_colors = RELIEF_STEPS*2+1;
-  angle_step = 2*M_PI / num_colors;
+  angle_step = M_PI / (num_colors-1);
   origin = -(DegreesToRadian(wi->light_angle))-(angle_step/2.0);
   if (relief == RELIEF_BEVEL_IN) {
     origin += M_PI;
   }
 
-  angle = (ProjectionToAngle(y1 - y2, x2 - x1) + M_PI - origin);
+  angle = ProjectionToAngle(y1 - y2, x2 - x1) + M_PI - origin;
   while (angle < 0.0) {
     angle += 2*M_PI;
   }
   while (angle > 2*M_PI) {
     angle -= 2*M_PI;
   }	
-  position = (angle/angle_step)*(100/num_colors);
-  /*printf("position %g, angle %g, origin %g\n",
-    position,
-    RadianToDegrees(angle),
-    RadianToDegrees(origin));*/
+
+  color_index = (int) (angle/angle_step);
+  if (color_index > num_colors-1) {
+    color_index = 2*(num_colors-1)-color_index;
+  }
+  if ((color_index < 0) || (color_index >= num_colors)) {
+    printf("Color index out of gradient (should not happen).\n");
+    if (color_index < 0) {
+      color_index = 0;
+    }
+    if (color_index >= num_colors) {
+      color_index = num_colors-1;
+    }
+  }
+  position = 100*color_index/num_colors;
+  /*printf("position %g, angle %g(%g), origin %g\n",
+	 position,
+	 RadianToDegrees(angle),
+	 angle,
+	 RadianToDegrees(origin));*/
 
   return ZnPixel(ZnGetGradientColor(wi->win, gradient, position));
 }