RandR rotations and reflections offset by one pixel

The matrix computation for rotation and reflection resulted in dropping a
row or column of pixels as the offsets used in the matrix computations used
width and height rather than width-1 and height-1.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 14 insertions, 14 deletions

diff --git a/randr/rrtransform.c b/randr/rrtransform.c
index cc18a0662..e5e9438e5 100644
--- a/randr/rrtransform.c
+++ b/randr/rrtransform.c
@@ -185,21 +185,21 @@ RRTransformCompute (int			    x,
 	    break;
 	case RR_Rotate_90:
 	    f_rot_cos = 0;	    f_rot_sin = 1;
-	    f_rot_dx  = height;	    f_rot_dy  = 0;
+	    f_rot_dx  = height-1;   f_rot_dy  = 0;
 	    rot_cos = F ( 0);	    rot_sin = F ( 1);
-	    rot_dx =  F ( height);  rot_dy  = F (0);
+	    rot_dx =  F (height-1); rot_dy  = F (0);
 	    break;
 	case RR_Rotate_180:
 	    f_rot_cos = -1;	    f_rot_sin = 0;
-	    f_rot_dx  = width;	    f_rot_dy  = height;
+	    f_rot_dx  = width - 1;  f_rot_dy  = height - 1;
 	    rot_cos = F (-1);	    rot_sin = F ( 0);
-	    rot_dx  = F (width);   rot_dy  = F ( height);
+	    rot_dx  = F (width-1);  rot_dy  = F ( height-1);
 	    break;
 	case RR_Rotate_270:
 	    f_rot_cos = 0;	    f_rot_sin = -1;
-	    f_rot_dx  = 0;	    f_rot_dy  = width;
+	    f_rot_dx  = 0;	    f_rot_dy  = width-1;
 	    rot_cos = F ( 0);	    rot_sin = F (-1);
-	    rot_dx  = F ( 0);	    rot_dy  = F ( width);
+	    rot_dx  = F ( 0);	    rot_dy  = F ( width-1);
 	    break;
 	}
 	
@@ -222,11 +222,11 @@ RRTransformCompute (int			    x,
 	    f_scale_x = -1;
 	    scale_x = F(-1);
 	    if (rotation & (RR_Rotate_0|RR_Rotate_180)) {
-		f_scale_dx = width;
-		scale_dx = F(width);
+		f_scale_dx = width-1;
+		scale_dx = F(width-1);
 	    } else {
-		f_scale_dx = height;
-		scale_dx = F(height);
+		f_scale_dx = height-1;
+		scale_dx = F(height-1);
 	    }
 	}
 	if (rotation & RR_Reflect_Y)
@@ -234,11 +234,11 @@ RRTransformCompute (int			    x,
 	    f_scale_y = -1;
 	    scale_y = F(-1);
 	    if (rotation & (RR_Rotate_0|RR_Rotate_180)) {
-		f_scale_dy = height;
-		scale_dy = F(height);
+		f_scale_dy = height-1;
+		scale_dy = F(height-1);
 	    } else {
-		f_scale_dy = width;
-		scale_dy = F(width);
+		f_scale_dy = width-1;
+		scale_dy = F(width-1);
 	    }
 	}