Smoke: Start fixing scaling issues which happen with non cube-shaped domains.

Detail: Smoke solver and Blender side of smoke now share the same cell length.

First reported by the Sintel artists long ago, again reported by MiikaH.

Part of my Smoke Development Project Phase III.

1 files changed, 20 insertions, 24 deletions

diff --git a/source/blender/blenkernel/intern/smoke.c b/source/blender/blenkernel/intern/smoke.c
index 06f98b0e840..b33ae202f1a 100644
--- a/source/blender/blenkernel/intern/smoke.c
+++ b/source/blender/blenkernel/intern/smoke.c
@@ -198,8 +198,6 @@ static int smokeModifier_init (SmokeModifierData *smd, Object *ob, Scene *scene,
 		// calc other res with max_res provided
 		sub_v3_v3v3(size, max, min);
 
-		// printf("size: %f, %f, %f\n", size[0], size[1], size[2]);
-
 		// prevent crash when initializing a plane as domain
 		if((size[0] < FLT_EPSILON) || (size[1] < FLT_EPSILON) || (size[2] < FLT_EPSILON))
 			return 0;
@@ -209,14 +207,16 @@ static int smokeModifier_init (SmokeModifierData *smd, Object *ob, Scene *scene,
 			if(size[0] > size[2])
 			{
 				scale = res / size[0];
-				smd->domain->dx = size[0] / res; // dx is in global coords
+				smd->domain->scale = size[0];
+				smd->domain->dx = 1.0f / res; 
 				smd->domain->res[0] = res;
 				smd->domain->res[1] = (int)(size[1] * scale + 0.5);
 				smd->domain->res[2] = (int)(size[2] * scale + 0.5);
 			}
 			else {
 				scale = res / size[2];
-				smd->domain->dx = size[2] / res; // dx is in global coords
+				smd->domain->scale = size[2];
+				smd->domain->dx = 1.0f / res;
 				smd->domain->res[2] = res;
 				smd->domain->res[0] = (int)(size[0] * scale + 0.5);
 				smd->domain->res[1] = (int)(size[1] * scale + 0.5);
@@ -226,25 +226,24 @@ static int smokeModifier_init (SmokeModifierData *smd, Object *ob, Scene *scene,
 			if(size[1] > size[2])
 			{
 				scale = res / size[1];
-				smd->domain->dx = size[1] / res; // dx is in global coords
+				smd->domain->scale = size[1];
+				smd->domain->dx = 1.0f / res; 
 				smd->domain->res[1] = res;
 				smd->domain->res[0] = (int)(size[0] * scale + 0.5);
 				smd->domain->res[2] = (int)(size[2] * scale + 0.5);
 			}
 			else {
 				scale = res / size[2];
-				smd->domain->dx = size[2] / res;
+				smd->domain->scale = size[2];
+				smd->domain->dx = 1.0f / res;
 				smd->domain->res[2] = res;
 				smd->domain->res[0] = (int)(size[0] * scale + 0.5);
 				smd->domain->res[1] = (int)(size[1] * scale + 0.5);
 			}
 		}
 
-		// printf("smd->domain->dx: %f\n", smd->domain->dx);
-
 		// TODO: put in failsafe if res<=0 - dg
 
-		// printf("res[0]: %d, res[1]: %d, res[2]: %d\n", smd->domain->res[0], smd->domain->res[1], smd->domain->res[2]);
 		// dt max is 0.1
 		smd->domain->fluid = smoke_init(smd->domain->res, smd->domain->p0, DT_DEFAULT);
 		smd->time = scene->r.cfra;
@@ -256,8 +255,6 @@ static int smokeModifier_init (SmokeModifierData *smd, Object *ob, Scene *scene,
 			smd->domain->res_wt[1] = smd->domain->res[1] * (smd->domain->amplify + 1);			
 			smd->domain->res_wt[2] = smd->domain->res[2] * (smd->domain->amplify + 1);			
 			smd->domain->dx_wt = smd->domain->dx / (smd->domain->amplify + 1);		
-			// printf("smd->domain->amplify: %d\n",  smd->domain->amplify);
-			// printf("(smd->domain->flags & MOD_SMOKE_HIGHRES)\n");
 		}
 
 		if(!smd->domain->shadow)
@@ -268,7 +265,6 @@ static int smokeModifier_init (SmokeModifierData *smd, Object *ob, Scene *scene,
 		if(smd->domain->wt)	
 		{
 			smoke_initWaveletBlenderRNA(smd->domain->wt, &(smd->domain->strength));
-			// printf("smoke_initWaveletBlenderRNA\n");
 		}
 		return 1;
 	}
@@ -303,8 +299,6 @@ static int smokeModifier_init (SmokeModifierData *smd, Object *ob, Scene *scene,
 
 			DM_ensure_tessface(dm);
 			fill_scs_points(ob, dm, scs);
-
-			// DEBUG printf("scs->dx: %f\n", scs->dx);
 		}
 
 		if(!smd->coll->bvhtree)
@@ -1184,7 +1178,7 @@ static void update_obstacles(Scene *scene, Object *ob, SmokeDomainSettings *sds,
 				// DG TODO: cap velocity to maxVelMag (or maxvel)
 
 				// oldpos + velocity * dt = newpos
-				get_cell(sds->p0, sds->res, sds->dx, cOldpos /* use current position here instead of "pos" */, cell, 0);
+				get_cell(sds->p0, sds->res, sds->dx*sds->scale, cOldpos /* use current position here instead of "pos" */, cell, 0);
 
 				// check if cell is valid (in the domain boundary)
 				for(j = 0; j < 3; j++)
@@ -1329,7 +1323,7 @@ static void update_flowsfluids(Scene *scene, Object *ob, SmokeDomainSettings *sd
 					// copy_v3_v3(pos, pa->state.co);
 					// mul_m4_v3(ob->imat, pos);
 					// 1. get corresponding cell
-					get_cell(sds->p0, sds->res, sds->dx, state.co, cell, 0);																	
+					get_cell(sds->p0, sds->res, sds->dx*sds->scale, state.co, cell, 0);																	
 					// check if cell is valid (in the domain boundary)									
 					for(i = 0; i < 3; i++)									
 					{										
@@ -1555,9 +1549,9 @@ static void update_effectors(Scene *scene, Object *ob, SmokeDomainSettings *sds,
 			vel[1] = velocity_y[index];
 			vel[2] = velocity_z[index];
 
-			voxelCenter[0] = sds->p0[0] + sds->dx *  x + sds->dx * 0.5;
-			voxelCenter[1] = sds->p0[1] + sds->dx *  y + sds->dx * 0.5;
-			voxelCenter[2] = sds->p0[2] + sds->dx *  z + sds->dx * 0.5;
+			voxelCenter[0] = sds->p0[0] + sds->dx * sds->scale * x + sds->dx * sds->scale * 0.5;
+			voxelCenter[1] = sds->p0[1] + sds->dx * sds->scale * y + sds->dx * sds->scale * 0.5;
+			voxelCenter[2] = sds->p0[2] + sds->dx * sds->scale * z + sds->dx * sds->scale * 0.5;
 
 			pd_point_from_loc(scene, voxelCenter, vel, index, &epoint);
 			pdDoEffectors(effectors, NULL, sds->effector_weights, &epoint, retvel, NULL);
@@ -1667,6 +1661,7 @@ void smokeModifier_do(SmokeModifierData *smd, Scene *scene, Object *ob, DerivedM
 			Base *base = scene->base.first;
 			int changed = 0;
 			float dx = FLT_MAX;
+			float scale = 1.0f;
 			int haveDomain = 0;
 
 			for ( ; base; base = base->next) 
@@ -1677,9 +1672,10 @@ void smokeModifier_do(SmokeModifierData *smd, Scene *scene, Object *ob, DerivedM
 				{
 					SmokeDomainSettings *sds = smd2->domain;
 
-					if(sds->dx < dx)
+					if(sds->dx * sds->scale < dx)
 					{
 						dx = sds->dx;
+						scale = sds->scale;
 						changed = 1;
 					}
 
@@ -1692,9 +1688,9 @@ void smokeModifier_do(SmokeModifierData *smd, Scene *scene, Object *ob, DerivedM
 			
 			if(changed)
 			{
-				if(dx != scs->dx)
+				if(dx*scale != scs->dx)
 				{
-					scs->dx = dx;
+					scs->dx = dx*scale;
 					smokeModifier_reset(smd);
 				}
 			}
@@ -1813,7 +1809,7 @@ void smokeModifier_do(SmokeModifierData *smd, Scene *scene, Object *ob, DerivedM
 		if((int)smd->time == startframe && (cache->flag & PTCACHE_OUTDATED || cache->last_exact==0)) {
 			// create shadows straight after domain initialization so we get nice shadows for startframe, too
 			if(get_lamp(scene, light))
-				smoke_calc_transparency(sds->shadow, smoke_get_density(sds->fluid), sds->p0, sds->p1, sds->res, sds->dx, light, calc_voxel_transp, -7.0*sds->dx);
+				smoke_calc_transparency(sds->shadow, smoke_get_density(sds->fluid), sds->p0, sds->p1, sds->res, sds->dx * sds->scale, light, calc_voxel_transp, -7.0*sds->dx * sds->scale);
 
 			if(sds->wt)
 			{
@@ -1844,7 +1840,7 @@ void smokeModifier_do(SmokeModifierData *smd, Scene *scene, Object *ob, DerivedM
 
 		// create shadows before writing cache so they get stored
 		if(get_lamp(scene, light))
-			smoke_calc_transparency(sds->shadow, smoke_get_density(sds->fluid), sds->p0, sds->p1, sds->res, sds->dx, light, calc_voxel_transp, -7.0*sds->dx);
+			smoke_calc_transparency(sds->shadow, smoke_get_density(sds->fluid), sds->p0, sds->p1, sds->res, sds->dx * sds->scale, light, calc_voxel_transp, -7.0*sds->dx * sds->scale);
 
 		if(sds->wt)
 		{