Attempted fix for bug #8349: QMC raytracing being very slow on some

computers, probably due to slow multithreaded malloc. Now each render
thread keeps a list of qmc samplers that it fills as needed while
rendering (since it is hard to predict the actual amount needed in
advance due to ray recursion).

4 files changed, 77 insertions, 47 deletions

diff --git a/source/blender/render/intern/include/render_types.h b/source/blender/render/intern/include/render_types.h
index 22fb2e70d87..c2d2ea96745 100644
--- a/source/blender/render/intern/include/render_types.h
+++ b/source/blender/render/intern/include/render_types.h
@@ -64,8 +64,10 @@ typedef struct SampleTables
 
 typedef struct QMCSampler
 {
+	struct QMCSampler *next, *prev;
 	int type;
 	int tot;
+	int used;
 	double *samp2d;
 	double offs[BLENDER_MAX_THREADS][2];
 } QMCSampler;
@@ -150,7 +152,7 @@ struct Render
 	/* samples */
 	SampleTables *samples;
 	float jit[32][2];
-	QMCSampler *qsa;
+	ListBase *qmcsamplers;
 	
 	/* shadow counter, detect shadow-reuse for shaders */
 	int shadowsamplenr[BLENDER_MAX_THREADS];
@@ -455,7 +457,6 @@ typedef struct LampRen {
 
 	struct ShadBuf *shb;
 	float *jitter;
-	QMCSampler *qsa;
 	
 	float imat[3][3];
 	float spottexfac;
diff --git a/source/blender/render/intern/include/rendercore.h b/source/blender/render/intern/include/rendercore.h
index cdc348279e5..0edca1a15a9 100644
--- a/source/blender/render/intern/include/rendercore.h
+++ b/source/blender/render/intern/include/rendercore.h
@@ -104,9 +104,7 @@ extern void ray_trace(ShadeInput *, ShadeResult *);
 extern void ray_ao(ShadeInput *, float *);
 extern void init_jitter_plane(LampRen *lar);
 extern void init_ao_sphere(struct World *wrld);
-extern void init_lamp_hammersley(LampRen *lar);
-extern void free_lamp_qmcsampler(LampRen *lar);
-extern void init_render_hammersley(Render *re);
+extern void init_render_qmcsampler(Render *re);
 extern void free_render_qmcsampler(Render *re);
 
 #endif /* RENDER_EXT_H */
diff --git a/source/blender/render/intern/source/convertblender.c b/source/blender/render/intern/source/convertblender.c
index 0f741e8e358..c2bb6229131 100644
--- a/source/blender/render/intern/source/convertblender.c
+++ b/source/blender/render/intern/source/convertblender.c
@@ -3684,9 +3684,6 @@ static GroupObject *add_render_lamp(Render *re, Object *ob)
 
 		if(re->r.mode & R_SHADOW) {
 			
-			if ((lar->mode & LA_SHAD_RAY) && (lar->ray_samp_method == LA_SAMP_HAMMERSLEY)) {
-				init_lamp_hammersley(lar);
-			}
 			if(la->type==LA_AREA && (lar->mode & LA_SHAD_RAY) && (lar->ray_samp_method == LA_SAMP_CONSTANT)) {
 				init_jitter_plane(lar);
 			}
@@ -4372,7 +4369,6 @@ void RE_Database_Free(Render *re)
 		freeshadowbuf(lar);
 		if(lar->jitter) MEM_freeN(lar->jitter);
 		if(lar->shadsamp) MEM_freeN(lar->shadsamp);
-		if(lar->qsa) free_lamp_qmcsampler(lar);
 		curvemapping_free(lar->curfalloff);
 	}
 	
@@ -4410,8 +4406,7 @@ void RE_Database_Free(Render *re)
 		re->wrld.aotables= NULL;
 		re->scene->world->aotables= NULL;
 	}
-	if((re->r.mode & R_RAYTRACE) && (re->wrld.mode & WO_AMB_OCC) &&
-	    (re->wrld.ao_samp_method == WO_AOSAMP_HAMMERSLEY) && (re->qsa))
+	if(re->r.mode & R_RAYTRACE)
 		free_render_qmcsampler(re);
 	
 	if(re->r.mode & R_RAYTRACE) freeraytree(re);
@@ -4786,11 +4781,12 @@ void RE_Database_FromScene(Render *re, Scene *scene, int use_camera_view)
 	}
 	
 	init_render_world(re);	/* do first, because of ambient. also requires re->osa set correct */
-	if((re->r.mode & R_RAYTRACE) && (re->wrld.mode & WO_AMB_OCC)) {
-		if (re->wrld.ao_samp_method == WO_AOSAMP_HAMMERSLEY)
-			init_render_hammersley(re);
-		else if (re->wrld.ao_samp_method == WO_AOSAMP_CONSTANT)
-			init_ao_sphere(&re->wrld);
+	if(re->r.mode & R_RAYTRACE) {
+		init_render_qmcsampler(re);
+
+		if(re->wrld.mode & WO_AMB_OCC)
+			if (re->wrld.ao_samp_method == WO_AOSAMP_CONSTANT)
+				init_ao_sphere(&re->wrld);
 	}
 	
 	/* still bad... doing all */
@@ -5439,11 +5435,12 @@ void RE_Database_Baking(Render *re, Scene *scene, int type, Object *actob)
 	}
 	
 	init_render_world(re);	/* do first, because of ambient. also requires re->osa set correct */
-	if((re->r.mode & R_RAYTRACE) && (re->wrld.mode & WO_AMB_OCC)) {
-		if (re->wrld.ao_samp_method == WO_AOSAMP_HAMMERSLEY)
-			init_render_hammersley(re);
-		else if (re->wrld.ao_samp_method == WO_AOSAMP_CONSTANT)
-			init_ao_sphere(&re->wrld);
+	if(re->r.mode & R_RAYTRACE) {
+		init_render_qmcsampler(re);
+		
+		if(re->wrld.mode & WO_AMB_OCC)
+			if (re->wrld.ao_samp_method == WO_AOSAMP_CONSTANT)
+				init_ao_sphere(&re->wrld);
 	}
 	
 	/* still bad... doing all */
diff --git a/source/blender/render/intern/source/rayshade.c b/source/blender/render/intern/source/rayshade.c
index d423abefe96..7ffed72329e 100644
--- a/source/blender/render/intern/source/rayshade.c
+++ b/source/blender/render/intern/source/rayshade.c
@@ -40,8 +40,9 @@
 #include "BKE_utildefines.h"
 
 #include "BLI_arithb.h"
-#include "BLI_rand.h"
+#include "BLI_blenlib.h"
 #include "BLI_jitter.h"
+#include "BLI_rand.h"
 
 #include "PIL_time.h"
 
@@ -729,8 +730,8 @@ static void hammersley_create(double *out, int n)
 
 struct QMCSampler *QMC_initSampler(int type, int tot)
 {	
-	QMCSampler *qsa = MEM_mallocN(sizeof(QMCSampler), "qmc sampler");
-	qsa->samp2d = MEM_mallocN(2*sizeof(double)*tot, "qmc sample table");
+	QMCSampler *qsa = MEM_callocN(sizeof(QMCSampler), "qmc sampler");
+	qsa->samp2d = MEM_callocN(2*sizeof(double)*tot, "qmc sample table");
 
 	qsa->tot = tot;
 	qsa->type = type;
@@ -871,27 +872,55 @@ static void QMC_sampleHemiCosine(float *vec, QMCSampler *qsa, int thread, int nu
 #endif
 
 /* called from convertBlenderScene.c */
-/* samples don't change per pixel, so build the samples in advance for efficiency */
-void init_lamp_hammersley(LampRen *lar)
+void init_render_qmcsampler(Render *re)
 {
-	lar->qsa = QMC_initSampler(SAMP_TYPE_HAMMERSLEY, lar->ray_totsamp);
+	re->qmcsamplers= MEM_callocN(sizeof(ListBase)*BLENDER_MAX_THREADS, "QMCListBase");
 }
 
-void init_render_hammersley(Render *re)
+QMCSampler *get_thread_qmcsampler(Render *re, int thread, int type, int tot)
 {
-	re->qsa = QMC_initSampler(SAMP_TYPE_HAMMERSLEY, (re->wrld.aosamp * re->wrld.aosamp));
+	QMCSampler *qsa;
+
+	/* create qmc samplers as needed, since recursion makes it hard to
+	 * predict how many are needed */
+
+	for(qsa=re->qmcsamplers[thread].first; qsa; qsa=qsa->next) {
+		if(qsa->type == type && qsa->tot == tot && !qsa->used) {
+			qsa->used= 1;
+			return qsa;
+		}
+	}
+
+	qsa= QMC_initSampler(type, tot);
+	qsa->used= 1;
+	BLI_addtail(&re->qmcsamplers[thread], qsa);
+
+	return qsa;
 }
 
-void free_lamp_qmcsampler(LampRen *lar)
+void release_thread_qmcsampler(Render *re, int thread, QMCSampler *qsa)
 {
-	QMC_freeSampler(lar->qsa);
-	lar->qsa = NULL;
+	qsa->used= 0;
 }
 
 void free_render_qmcsampler(Render *re)
 {
-	QMC_freeSampler(re->qsa);
-	re->qsa = NULL;
+	QMCSampler *qsa, *next;
+	int a;
+
+	if(re->qmcsamplers) {
+		for(a=0; a<BLENDER_MAX_THREADS; a++) {
+			for(qsa=re->qmcsamplers[a].first; qsa; qsa=next) {
+				next= qsa->next;
+				QMC_freeSampler(qsa);
+			}
+
+			re->qmcsamplers[a].first= re->qmcsamplers[a].last= NULL;
+		}
+
+		MEM_freeN(re->qmcsamplers);
+		re->qmcsamplers= NULL;
+	}
 }
 
 static int adaptive_sample_variance(int samples, float *col, float *colsq, float thresh)
@@ -968,7 +997,7 @@ static void trace_refract(float *col, ShadeInput *shi, ShadeResult *shr)
 		else samp_type = SAMP_TYPE_HAMMERSLEY;
 			
 		/* all samples are generated per pixel */
-		qsa = QMC_initSampler(samp_type, max_samples);
+		qsa = get_thread_qmcsampler(&R, shi->thread, samp_type, max_samples);
 		QMC_initPixel(qsa, shi->thread);
 	} else 
 		max_samples = 1;
@@ -1026,7 +1055,8 @@ static void trace_refract(float *col, ShadeInput *shi, ShadeResult *shr)
 	col[2] /= (float)samples;
 	col[3] /= (float)samples;
 	
-	if (qsa) QMC_freeSampler(qsa);
+	if (qsa)
+		release_thread_qmcsampler(&R, shi->thread, qsa);
 }
 
 static void trace_reflect(float *col, ShadeInput *shi, ShadeResult *shr, float fresnelfac)
@@ -1053,7 +1083,7 @@ static void trace_reflect(float *col, ShadeInput *shi, ShadeResult *shr, float f
 		else samp_type = SAMP_TYPE_HAMMERSLEY;
 			
 		/* all samples are generated per pixel */
-		qsa = QMC_initSampler(samp_type, max_samples);
+		qsa = get_thread_qmcsampler(&R, shi->thread, samp_type, max_samples);
 		QMC_initPixel(qsa, shi->thread);
 	} else 
 		max_samples = 1;
@@ -1131,7 +1161,8 @@ static void trace_reflect(float *col, ShadeInput *shi, ShadeResult *shr, float f
 	col[1] /= (float)samples;
 	col[2] /= (float)samples;
 	
-	if (qsa) QMC_freeSampler(qsa);
+	if (qsa)
+		release_thread_qmcsampler(&R, shi->thread, qsa);
 }
 
 /* extern call from render loop */
@@ -1546,9 +1577,9 @@ void ray_ao_qmc(ShadeInput *shi, float *shadfac)
 		max_samples /= speedfac;
 		if (max_samples < 5) max_samples = 5;
 		
-		qsa = QMC_initSampler(SAMP_TYPE_HALTON, max_samples);
+		qsa = get_thread_qmcsampler(&R, shi->thread, SAMP_TYPE_HALTON, max_samples);
 	} else if (R.wrld.ao_samp_method==WO_AOSAMP_HAMMERSLEY)
-		qsa = R.qsa;
+		qsa = get_thread_qmcsampler(&R, shi->thread, SAMP_TYPE_HAMMERSLEY, max_samples);
 
 	QMC_initPixel(qsa, shi->thread);
 	
@@ -1621,7 +1652,8 @@ void ray_ao_qmc(ShadeInput *shi, float *shadfac)
 		shadfac[0]= shadfac[1]= shadfac[2]= 1.0f - fac/(float)samples;
 	}
 	
-	if ((qsa) && (qsa->type == SAMP_TYPE_HALTON)) QMC_freeSampler(qsa);
+	if (qsa)
+		release_thread_qmcsampler(&R, shi->thread, qsa);
 }
 
 /* extern call from shade_lamp_loop, ambient occlusion calculus */
@@ -1787,11 +1819,11 @@ static void ray_shadow_qmc(ShadeInput *shi, LampRen *lar, float *lampco, float *
 
 	/* sampling init */
 	if (lar->ray_samp_method==LA_SAMP_HALTON) {
-		qsa = QMC_initSampler(SAMP_TYPE_HALTON, max_samples);
-		qsa_jit = QMC_initSampler(SAMP_TYPE_HALTON, max_samples);
+		qsa = get_thread_qmcsampler(&R, shi->thread, SAMP_TYPE_HALTON, max_samples);
+		qsa_jit = get_thread_qmcsampler(&R, shi->thread, SAMP_TYPE_HALTON, max_samples);
 	} else if (lar->ray_samp_method==LA_SAMP_HAMMERSLEY) {
-		qsa = lar->qsa;
-		qsa_jit = QMC_initSampler(SAMP_TYPE_HAMMERSLEY, max_samples);
+		qsa = get_thread_qmcsampler(&R, shi->thread, SAMP_TYPE_HAMMERSLEY, max_samples);
+		qsa_jit = get_thread_qmcsampler(&R, shi->thread, SAMP_TYPE_HAMMERSLEY, max_samples);
 	}
 	
 	QMC_initPixel(qsa, shi->thread);
@@ -1921,8 +1953,10 @@ static void ray_shadow_qmc(ShadeInput *shi, LampRen *lar, float *lampco, float *
 	} else
 		shadfac[3]= 1.0f-fac/samples;
 
-	if (qsa_jit) QMC_freeSampler(qsa_jit);
-	if ((qsa) && (qsa->type == SAMP_TYPE_HALTON)) QMC_freeSampler(qsa);
+	if (qsa_jit)
+		release_thread_qmcsampler(&R, shi->thread, qsa_jit);
+	if (qsa)
+		release_thread_qmcsampler(&R, shi->thread, qsa);
 }
 
 static void ray_shadow_jitter(ShadeInput *shi, LampRen *lar, float *lampco, float *shadfac, Isect *isec)