== Render ==

Commit patch #7788, allow to set the render step, so it's
possible make render every N frames only.

The step is change in Scene buttons (F10), below start and
end frame buttons.

Also add a command line options (-j), so it's possible to
overwrite the file step (useful for renderfarm).

[ Brecht, this work with OpenGL renders and simulated
  the skipped frames, please double check ]

10 files changed, 72 insertions, 15 deletions

diff --git a/source/blender/blenkernel/BKE_blender.h b/source/blender/blenkernel/BKE_blender.h
index 5af8fde99c9..8dbb90372f0 100644
--- a/source/blender/blenkernel/BKE_blender.h
+++ b/source/blender/blenkernel/BKE_blender.h
@@ -41,7 +41,7 @@ struct ListBase;
 struct MemFile;
 
 #define BLENDER_VERSION			247
-#define BLENDER_SUBVERSION		3
+#define BLENDER_SUBVERSION		4
 
 #define BLENDER_MINVERSION		245
 #define BLENDER_MINSUBVERSION	15
diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index 0df965b2cc1..80defdbbf9c 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -7808,6 +7808,16 @@ static void do_versions(FileData *fd, Library *lib, Main *main)
 				ob->gameflag &= ~(OB_GHOST|OB_DYNAMIC|OB_RIGID_BODY|OB_SOFT_BODY|OB_COLLISION_RESPONSE);
 		}
 	}
+
+	if (main->versionfile < 247 || (main->versionfile == 247 && main->subversionfile < 4)){
+		Scene *sce= main->scene.first;
+		while(sce) {
+			if(sce->frame_step==0)
+				sce->frame_step= 1;
+			sce= sce->id.next;
+		}
+	}
+
 	/* WATCH IT!!!: pointers from libdata have not been converted yet here! */
 	/* WATCH IT 2!: Userdef struct init has to be in src/usiblender.c! */
 
diff --git a/source/blender/include/blendef.h b/source/blender/include/blendef.h
index a7f7bc2e4b8..7fd607f6feb 100644
--- a/source/blender/include/blendef.h
+++ b/source/blender/include/blendef.h
@@ -113,6 +113,7 @@
 #define	F_CFRA			((float)(G.scene->r.cfra))
 #define	SFRA			(G.scene->r.sfra)
 #define	EFRA			(G.scene->r.efra)
+#define STFRA			(G.scene->frame_step)
 #define PSFRA			((G.scene->r.psfra != 0)? (G.scene->r.psfra): (G.scene->r.sfra))
 #define PEFRA			((G.scene->r.psfra != 0)? (G.scene->r.pefra): (G.scene->r.efra))
 #define FRA2TIME(a)           ((((double) G.scene->r.frs_sec_base) * (a)) / G.scene->r.frs_sec)
diff --git a/source/blender/makesdna/DNA_scene_types.h b/source/blender/makesdna/DNA_scene_types.h
index 32522d1e866..3888cb48520 100644
--- a/source/blender/makesdna/DNA_scene_types.h
+++ b/source/blender/makesdna/DNA_scene_types.h
@@ -553,6 +553,10 @@ typedef struct Scene {
 
 	/* Sculptmode data */
 	struct SculptData sculptdata;
+
+	/* frame step. */
+	int frame_step;
+	int pad;
 } Scene;
 
 
diff --git a/source/blender/python/api2_2x/sceneRender.c b/source/blender/python/api2_2x/sceneRender.c
index 7958e66b44f..7f88acd3a87 100644
--- a/source/blender/python/api2_2x/sceneRender.c
+++ b/source/blender/python/api2_2x/sceneRender.c
@@ -496,7 +496,7 @@ PyObject *RenderData_Render( BPy_RenderData * self )
 
 		tstate = PyEval_SaveThread();
 
-		RE_BlenderAnim(re, G.scene, G.scene->r.sfra, G.scene->r.efra);
+		RE_BlenderAnim(re, G.scene, G.scene->r.sfra, G.scene->r.efra, G.scene->frame_step);
 
 		BPY_do_all_scripts(SCRIPT_POSTRENDER, 0);
 
@@ -599,7 +599,7 @@ PyObject *RenderData_RenderAnim( BPy_RenderData * self )
 			BPY_do_all_scripts(SCRIPT_RENDER, 1);
 
 		tstate = PyEval_SaveThread();
-		RE_BlenderAnim(re, G.scene, G.scene->r.sfra, G.scene->r.efra);
+		RE_BlenderAnim(re, G.scene, G.scene->r.sfra, G.scene->r.efra, G.scene->frame_step);
 
 		if (G.f & G_DOSCRIPTLINKS)
 			BPY_do_all_scripts(SCRIPT_POSTRENDER, 1);
diff --git a/source/blender/render/extern/include/RE_pipeline.h b/source/blender/render/extern/include/RE_pipeline.h
index 64cf7fcb37b..60557403143 100644
--- a/source/blender/render/extern/include/RE_pipeline.h
+++ b/source/blender/render/extern/include/RE_pipeline.h
@@ -185,7 +185,7 @@ void RE_TileProcessor(struct Render *re, int firsttile, int threaded);
 
 /* only RE_NewRender() needed, main Blender render calls */
 void RE_BlenderFrame(struct Render *re, struct Scene *scene, int frame);
-void RE_BlenderAnim(struct Render *re, struct Scene *scene, int sfra, int efra);
+void RE_BlenderAnim(struct Render *re, struct Scene *scene, int sfra, int efra, int tfra);
 
 void RE_ReadRenderResult(struct Scene *scene, struct Scene *scenode);
 void RE_WriteRenderResult(RenderResult *rr, char *filename, int compress);
diff --git a/source/blender/render/intern/source/pipeline.c b/source/blender/render/intern/source/pipeline.c
index bf2a72b4f9b..9d272d04506 100644
--- a/source/blender/render/intern/source/pipeline.c
+++ b/source/blender/render/intern/source/pipeline.c
@@ -2559,10 +2559,12 @@ static void do_write_image_or_movie(Render *re, Scene *scene, bMovieHandle *mh)
 }
 
 /* saves images to disk */
-void RE_BlenderAnim(Render *re, Scene *scene, int sfra, int efra)
+void RE_BlenderAnim(Render *re, Scene *scene, int sfra, int efra, int tfra)
 {
 	bMovieHandle *mh= BKE_get_movie_handle(scene->r.imtype);
+	unsigned int lay;
 	int cfrao= scene->r.cfra;
+	int nfra;
 	
 	/* do not fully call for each frame, it initializes & pops output window */
 	if(!render_initialize_from_scene(re, scene, 0))
@@ -2591,12 +2593,27 @@ void RE_BlenderAnim(Render *re, Scene *scene, int sfra, int efra)
 			}
 		}
 	} else {
-		for(scene->r.cfra= sfra; scene->r.cfra<=efra; scene->r.cfra++) {
+		for(nfra= sfra, scene->r.cfra= sfra; scene->r.cfra<=efra; scene->r.cfra++) {
 			char name[FILE_MAX];
 			
 			/* only border now, todo: camera lens. (ton) */
 			render_initialize_from_scene(re, scene, 1);
-			
+
+			if(nfra!=scene->r.cfra) {
+				/*
+				 * Skip this frame, but update for physics and particles system.
+				 * From convertblender.c:
+				 * in localview, lamps are using normal layers, objects only local bits.
+				 */
+				if(scene->lay & 0xFF000000)
+					lay= scene->lay & 0xFF000000;
+				else
+					lay= scene->lay;
+
+				scene_update_for_newframe(scene, lay);
+				continue;
+			}
+
 			if (scene->r.mode & (R_NO_OVERWRITE | R_TOUCH) ) {
 				BKE_makepicstring(name, scene->r.pic, scene->r.cfra, scene->r.imtype);
 			}
@@ -2626,6 +2643,7 @@ void RE_BlenderAnim(Render *re, Scene *scene, int sfra, int efra)
 				
 				break;
 			}
+			nfra+= tfra;
 		}
 	}
 	
diff --git a/source/blender/src/buttons_scene.c b/source/blender/src/buttons_scene.c
index f2e20356f21..8ea71ce38dc 100644
--- a/source/blender/src/buttons_scene.c
+++ b/source/blender/src/buttons_scene.c
@@ -2315,12 +2315,13 @@ static void render_panel_anim(void)
 	uiBlockEndAlign(block);
 
 	uiBlockSetCol(block, TH_AUTO);
-	uiDefBut(block, BUT,B_PLAYANIM, "PLAY",692,40,94,33, 0, 0, 0, 0, 0, "Play rendered images/avi animation (Ctrl+F11), (Play Hotkeys: A-Noskip, P-PingPong)");
-	uiDefButS(block, NUM, B_RTCHANGED, "rt:",789,40,95,33, &G.rt, -1000.0, 1000.0, 0, 0, "General testing/debug button");
+	uiDefBut(block, BUT,B_PLAYANIM, "PLAY",692,50,94,33, 0, 0, 0, 0, 0, "Play rendered images/avi animation (Ctrl+F11), (Play Hotkeys: A-Noskip, P-PingPong)");
+	uiDefButS(block, NUM, B_RTCHANGED, "rt:",789,50,95,33, &G.rt, -1000.0, 1000.0, 0, 0, "General testing/debug button");
 
 	uiBlockBeginAlign(block);
-	uiDefButI(block, NUM,REDRAWSEQ,"Sta:",692,10,94,24, &G.scene->r.sfra,1.0,MAXFRAMEF, 0, 0, "The start frame of the animation (inclusive)");
-	uiDefButI(block, NUM,REDRAWSEQ,"End:",789,10,95,24, &G.scene->r.efra,SFRA,MAXFRAMEF, 0, 0, "The end  frame of the animation  (inclusive)");
+	uiDefButI(block, NUM,REDRAWSEQ,"Sta:",692,20,94,24, &G.scene->r.sfra,1.0,MAXFRAMEF, 0, 0, "The start frame of the animation (inclusive)");
+	uiDefButI(block, NUM,REDRAWSEQ,"End:",789,20,95,24, &G.scene->r.efra,SFRA,MAXFRAMEF, 0, 0, "The end  frame of the animation  (inclusive)");
+	uiDefButI(block, NUM,REDRAWSEQ,"Step:",692,0,192,18, &G.scene->frame_step, 1.0, MAXFRAMEF, 0, 0, "Frame Step");
 	uiBlockEndAlign(block);
 }
 
diff --git a/source/blender/src/renderwin.c b/source/blender/src/renderwin.c
index c26eedd26fd..598b71930ed 100644
--- a/source/blender/src/renderwin.c
+++ b/source/blender/src/renderwin.c
@@ -1132,7 +1132,7 @@ static void do_render(int anim)
 	}
 	
 	if(anim)
-		RE_BlenderAnim(re, G.scene, G.scene->r.sfra, G.scene->r.efra);
+		RE_BlenderAnim(re, G.scene, G.scene->r.sfra, G.scene->r.efra, G.scene->frame_step);
 	else
 		RE_BlenderFrame(re, G.scene, G.scene->r.cfra);
 
@@ -1338,16 +1338,28 @@ void BIF_do_ogl_render(View3D *v3d, int anim)
 
 	if(anim) {
 		bMovieHandle *mh= BKE_get_movie_handle(G.scene->r.imtype);
+		unsigned int lay;
 		int cfrao= CFRA;
+		int nfra;
 		
 		if(BKE_imtype_is_movie(G.scene->r.imtype))
 			mh->start_movie(&G.scene->r, winx, winy);
 		
-		for(CFRA= SFRA; CFRA<=EFRA; CFRA++) {
+		for(nfra= SFRA, CFRA= SFRA; CFRA<=EFRA; CFRA++) {
 			/* user event can close window */
 			if(render_win==NULL)
 				break;
 
+			if(nfra!=CFRA) {
+				if(G.scene->lay & 0xFF000000)
+					lay= G.scene->lay & 0xFF000000;
+				else
+					lay= G.scene->lay;
+
+				scene_update_for_newframe(G.scene, lay);
+				continue;
+			}
+
 			do_ogl_view3d_render(re, v3d, winx, winy);
 			glReadPixels(0, 0, winx, winy, GL_RGBA, GL_UNSIGNED_BYTE, rr->rect32);
 			if((G.scene->r.scemode & R_STAMP_INFO) && (G.scene->r.stamp & R_STAMP_DRAW)) {
@@ -1382,6 +1394,7 @@ void BIF_do_ogl_render(View3D *v3d, int anim)
 			printf("\n");
 			
 			if(test_break()) break;
+			nfra+= STFRA;
 		}
 		
 		if(BKE_imtype_is_movie(G.scene->r.imtype))
diff --git a/source/creator/creator.c b/source/creator/creator.c
index ac81557110f..dffa755b264 100644
--- a/source/creator/creator.c
+++ b/source/creator/creator.c
@@ -202,6 +202,7 @@ static void print_help(void)
 	printf ("    -p <sx> <sy>\tOpen with lower left corner at <sx>, <sy>\n");
 	printf ("    -m\t\tRead from disk (Don't buffer)\n");
 	printf ("    -f <fps> <fps-base>\t\tSpecify FPS to start with\n");
+	printf ("    -j <frame>\tSet frame step to <frame>\n");
 				
 	printf ("\nWindow options:\n");
 	printf ("  -w\t\tForce opening with borders (default)\n");
@@ -623,7 +624,7 @@ int main(int argc, char **argv)
 						if (G.f & G_DOSCRIPTLINKS)
 							BPY_do_all_scripts(SCRIPT_RENDER, 0);
 
-						RE_BlenderAnim(re, G.scene, frame, frame);
+						RE_BlenderAnim(re, G.scene, frame, frame, G.scene->frame_step);
 
 						BPY_do_all_scripts(SCRIPT_POSTRENDER, 0);
 					}
@@ -638,7 +639,7 @@ int main(int argc, char **argv)
 					if (G.f & G_DOSCRIPTLINKS)
 						BPY_do_all_scripts(SCRIPT_RENDER, 1);
 
-					RE_BlenderAnim(re, G.scene, G.scene->r.sfra, G.scene->r.efra);
+					RE_BlenderAnim(re, G.scene, G.scene->r.sfra, G.scene->r.efra, G.scene->frame_step);
 
 					if (G.f & G_DOSCRIPTLINKS)
 						BPY_do_all_scripts(SCRIPT_POSTRENDER, 1);
@@ -669,6 +670,15 @@ int main(int argc, char **argv)
 					printf("\nError: no blend loaded. cannot use '-e'.\n");
 				}
 				break;
+			case 'j':
+				a++;
+				if(G.scene) {
+					int fstep= MIN2(MAXFRAME, MAX2(1, atoi(argv[a])));
+					if (a < argc) (G.scene->frame_step) = fstep;
+				} else {
+					printf("\nError: no blend loaded. cannot use '-j'.\n");
+				}
+				break;
 			case 'P':
 				a++;
 				if (a < argc) {