Fix T41406:

Disallow kernels bigger than 2x2 for blur/sharpen in projective painting
due to performance considerations.

1 files changed, 30 insertions, 24 deletions

diff --git a/source/blender/editors/sculpt_paint/paint_image.c b/source/blender/editors/sculpt_paint/paint_image.c
index e9e1615b27d..0ec813c2631 100644
--- a/source/blender/editors/sculpt_paint/paint_image.c
+++ b/source/blender/editors/sculpt_paint/paint_image.c
@@ -510,19 +510,32 @@ void imapaint_image_update(SpaceImage *sima, Image *image, ImBuf *ibuf, short te
 	}
 }
 
-/* paint blur kernels */
-BlurKernel *paint_new_blur_kernel(Brush *br)
+/* paint blur kernels. Projective painting enforces use of a 2x2 kernel due to lagging */
+BlurKernel *paint_new_blur_kernel(Brush *br, bool proj)
 {
 	int i, j;
 	BlurKernel *kernel = MEM_mallocN(sizeof(BlurKernel), "blur kernel");
-	int pixel_len = br->blur_kernel_radius;
+	float radius;
+	int side;
 	BlurKernelType type = br->blur_mode;
 
-	kernel->side = pixel_len * 2 + 1;
-	kernel->side_squared = kernel->side * kernel->side;
-	kernel->wdata = MEM_mallocN(sizeof(float) * kernel->side_squared, "blur kernel data");
-	kernel->pixel_len = pixel_len;
-
+	if (proj) {
+		radius = 0.5f;
+		
+		side = kernel->side = 2;
+		kernel->side_squared = kernel->side * kernel->side;
+		kernel->wdata = MEM_mallocN(sizeof(float) * kernel->side_squared, "blur kernel data");
+		kernel->pixel_len = radius;
+	}
+	else {
+		radius = br->blur_kernel_radius;
+		
+		side = kernel->side = radius * 2 + 1;
+		kernel->side_squared = kernel->side * kernel->side;
+		kernel->wdata = MEM_mallocN(sizeof(float) * kernel->side_squared, "blur kernel data");
+		kernel->pixel_len = br->blur_kernel_radius;
+	}
+	
 	switch (type) {
 		case KERNEL_BOX:
 			for (i = 0; i < kernel->side_squared; i++)
@@ -531,26 +544,19 @@ BlurKernel *paint_new_blur_kernel(Brush *br)
 
 		case KERNEL_GAUSSIAN:
 		{
-			float standard_dev = pixel_len / 3.0; /* at standard deviation of 3.0 kernel is at about zero */
-			int i_term = pixel_len + 1;
-
+			/* at standard deviation of 3.0 kernel is at about zero */			
+			float standard_dev = radius / 3.0f; 
+			
 			/* make the necessary adjustment to the value for use in the normal distribution formula */
 			standard_dev = standard_dev * standard_dev * 2;
 
-			kernel->wdata[pixel_len + pixel_len * kernel->side] = 1.0;
-			/* fill in all four quadrants at once */
-			for (i = 0; i < i_term; i++) {
-				for (j = 0; j < pixel_len; j++) {
-					float idist = pixel_len - i;
-					float jdist = pixel_len - j;
-
+			for (i = 0; i < side; i++) {
+				for (j = 0; j < side; j++) {
+					float idist = radius - i;
+					float jdist = radius - j;
 					float value = exp((idist * idist + jdist * jdist) / standard_dev);
-
-					kernel->wdata[i + j * kernel->side] =
-					kernel->wdata[(kernel->side - j - 1) + i * kernel->side] =
-					kernel->wdata[(kernel->side - i - 1) + (kernel->side - j - 1) * kernel->side] =
-					kernel->wdata[j + (kernel->side - i - 1) * kernel->side] =
-						value;
+					
+					kernel->wdata[i + j * side] = value;
 				}
 			}