* Adaptive QMC AO feature - "Adapt from speed vectors"

This is a new feature that can make using AO a lot more attractive when rendering 
animations with vector blur. It uses the speed vector info calculated in the 'Vec' 
speed vector pass, in order to reduce AO samples where pixels are moving more 
quickly. There's not much point calculating all those AO samples when the result is 
going to be smeared anyway, so you can save a bit of render time by doing 
a more noisy render in those areas.


You can use this with a new slider in the Adaptive QMC settings 'Adapt Vec'. The 
higher the value, the more aggressively it will reduce samples. 0.0 means no 
reduction, and 1.0 reduces one sample per pixel of average displacement for that 
pixel. 0.25 or so generally gives decent results, but it depends on how fast things 
are moving.

Here's a demo (compare the final blurred result, and render times):
http://mke3.net/blender/devel/raytracing/adapt_speed_off2.jpg
http://mke3.net/blender/devel/raytracing/adapt_speed_on2.jpg

And a less contrived example, a short clip from macouno's 'petunia' bconf animation:
http://mke3.net/blender/devel/raytracing/petunia-adaptvec-noblur-h264.mov
http://mke3.net/blender/devel/raytracing/petunia-adaptvec-blur-h264.mov

4 files changed, 117 insertions, 44 deletions

diff --git a/source/blender/include/butspace.h b/source/blender/include/butspace.h
index 4806b23bd57..fec85c03b77 100644
--- a/source/blender/include/butspace.h
+++ b/source/blender/include/butspace.h
@@ -290,7 +290,7 @@ void curvemap_buttons(struct uiBlock *block, struct CurveMapping *cumap, char la
 #define B_COLZEN		1503
 #define B_WMTEXPASTE	1504
 #define B_WMTEXCOPY		1505
-#define B_AO_DISTANCES	1506
+#define B_AO_FALLOFF	1506
 
 /* *********************** */
 #define B_RENDERBUTS	1700
diff --git a/source/blender/makesdna/DNA_world_types.h b/source/blender/makesdna/DNA_world_types.h
index 769d11ecebe..9e5ec4cdb9a 100644
--- a/source/blender/makesdna/DNA_world_types.h
+++ b/source/blender/makesdna/DNA_world_types.h
@@ -103,8 +103,8 @@ typedef struct World {
 	/* ambient occlusion */
 	float aodist, aodistfac, aoenergy, aobias;
 	short aomode, aosamp, aomix, aocolor;
-	float ao_adapt_thresh;
-	float pad2[3];
+	float ao_adapt_thresh, ao_adapt_speed_fac;
+	float pad2[2];
 	short ao_samp_method;
 	short pad1[3];
 	
diff --git a/source/blender/render/intern/source/rayshade.c b/source/blender/render/intern/source/rayshade.c
index 560d2151e42..3a859b083ed 100644
--- a/source/blender/render/intern/source/rayshade.c
+++ b/source/blender/render/intern/source/rayshade.c
@@ -806,6 +806,23 @@ static void QMC_sampleHemi(float *vec, QMCSampler *qsa, int thread, int num)
 	vec[2] = 1.f - s[1]*s[1];
 }
 
+/* cosine weighted hemisphere sampling */
+static void QMC_sampleHemiCosine(float *vec, QMCSampler *qsa, int thread, int num)
+{
+	double s[2];
+	float phi, sqr;
+	
+	QMC_getSample(s, qsa, thread, num);
+	
+	phi = s[0]*2.f*M_PI;	
+	sqr = s[1]*sqrt(2-s[1]*s[1]);
+
+	vec[0] = cos(phi)*sqr;
+	vec[1] = sin(phi)*sqr;
+	vec[2] = 1.f - s[1]*s[1];
+
+}
+
 /* called from convertBlenderScene.c */
 /* samples don't change per pixel, so build the samples in advance for efficiency */
 void init_lamp_hammersley(LampRen *lar)
@@ -861,6 +878,20 @@ static int adaptive_sample_contrast_val(int samples, float prev, float val, floa
 		return 0;
 }
 
+static float get_avg_speed(ShadeInput *shi)
+{
+	float pre_x, pre_y, post_x, post_y, speedavg;
+	
+	pre_x = (shi->winspeed[0] == PASS_VECTOR_MAX)?0.0:shi->winspeed[0];
+	pre_y = (shi->winspeed[1] == PASS_VECTOR_MAX)?0.0:shi->winspeed[1];
+	post_x = (shi->winspeed[2] == PASS_VECTOR_MAX)?0.0:shi->winspeed[2];
+	post_y = (shi->winspeed[3] == PASS_VECTOR_MAX)?0.0:shi->winspeed[3];
+	
+	speedavg = (sqrt(pre_x*pre_x + pre_y*pre_y) + sqrt(post_x*post_x + post_y*post_y)) / 2.0;
+	
+	return speedavg;
+}
+
 /* ***************** main calls ************** */
 
 
@@ -1407,6 +1438,7 @@ void ray_ao_qmc(ShadeInput *shi, float *shadfac)
 	float maxdist = R.wrld.aodist;
 	float fac=0.0f, prev=0.0f;
 	float adapt_thresh = G.scene->world->ao_adapt_thresh;
+	float adapt_speed_fac = G.scene->world->ao_adapt_speed_fac;
 	float bias = G.scene->world->aobias;
 	
 	int samples=0;
@@ -1447,9 +1479,16 @@ void ray_ao_qmc(ShadeInput *shi, float *shadfac)
 	VecOrthoBasisf(nrm, up, side);
 	
 	/* sampling init */
-	if (R.wrld.ao_samp_method==WO_AOSAMP_HALTON) 
+	if (R.wrld.ao_samp_method==WO_AOSAMP_HALTON) {
+		float speedfac;
+		
+		speedfac = get_avg_speed(shi) * adapt_speed_fac;
+		CLAMP(speedfac, 1.0, 1000.0);
+		max_samples /= speedfac;
+		if (max_samples < 5) max_samples = 5;
+		
 		qsa = QMC_initSampler(SAMP_TYPE_HALTON, max_samples);
-	else if (R.wrld.ao_samp_method==WO_AOSAMP_HAMMERSLEY)
+	} else if (R.wrld.ao_samp_method==WO_AOSAMP_HAMMERSLEY)
 		qsa = R.qsa;
 
 	QMC_initPixel(qsa, shi->thread);
@@ -1458,7 +1497,7 @@ void ray_ao_qmc(ShadeInput *shi, float *shadfac)
 
 		/* sampling, returns quasi-random vector in unit hemisphere */
 		QMC_sampleHemi(samp3d, qsa, shi->thread, samples);
-		
+
 		dir[0] = (samp3d[0]*up[0] + samp3d[1]*side[0] + samp3d[2]*nrm[0]);
 		dir[1] = (samp3d[0]*up[1] + samp3d[1]*side[1] + samp3d[2]*nrm[1]);
 		dir[2] = (samp3d[0]*up[2] + samp3d[1]*side[2] + samp3d[2]*nrm[2]);
diff --git a/source/blender/src/buttons_shading.c b/source/blender/src/buttons_shading.c
index 56c8d60bf5b..67ccf78c5f6 100644
--- a/source/blender/src/buttons_shading.c
+++ b/source/blender/src/buttons_shading.c
@@ -1923,8 +1923,8 @@ void do_worldbuts(unsigned short event)
 			scrarea_queue_winredraw(curarea);
 		}
 		break;
-	case B_AO_DISTANCES:
-		/* distances option only supports plain */
+	case B_AO_FALLOFF:
+		/* falloff distances option only supports plain */
 		wrld= G.buts->lockpoin;
 		if(wrld)
 			wrld->aocolor= WO_AOPLAIN;
@@ -2124,54 +2124,88 @@ static void world_panel_mistaph(World *wrld)
 static void world_panel_amb_occ(World *wrld)
 {
 	uiBlock *block;
+	short yco=PANEL_YMAX;
 	
 	block= uiNewBlock(&curarea->uiblocks, "world_panel_amb_oc", UI_EMBOSS, UI_HELV, curarea->win);
 	uiNewPanelTabbed("Mist / Stars / Physics", "World");
-	if(uiNewPanel(curarea, block, "Amb Occ", "World", 320, 0, 318, 204)==0) return;
+	if(uiNewPanel(curarea, block, "Amb Occ", "World", PANELX, PANELY, PANELW, PANELH)==0) return;
 
 	uiBlockSetCol(block, TH_BUT_SETTING1);
-	uiDefButBitS(block, TOG, WO_AMB_OCC, B_REDR,	"Ambient Occlusion",10,150,300,19, &wrld->mode, 0, 0, 0, 0, "Toggles ambient occlusion (soft shadows)");
+	uiDefButBitS(block, TOG, WO_AMB_OCC, B_REDR, "Ambient Occlusion",
+		X2CLM1, yco-=BUTH, BUTW1, BUTH, &wrld->mode, 0, 0, 0, 0, "Toggles ambient occlusion (soft shadows)");
 	uiBlockSetCol(block, TH_AUTO);
+	
+	if(!(wrld->mode & WO_AMB_OCC)) return;
+	
+	yco -= YSPACE;
 
-	if(wrld->mode & WO_AMB_OCC) {
-
-		/* aolight: samples */
-		uiDefButS(block, MENU, B_REDR, "Constant QMC %x2|Adaptive QMC %x1|Constant Jittered %x0",
-				10, 120, 145, 19, &wrld->ao_samp_method, 0, 0, 0, 0, "Method for generating shadow samples: Constant QMC: best quality, Adaptive QMC: fast in high contrast areas");
-		uiDefButS(block, NUM, B_REDR, "Samples:",
-				165, 120, 145, 19, &wrld->aosamp, 1.0, 32.0, 100, 0, "Sets the number of samples used for AO  (actual number: squared)");
-		
-		if (wrld->ao_samp_method == WO_AOSAMP_HALTON) {
-			uiDefButF(block, NUM, B_REDR, "Threshold:",
-				10, 95, 145, 19, &wrld->ao_adapt_thresh, 0.0, 1.0, 100, 0, "Samples below this threshold will be considered fully shadowed/unshadowed and skipped");
-		}
-		uiDefButF(block, NUM, B_REDR, "Dist:",
-			165, 95, 145, 19, &wrld->aodist, 0.001, 5000.0, 100, 0, "Sets length of AO rays, defines how far away other faces give occlusion effect");
+	uiDefButS(block, NUM, B_REDR, "Samples:",
+		X2CLM1, yco-=BUTH, BUTW2, BUTH, &wrld->aosamp, 1.0, 32.0, 100, 0, "Sets the number of samples used for AO  (actual number: squared)");
+	
+	yco -= YSPACE;
+	
+	uiDefButF(block, NUM, B_REDR, "Max Dist:",
+		X2CLM1, yco-=BUTH, BUTW2, BUTH, &wrld->aodist, 0.001, 5000.0, 100, 0, "Sets length of AO rays, defines how far away other faces give occlusion effect");
 
+	yco -= YSPACE;
+	
+	uiBlockBeginAlign(block);
+	uiDefButBitS(block, TOG, WO_AODIST, B_AO_FALLOFF, "Use Falloff",
+		X2CLM1, yco-=BUTH, BUTW2, BUTH, &wrld->aomode, 0, 0, 0, 0, "When enabled, distances to objects will be used to attenuate shadows. Only for Plain AO.");
+	if (wrld->aomode & WO_AODIST)
+		uiDefButF(block, NUM, B_REDR, "Strength:",
+			X2CLM1, yco-=BUTH, BUTW2, BUTH, &wrld->aodistfac, 0.00001, 10.0, 100, 0, "Distance attenuation factor, the higher, the 'shorter' the shadows");
+	uiBlockEndAlign(block);
+	
+	/* column 2 */
+	yco = PANEL_YMAX - BUTH - YSPACE;
+	
+	uiDefButS(block, MENU, B_REDR, "Constant QMC %x2|Adaptive QMC %x1|Constant Jittered %x0",
+		X2CLM2, yco-=BUTH, BUTW2, BUTH, &wrld->ao_samp_method, 0, 0, 0, 0, "Method for generating shadow samples: Constant QMC: best quality, Adaptive QMC: fast in high contrast areas");
+	
+	yco -= YSPACE;
+	
+	if (wrld->ao_samp_method == WO_AOSAMP_HALTON) {	
 		uiBlockBeginAlign(block);
-		uiDefButBitS(block, TOG, WO_AODIST, B_AO_DISTANCES, "Use Distances", 10, 70, 150, 19, &wrld->aomode, 0, 0, 0, 0, "When enabled, distances to objects will be used to attenuate shadows. Only for Plain AO.");
-		/* distance attenuation factor */
-		if (wrld->aomode & WO_AODIST)
-			uiDefButF(block, NUM, B_REDR, "DistF:", 160, 70, 150, 19, &wrld->aodistfac, 0.00001, 10.0, 100, 0, "Distance factor, the higher, the 'shorter' the shadows");
+		uiDefButF(block, NUM, B_REDR, "Threshold:",
+			X2CLM2, yco-=BUTH, BUTW2, BUTH, &wrld->ao_adapt_thresh, 0.0, 1.0, 100, 0, "Samples below this threshold will be considered fully shadowed/unshadowed and skipped");
+		uiDefButF(block, NUMSLI, B_REDR, "Adapt Vec:",
+			X2CLM2, yco-=BUTH, BUTW2, BUTH, &wrld->ao_adapt_speed_fac, 0.0, 1.0, 100, 0, "Use the speed vector pass to reduce AO samples in fast moving pixels. The higher the value, the more aggressive the sample reduction. Requires Vec pass enabled.");
+		uiBlockEndAlign(block);
+	} else if (wrld->ao_samp_method == WO_AOSAMP_CONSTANT) {
+		uiDefButF(block, NUMSLI, B_REDR, "Bias:",
+			X2CLM2, yco-=BUTH, BUTW2, BUTH, &wrld->aobias, 0.0, 0.5, 10, 0, "Sets bias to prevent smoothed faces to show banding (in radians)");
+	}
 
-		/* result mix modes */
-		uiBlockBeginAlign(block);
-		uiDefButS(block, ROW, B_REDR, "Add", 10, 45, 100, 20, &wrld->aomix, 1.0, (float)WO_AOADD, 0, 0, "adds light/shadows");
-		uiDefButS(block, ROW, B_REDR, "Sub", 110, 45, 100, 20, &wrld->aomix, 1.0, (float)WO_AOSUB, 0, 0, "subtracts light/shadows (needs at least one normal light to make anything visible)");
-		uiDefButS(block, ROW, B_REDR, "Both", 210, 45, 100, 20, &wrld->aomix, 1.0, (float)WO_AOADDSUB, 0, 0, "both lightens & darkens");
 
-		/* color treatment */
-		uiBlockBeginAlign(block);
-		uiDefButS(block, ROW, B_REDR, "Plain", 10, 25, 100, 20, &wrld->aocolor, 2.0, (float)WO_AOPLAIN, 0, 0, "Plain diffuse energy (white)");
-		uiDefButS(block, ROW, B_REDR, "Sky Color", 110, 25, 100, 20, &wrld->aocolor, 2.0, (float)WO_AOSKYCOL, 0, 0, "Use horizon and zenith color for diffuse energy");
-		uiDefButS(block, ROW, B_REDR, "Sky Texture", 210, 25, 100, 20, &wrld->aocolor, 2.0, (float)WO_AOSKYTEX, 0, 0, "Does full Sky texture render for diffuse energy");
-		
-		uiBlockBeginAlign(block);
-		uiDefButF(block, NUMSLI, B_REDR, "Energy:", 10, 0, 150, 19, &wrld->aoenergy, 0.01, 3.0, 100, 0, "Sets global energy scale for AO");
-		if (wrld->ao_samp_method == WO_AOSAMP_CONSTANT)
-			uiDefButF(block, NUMSLI, B_REDR, "Bias:", 160, 0, 150, 19, &wrld->aobias, 0.0, 0.5, 10, 0, "Sets bias to prevent smoothed faces to show banding (in radians)");
-	}
+	yco = PANEL_YMAX - (5*BUTH+4*YSPACE);
+
+	/* result mix modes */
+	uiBlockBeginAlign(block);
+	uiDefButS(block, ROW, B_REDR, "Add",
+		X3CLM1, yco-=BUTH, BUTW3, BUTH, &wrld->aomix, 1.0, (float)WO_AOADD, 0, 0, "adds light/shadows");
+	uiDefButS(block, ROW, B_REDR, "Sub",
+		X3CLM2, yco, BUTW3, BUTH, &wrld->aomix, 1.0, (float)WO_AOSUB, 0, 0, "subtracts light/shadows (needs at least one normal light to make anything visible)");
+	uiDefButS(block, ROW, B_REDR, "Both",
+		X3CLM3, yco, BUTW3, BUTH, &wrld->aomix, 1.0, (float)WO_AOADDSUB, 0, 0, "both lightens & darkens");
+
+	yco -= YSPACE;
 
+	/* color treatment */
+	uiBlockBeginAlign(block);
+	uiDefButS(block, ROW, B_REDR, "Plain",
+		X3CLM1, yco-=BUTH, BUTW3, BUTH, &wrld->aocolor, 2.0, (float)WO_AOPLAIN, 0, 0, "Plain diffuse energy (white)");
+	uiDefButS(block, ROW, B_REDR, "Sky Color", 
+		X3CLM2, yco, BUTW3, BUTH, &wrld->aocolor, 2.0, (float)WO_AOSKYCOL, 0, 0, "Use horizon and zenith color for diffuse energy");
+	uiDefButS(block, ROW, B_REDR, "Sky Texture", 
+		X3CLM3, yco, BUTW3, BUTH, &wrld->aocolor, 2.0, (float)WO_AOSKYTEX, 0, 0, "Does full Sky texture render for diffuse energy");
+	uiBlockEndAlign(block);
+	
+	yco -= YSPACE;
+	
+	uiDefButF(block, NUMSLI, B_REDR, "Energy:",
+		X2CLM1, yco-=BUTH, BUTW2, BUTH, &wrld->aoenergy, 0.01, 3.0, 100, 0, "Sets global energy scale for AO");
+	
 }
 
 static void world_panel_world(World *wrld)