[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [20148] branches/blender2.5/blender/source /blender/editors/animation/anim_ipo_utils.c: F-Curve Colouring: Attempt at a new auto-algorithm

[Joshua Leung]

Revision: 20148
          http://projects.blender.org/plugins/scmsvn/viewcvs.php?view=rev&root=bf-blender&revision=20148
Author:   aligorith
Date:     2009-05-11 13:41:08 +0200 (Mon, 11 May 2009)

Log Message:
-----------
F-Curve Colouring: Attempt at a new auto-algorithm

This new algorithm groups F-Curves into groups of 3-4 with similar colours, since triplets of related settings are more likely to be encountered. 

The colours get darker down the list. Blocks of related F-Curves will alternate between being boldly and weakly shaded.

I've left the old method still there but commented out. This new method could still be improved, as some of the colours chosen don't really stand out that well IMO. 

Testing and suggestions welcome as always :)

Modified Paths:
--------------
    branches/blender2.5/blender/source/blender/editors/animation/anim_ipo_utils.c

Modified: branches/blender2.5/blender/source/blender/editors/animation/anim_ipo_utils.c
===================================================================
--- branches/blender2.5/blender/source/blender/editors/animation/anim_ipo_utils.c	2009-05-11 11:31:10 UTC (rev 20147)
+++ branches/blender2.5/blender/source/blender/editors/animation/anim_ipo_utils.c	2009-05-11 11:41:08 UTC (rev 20148)
@@ -148,12 +148,6 @@
 			
 			/* Array Index - only if applicable */
 			if (RNA_property_array_length(prop)) {
-					// XXX the format of these is not final... we don't know how this will go yet
-					// format 1 style
-				//static char *vectoritem[4]= {".X", ".Y", ".Z", ".W"};
-				//static char *quatitem[4]= {".W", ".X", ".Y", ".Z"};
-				//static char *coloritem[4]= {".R", ".G", ".B", ".A"};
-					// format 2 style
 				static char *vectoritem[4]= {"X ", "Y ", "Z ", "W "};
 				static char *quatitem[4]= {"W ", "X ", "Y ", "Z "};
 				static char *coloritem[4]= {"R ", "G ", "B ", "A "};
@@ -181,8 +175,7 @@
 			
 			/* putting this all together into the buffer */
 			// XXX we need to check for invalid names...
-			//BLI_snprintf(name, 128, "%s.%s%s", structname, propname, arrayname);  // format 1
-			BLI_snprintf(name, 128, "%s%s (%s)", arrayname, propname, structname);  // format 2
+			BLI_snprintf(name, 128, "%s%s (%s)", arrayname, propname, structname); 
 			
 			/* free temp name if nameprop is set */
 			if (nameprop)
@@ -197,6 +190,7 @@
 
 /* ------------------------------- Color Codes for F-Curve Channels ---------------------------- */
 
+#if 0
 /* used for FCURVE_COLOR_AUTO_RAINBOW */
 // XXX this still doesn't work too great when there are more than 32 curves (which happens most of the time)
 void ipo_rainbow (int cur, int tot, float *out)
@@ -206,14 +200,57 @@
 	dfac= (float)(1.0/( (float)tot+1.0));
 	
 	/* this calculation makes 2 or 4 different cycles of rainbow colors */
+		// 2 different cycles - for hue
 	if(cur< tot/2) fac= (float)(cur*2.0f*dfac);
 	else fac= (float)((cur-tot/2)*2.0f*dfac +dfac);
+	
+		// third cycle with altered hue
 	if(tot > 32) fac= fac*1.95f;
+		// clamping for excessive ranges
 	if(fac>1.0f) fac-= 1.0f;
 	
+		// saturation adjustments for more visible range
 	if(fac>0.5f && fac<0.8f) sat= 0.5f;
 	else sat= 0.6f;
 	
-	//return hsv_to_cpack(fac, sat, 1.0f);
 	hsv_to_rgb(fac, sat, 1.0f, out, out+1, out+2);
 }
+#endif
+
+/* step between the major distinguishable color bands of the primary colors */
+#define HSV_BANDWIDTH	0.3f
+
+/* testbed for FCURVE_COLOR_AUTO_RAINBOW determination methods */
+//void fcurve_rainbow (unsigned int cur, unsigned int tot, float *out)
+void ipo_rainbow (int cur, int tot, float *out)
+{
+	float hue, val, sat, fac;
+	int grouping;
+	
+	/* we try to divide the colours into groupings of n colors,
+	 * where n is:
+	 *	3 - for 'odd' numbers of curves - there should be a majority of triplets of curves
+	 *	4 - for 'even' numbers of curves - there should be a majority of quartets of curves
+	 * so the base color is simply one of the three primary colors
+	 */
+	grouping= (4 - (tot % 2));
+	hue= HSV_BANDWIDTH * (float)(cur % grouping);
+	
+	/* 'Value' (i.e. darkness) needs to vary so that larger sets of three will be 
+	 * 'darker' (i.e. smaller value), so that they don't look that similar to previous ones.
+	 * However, only a range of 0.3 to 1.0 is really usable to avoid clashing
+	 * with some other stuff 
+	 */
+	fac = ((float)cur / (float)tot) * 0.7f;
+	val = 1.0f - fac;
+	
+	/* the base color can get offset a bit so that the colors aren't so identical */
+	hue += fac * HSV_BANDWIDTH; 
+	if (hue > 1.0f) hue= fmod(hue, 1.0f);
+	
+	/* saturation fluctuates between 0.5 and 1.0 */
+	sat = ((cur / grouping) % 2) ? 0.61f : 0.96f;
+	
+	/* finally, conver this to RGB colors */
+	hsv_to_rgb(hue, sat, val, out, out+1, out+2); 
+}