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.

8 files changed, 52 insertions, 17 deletions

diff --git a/source/blender/include/BSE_view.h b/source/blender/include/BSE_view.h
index 5943e265f4f..91f360338e9 100644
--- a/source/blender/include/BSE_view.h
+++ b/source/blender/include/BSE_view.h
@@ -77,7 +77,7 @@ void calctrackballvecfirst(struct rcti *area, short *mval, float *vec);
 void calctrackballvec(struct rcti *area, short *mval, float *vec);
 void viewmove(int mode);
 
-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);
 void setwinmatrixview3d(int winx, int winy, struct rctf *rect);
 
 void obmat_to_viewmat(struct Object *ob, short smooth);
diff --git a/source/blender/render/extern/include/RE_pipeline.h b/source/blender/render/extern/include/RE_pipeline.h
index 824050d802f..9abc873172f 100644
--- a/source/blender/render/extern/include/RE_pipeline.h
+++ b/source/blender/render/extern/include/RE_pipeline.h
@@ -158,6 +158,7 @@ void RE_SetDispRect (struct Render *re, rcti *disprect);
 void RE_SetCamera(struct Render *re, struct Object *camera);
 void RE_SetWindow (struct Render *re, rctf *viewplane, float clipsta, float clipend);
 void RE_SetOrtho (struct Render *re, rctf *viewplane, float clipsta, float clipend);
+void RE_SetPixelSize(struct Render *re, float pixsize);
 
 /* option to set viewmatrix before making dbase */
 void RE_SetView (struct Render *re, float mat[][4]);
diff --git a/source/blender/render/intern/source/initrender.c b/source/blender/render/intern/source/initrender.c
index 199212988a7..83c0be6283b 100644
--- a/source/blender/render/intern/source/initrender.c
+++ b/source/blender/render/intern/source/initrender.c
@@ -551,6 +551,11 @@ void RE_SetCamera(Render *re, Object *camera)
 
 }
 
+void RE_SetPixelSize(Render *re, float pixsize)
+{
+	re->viewdx= pixsize;
+	re->viewdy= re->ycor*pixsize;
+}
 
 /* ~~~~~~~~~~~~~~~~ part (tile) calculus ~~~~~~~~~~~~~~~~~~~~~~ */
 
diff --git a/source/blender/render/intern/source/rendercore.c b/source/blender/render/intern/source/rendercore.c
index e9de6d08d74..ba904ff8cee 100644
--- a/source/blender/render/intern/source/rendercore.c
+++ b/source/blender/render/intern/source/rendercore.c
@@ -1126,28 +1126,35 @@ static void addps_sss(void *cb_handle, int facenr, int x, int y, int z)
 	ZBufSSSHandle *handle = cb_handle;
 	RenderPart *pa= handle->pa;
 
-	if (pa->rectall) {
+	/* extra border for filter gives double samples on part edges,
+	   don't use those */
+	if(x<pa->crop || x>=pa->rectx-pa->crop)
+		return;
+	if(y<pa->crop || y>=pa->recty-pa->crop)
+		return;
+	
+	if(pa->rectall) {
 		long *rs= pa->rectall + pa->rectx*y + x;
 
 		addps(&handle->psmlist, rs, facenr, z, 0);
 		handle->totps++;
 	}
-	if (pa->rectz) {
+	if(pa->rectz) {
 		int *rz= pa->rectz + pa->rectx*y + x;
 		int *rp= pa->rectp + pa->rectx*y + x;
 
-		if (z < *rz) {
+		if(z < *rz) {
 			if(*rp == 0)
 				handle->totps++;
 			*rz= z;
 			*rp= facenr;
 		}
 	}
-	if (pa->rectbackz) {
+	if(pa->rectbackz) {
 		int *rz= pa->rectbackz + pa->rectx*y + x;
 		int *rp= pa->rectbackp + pa->rectx*y + x;
 
-		if (z >= *rz) {
+		if(z >= *rz) {
 			if(*rp == 0)
 				handle->totps++;
 			*rz= z;
diff --git a/source/blender/render/intern/source/sss.c b/source/blender/render/intern/source/sss.c
index 2586beb7bb9..a6132c0c062 100644
--- a/source/blender/render/intern/source/sss.c
+++ b/source/blender/render/intern/source/sss.c
@@ -841,7 +841,7 @@ static void sss_create_tree_mat(Render *re, Material *mat)
 	SSSPoints *p;
 	ListBase layers, points;
 	float (*co)[3] = NULL, (*color)[3] = NULL, *area = NULL;
-	int totpoint = 0, osa, osaflag;
+	int totpoint = 0, osa, osaflag, partsdone;
 
 	if(re->test_break())
 		return;
@@ -852,12 +852,14 @@ static void sss_create_tree_mat(Render *re, Material *mat)
 	layers= re->r.layers;
 	osa= re->osa;
 	osaflag= re->r.mode & R_OSA;
+	partsdone= re->i.partsdone;
 
 	re->r.layers.first= re->r.layers.last= NULL;
 	re->osa= 0;
 	re->r.mode &= ~R_OSA;
 	re->sss_points= &points;
 	re->sss_mat= mat;
+	re->i.partsdone= 0;
 
 	RE_TileProcessor(re, 0, 1);
 
@@ -866,6 +868,7 @@ static void sss_create_tree_mat(Render *re, Material *mat)
 	re->r.layers= layers;
 	re->osa= osa;
 	if (osaflag) re->r.mode |= R_OSA;
+	re->i.partsdone= partsdone;
 
 	/* no points? no tree */
 	if(!points.first)
@@ -902,11 +905,15 @@ static void sss_create_tree_mat(Render *re, Material *mat)
 		float ior= mat->sss_ior, cfac= mat->sss_colfac;
 		float *col= mat->sss_col, *radius= mat->sss_radius;
 		float fw= mat->sss_front, bw= mat->sss_back;
+		float error = mat->sss_error;
+		
+		if((R.r.scemode & R_PREVIEWBUTS) && error < 0.5f)
+			error= 0.5f;
 
 		sss->ss[0]= scatter_settings_new(col[0], radius[0], ior, cfac, fw, bw);
 		sss->ss[1]= scatter_settings_new(col[1], radius[1], ior, cfac, fw, bw);
 		sss->ss[2]= scatter_settings_new(col[2], radius[2], ior, cfac, fw, bw);
-		sss->tree= scatter_tree_new(sss->ss, mat->sss_scale, mat->sss_error,
+		sss->tree= scatter_tree_new(sss->ss, mat->sss_scale, error,
 			co, color, area, totpoint);
 
 		MEM_freeN(co);
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;