Add quadratic acceleration animation to move for wall

git-svn-id: file:///beryl/trunk@4113 d7aaf104-2d23-0410-ae22-9d23157bf5a3

1 files changed, 21 insertions, 7 deletions

diff --git a/beryl-plugins/src/wall.c b/beryl-plugins/src/wall.c
index 389ecca..535eb37 100644
--- a/beryl-plugins/src/wall.c
+++ b/beryl-plugins/src/wall.c
@@ -1577,15 +1577,29 @@ static void wallPaintTransformedScreen(CompScreen * s,
 
 		int i, j;
 
-		matrixTranslate(&sTransform, ((1 -
-					   left) * ws->destx) * (s->width /
-											 (float)s->outputDev[output].
-											 width),
-					 (-(1 - left) * ws->desty) * (s->height /
-												  (float)s->outputDev[output].
-												  height), 0);
+		// 1.44 isn't a magic number, it can be easily derived from the
+		// following
+		// integral x^2=x^3/3, then solve for x = 1 as we want to translate by 1
+		// total, you get 1.44 and the (tx-1.44) is to translate the parabola
+		// right by 1.44 
+		float tx = (1-left) * 1.4422495;
+		float dx = (tx-1.4422495)*(tx-1.4422495)/2;
+		
+		dx = 1-dx;
+
+		dx*=s->width/(float)s->outputDev[output].width;
+		dx*=ws->destx;
+
+
+		float dy = (tx-1.4422495)*(tx-1.4422495)/2;
+		dy = 1-dy;
 
+		dy *= (s->height)/(float)s->outputDev[output].height;
+		dy*=ws->desty;
 
+		matrixTranslate(&sTransform, dx, -dy, 0);
+		int lbx;
+		int lby;
 
 		for (i = -abs(ws->destx); i < s->hsize; i++)	// TODO: Add a slight bit of intelligence to not be so ineffecient
 		{