[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [43200] trunk/blender/source/blender/ blenkernel/intern/seqeffects.c: Fix #29743: Video sequencer wipe effect bug

[Sergey Sharybin]

Revision: 43200
          http://projects.blender.org/scm/viewvc.php?view=rev&root=bf-blender&revision=43200
Author:   nazgul
Date:     2012-01-06 10:08:46 +0000 (Fri, 06 Jan 2012)
Log Message:
-----------
Fix #29743: Video sequencer wipe effect bug

Blur width used to be calculated quite strange depending on current angle.
Also, it used to be using wrong formula to calculate distance between
current point and boundary line which made blur width almost useless.

Now actual blur width is doesn't depend on angle and use corrected formula
for distance calculation which makes blur width slider behaves more
predictable.

This commit might make old files using wipe+blur be rendered a bit differently,
but don't think it's indeed issue because old behavior was crappy to setup
something useful so don't think this setup was used a lot.

Modified Paths:
--------------
    trunk/blender/source/blender/blenkernel/intern/seqeffects.c

Modified: trunk/blender/source/blender/blenkernel/intern/seqeffects.c
===================================================================
--- trunk/blender/source/blender/blenkernel/intern/seqeffects.c	2012-01-06 05:13:36 UTC (rev 43199)
+++ trunk/blender/source/blender/blenkernel/intern/seqeffects.c	2012-01-06 10:08:46 UTC (rev 43200)
@@ -1574,7 +1574,6 @@
 	int flip;
 	int xo, yo;
 	int width;
-	float invwidth;
 	float pythangle;
 } WipeZone;
 
@@ -1585,33 +1584,25 @@
 	wipezone->xo = xo;
 	wipezone->yo = yo;
 	wipezone->width = (int)(wipe->edgeWidth*((xo+yo)/2.0f));
-	wipezone->pythangle = 1.0f/sqrtf(wipe->angle*wipe->angle + 1.0f);
-
-	if(wipe->wipetype == DO_SINGLE_WIPE)
-		wipezone->invwidth = 1.0f/wipezone->width;
-	else
-		wipezone->invwidth = 1.0f/(0.5f*wipezone->width);
+	wipezone->pythangle = 1.0f/sqrtf(wipezone->angle*wipezone->angle + 1.0f);
 }
 
 // This function calculates the blur band for the wipe effects
-static float in_band(WipeZone *wipezone,float width,float dist,float perc,int side,int dir)
+static float in_band(float width,float dist,int side,int dir)
 {
-	float t1,t2,alpha;
+	float alpha;
 
 	if(width == 0)
 		return (float)side;
-	
+
 	if(width < dist)
-		return side;
-	
-	t1 = dist * wipezone->invwidth;  //percentange of width that is
-	t2 = wipezone->invwidth;  //amount of alpha per % point
-	
+		return (float)side;
+
 	if(side == 1)
-		alpha = (t1*t2*100) + (1-perc); // add point's alpha contrib to current position in wipe
+		alpha = (dist+0.5*width) / (width);
 	else
-		alpha = (1-perc) - (t1*t2*100);
-	
+		alpha = (0.5*width-dist) / (width);
+
 	if(dir == 0)
 		alpha = 1-alpha;
 
@@ -1648,7 +1639,6 @@
 	switch (wipe->wipetype) {
 		case DO_SINGLE_WIPE:
 			width = wipezone->width;
-			hwidth = width*0.5f;
 
 			if(angle == 0.0f) {
 				b1 = posy;
@@ -1669,15 +1659,15 @@
 
 			if(wipe->forward) {
 				if(b1 < b2)
-					output = in_band(wipezone,width,hyp,facf0,1,1);
+					output = in_band(width,hyp,1,1);
 				else
-					output = in_band(wipezone,width,hyp,facf0,0,1);
+					output = in_band(width,hyp,0,1);
 			}
 			else {
 				if(b1 < b2)
-					output = in_band(wipezone,width,hyp,facf0,0,1);
+					output = in_band(width,hyp,0,1);
 				else
-					output = in_band(wipezone,width,hyp,facf0,1,1);
+					output = in_band(width,hyp,1,1);
 			}
 		break;
 
@@ -1700,27 +1690,23 @@
 				b3 = (yo-posy*0.5f) - (-angle)*(xo-posx*0.5f);
 				b2 = y - (-angle)*x;
 
-				hyp = abs(angle*x+y+(-posy*0.5f-angle*posx*0.5f))*wipezone->pythangle;
-				hyp2 = abs(angle*x+y+(-(yo-posy*0.5f)-angle*(xo-posx*0.5f)))*wipezone->pythangle;
+				hyp = fabsf(angle*x+y+(-posy*0.5f-angle*posx*0.5f))*wipezone->pythangle;
+				hyp2 = fabsf(angle*x+y+(-(yo-posy*0.5f)-angle*(xo-posx*0.5f)))*wipezone->pythangle;
 			}
 
-			temp1 = xo*(1-facf0*0.5f)-xo*facf0*0.5f;
-			temp2 = yo*(1-facf0*0.5f)-yo*facf0*0.5f;
-			pointdist = sqrt(temp1*temp1 + temp2*temp2);
+			hwidth= MIN2(hwidth, fabsf(b3-b1)/2.0f);
 
 			if(b2 < b1 && b2 < b3 ){
-				if(hwidth < pointdist)
-					output = in_band(wipezone,hwidth,hyp,facf0,0,1);
+				output = in_band(hwidth,hyp,0,1);
 			} else if(b2 > b1 && b2 > b3 ){
-				if(hwidth < pointdist)
-					output = in_band(wipezone,hwidth,hyp2,facf0,0,1);	
+				output = in_band(hwidth,hyp2,0,1);
 			} else {
 				if(  hyp < hwidth && hyp2 > hwidth )
-					output = in_band(wipezone,hwidth,hyp,facf0,1,1);
+					output = in_band(hwidth,hyp,1,1);
 				else if( hyp > hwidth && hyp2 < hwidth )
-					  output = in_band(wipezone,hwidth,hyp2,facf0,1,1);
+					  output = in_band(hwidth,hyp2,1,1);
 				else
-					  output = in_band(wipezone,hwidth,hyp2,facf0,1,1) * in_band(wipezone,hwidth,hyp,facf0,1,1);
+					  output = in_band(hwidth,hyp2,1,1) * in_band(hwidth,hyp,1,1);
 			}
 			if(!wipe->forward)output = 1-output;
 		break;
@@ -1840,8 +1826,8 @@
 			pointdist = sqrt(temp1*temp1 + temp1*temp1);
 
 			temp2 = sqrt((halfx-x)*(halfx-x) + (halfy-y)*(halfy-y));
-			if(temp2 > pointdist) output = in_band(wipezone,hwidth,fabs(temp2-pointdist),facf0,0,1);
-			else output = in_band(wipezone,hwidth,fabs(temp2-pointdist),facf0,1,1);
+			if(temp2 > pointdist) output = in_band(hwidth,fabs(temp2-pointdist),0,1);
+			else output = in_band(hwidth,fabs(temp2-pointdist),1,1);
 
 			if(!wipe->forward) output = 1-output;