View2D could potentially divide stuff by zero, giving bad matrices.

1 files changed, 7 insertions, 3 deletions

diff --git a/source/blender/editors/interface/view2d.c b/source/blender/editors/interface/view2d.c
index a7061ca0fed..74047abb17e 100644
--- a/source/blender/editors/interface/view2d.c
+++ b/source/blender/editors/interface/view2d.c
@@ -1022,15 +1022,19 @@ static void view2d_map_cur_using_mask(View2D *v2d, rctf *curmasked)
 void UI_view2d_view_ortho(View2D *v2d)
 {
 	rctf curmasked;
-	float xofs, yofs;
+	int sizex = BLI_rcti_size_x(&v2d->mask);
+	int sizey = BLI_rcti_size_y(&v2d->mask);
+	float xofs = 0.0f, yofs = 0.0f;
 	
 	/* pixel offsets (-GLA_PIXEL_OFS) are needed to get 1:1 correspondence with pixels for smooth UI drawing,
 	 * but only applied where requested
 	 */
 	/* XXX brecht: instead of zero at least use a tiny offset, otherwise
 	 * pixel rounding is effectively random due to float inaccuracy */
-	xofs = 0.001f * BLI_rctf_size_x(&v2d->cur) / BLI_rcti_size_x(&v2d->mask);
-	yofs = 0.001f * BLI_rctf_size_y(&v2d->cur) / BLI_rcti_size_y(&v2d->mask);
+	if (sizex > 0)
+		xofs = 0.001f * BLI_rctf_size_x(&v2d->cur) / BLI_rcti_size_x(&v2d->mask);
+	if (sizey > 0)
+		yofs = 0.001f * BLI_rctf_size_y(&v2d->cur) / BLI_rcti_size_y(&v2d->mask);
 	
 	/* apply mask-based adjustments to cur rect (due to scrollers), to eliminate scaling artifacts */
 	view2d_map_cur_using_mask(v2d, &curmasked);