SSS fixes:

- Radius R, G, B sliders had too small number increase on clicking.
- Preview render now renders with higher SSS error setting to speed it up a
  bit.
- bug #6664: 3d preview render had artifacts. re->viewdx/dy wasn't set then,
  which is needed to estimate the area of each point. Have set this now, not
  in the nicest way, there is some bit duplicated code, but I don't want to
  refactor existing code with the chance of breaking it at this point.
- bug #6665: grid like artifacts with parts rendering. The two extra pixels
  around parts used for filtering were used as well, leading to double points.

3 files changed, 24 insertions, 9 deletions

diff --git a/source/blender/src/buttons_shading.c b/source/blender/src/buttons_shading.c
index 35277030857..0d1a783ddea 100644
--- a/source/blender/src/buttons_shading.c
+++ b/source/blender/src/buttons_shading.c
@@ -3326,15 +3326,15 @@ static void material_panel_sss(Material *ma)
 	uiDefButF(block, NUM, B_MATPRV, "Scale:", 10,150,145,20,
 			  &ma->sss_scale, 0.001, 1000, 1, 3, "Object scale");
 	bt=uiDefButF(block, NUM, B_MATPRV, "Radius R", 10,130,145,20,
-			  &ma->sss_radius[0], 0.00001, 10000, 0, 0,
+			  &ma->sss_radius[0], 0.0001, 10000, 1, 3,
 			  "Mean red scattering path length");
 	uiButSetFunc(bt, material_sss_custom_set_cb, ma, NULL);
 	bt=uiDefButF(block, NUM, B_MATPRV, "Radius G", 10,110,145,20,
-			  &ma->sss_radius[1], 0.00001, 10000, 0, 0,
+			  &ma->sss_radius[1], 0.0001, 10000, 1, 3,
 			  "Mean green scattering path length");
 	uiButSetFunc(bt, material_sss_custom_set_cb, ma, NULL);
 	bt=uiDefButF(block, NUM, B_MATPRV, "Radius B", 10,90,145,20,
-			  &ma->sss_radius[2], 0.00001, 10000, 0, 0,
+			  &ma->sss_radius[2], 0.0001, 10000, 1, 3,
 			  "Mean blue scattering path length");
 	uiButSetFunc(bt, material_sss_custom_set_cb, ma, NULL);
 	uiBlockEndAlign(block);
diff --git a/source/blender/src/previewrender.c b/source/blender/src/previewrender.c
index 1526de1b74d..fb9ea19742f 100644
--- a/source/blender/src/previewrender.c
+++ b/source/blender/src/previewrender.c
@@ -673,7 +673,7 @@ void BIF_view3d_previewrender_free(View3D *v3d)
 }
 
 /* returns 1 if OK, do not call while in panel space!  */
-static int view3d_previewrender_get_rects(ScrArea *sa, rctf *viewplane, RenderInfo *ri, float *clipsta, float *clipend, int *ortho)
+static int view3d_previewrender_get_rects(ScrArea *sa, rctf *viewplane, RenderInfo *ri, float *clipsta, float *clipend, int *ortho, float *pixsize)
 {
 	int rectx, recty;
 	uiBlock *block;
@@ -690,7 +690,7 @@ static int view3d_previewrender_get_rects(ScrArea *sa, rctf *viewplane, RenderIn
 	/* correction for gla draw */
 	BLI_translate_rcti(&ri->disprect, -sa->winrct.xmin, -sa->winrct.ymin);
 	
-	*ortho= get_view3d_viewplane(sa->winx, sa->winy, viewplane, clipsta, clipend);
+	*ortho= get_view3d_viewplane(sa->winx, sa->winy, viewplane, clipsta, clipend, pixsize);
 
 	rectx= ri->disprect.xmax - ri->disprect.xmin;
 	recty= ri->disprect.ymax - ri->disprect.ymin;
@@ -732,7 +732,7 @@ void BIF_view3d_previewrender(ScrArea *sa)
 	RenderStats *rstats;
 	RenderData rdata;
 	rctf viewplane;
-	float clipsta, clipend;
+	float clipsta, clipend, pixsize;
 	int orth;
 	
 	/* first get the render info right */
@@ -742,7 +742,7 @@ void BIF_view3d_previewrender(ScrArea *sa)
 	}
 	ri= v3d->ri;
 	
-	if(0==view3d_previewrender_get_rects(sa, &viewplane, ri, &clipsta, &clipend, &orth))
+	if(0==view3d_previewrender_get_rects(sa, &viewplane, ri, &clipsta, &clipend, &orth, &pixsize))
 		return;
 	
 	/* render is finished, so return */
@@ -779,6 +779,7 @@ void BIF_view3d_previewrender(ScrArea *sa)
 			RE_SetOrtho(re, &viewplane, clipsta, clipend);
 		else
 			RE_SetWindow(re, &viewplane, clipsta, clipend);
+		RE_SetPixelSize(re, pixsize);
 		
 		/* until here are no escapes */
 		ri->status |= PR_DISPRECT;
@@ -798,6 +799,7 @@ void BIF_view3d_previewrender(ScrArea *sa)
 				RE_SetOrtho(ri->re, &viewplane, clipsta, clipend);
 			else
 				RE_SetWindow(ri->re, &viewplane, clipsta, clipend);
+			RE_SetPixelSize(re, pixsize);
 			ri->status |= PR_DISPRECT;
 			ri->curtile= 0;
 			//printf("disprect update\n");
diff --git a/source/blender/src/view.c b/source/blender/src/view.c
index d5cfef5d590..c501dbb8f73 100644
--- a/source/blender/src/view.c
+++ b/source/blender/src/view.c
@@ -825,7 +825,7 @@ void object_view_settings(Object *ob, float *lens, float *clipsta, float *clipen
 }
 
 
-int get_view3d_viewplane(int winxi, int winyi, rctf *viewplane, float *clipsta, float *clipend)
+int get_view3d_viewplane(int winxi, int winyi, rctf *viewplane, float *clipsta, float *clipend, float *pixsize)
 {
 	Camera *cam=NULL;
 	float lens, fac, x1, y1, x2, y2;
@@ -922,6 +922,19 @@ int get_view3d_viewplane(int winxi, int winyi, rctf *viewplane, float *clipsta,
 			y2+= dy;
 		}
 	}
+
+	if(pixsize) {
+		float viewfac;
+
+		if(orth) {
+			viewfac= (winx >= winy)? winx: winy;
+			*pixsize= 1.0f/viewfac;
+		}
+		else {
+			viewfac= (((winx >= winy)? winx: winy)*lens)/32.0;
+			*pixsize= *clipsta/viewfac;
+		}
+	}
 	
 	viewplane->xmin= x1;
 	viewplane->ymin= y1;
@@ -938,7 +951,7 @@ void setwinmatrixview3d(int winx, int winy, rctf *rect)		/* rect: for picking */
 	float clipsta, clipend, x1, y1, x2, y2;
 	int orth;
 	
-	orth= get_view3d_viewplane(winx, winy, &viewplane, &clipsta, &clipend);
+	orth= get_view3d_viewplane(winx, winy, &viewplane, &clipsta, &clipend, NULL);
 //	printf("%d %d %f %f %f %f %f %f\n", winx, winy, viewplane.xmin, viewplane.ymin, viewplane.xmax, viewplane.ymax, clipsta, clipend);
 	x1= viewplane.xmin;
 	y1= viewplane.ymin;