6 files changed, 40 insertions, 16 deletions

diff --git a/source/blender/blenlib/BLI_threads.h b/source/blender/blenlib/BLI_threads.h
index 60ecce3f9d8..39162b8bd91 100644
--- a/source/blender/blenlib/BLI_threads.h
+++ b/source/blender/blenlib/BLI_threads.h
@@ -50,5 +50,6 @@ void	BLI_end_threads		(struct ListBase *threadbase);
 void	BLI_lock_thread		(int type);
 void	BLI_unlock_thread	(int type);
 
+int		BLI_system_thread_count( void ); /* gets the number of threads the system can make use of */
 #endif
 
diff --git a/source/blender/blenlib/intern/threads.c b/source/blender/blenlib/intern/threads.c
index 1f05070b034..d6048b4bade 100644
--- a/source/blender/blenlib/intern/threads.c
+++ b/source/blender/blenlib/intern/threads.c
@@ -32,6 +32,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <pthread.h>
+#include <unistd.h> /* for checking system threads */
 
 #include "MEM_guardedalloc.h"
 
@@ -224,4 +225,16 @@ void BLI_unlock_thread(int type)
 		pthread_mutex_unlock(&_custom1_lock);
 }
 
+/* how many threads are native on this system? */
+int BLI_system_thread_count( void )
+{
+	int t = (int)sysconf(_SC_NPROCESSORS_ONLN);
+	if (t>RE_MAX_THREAD)
+		return RE_MAX_THREAD;
+	if (t<1)
+		return 1;
+	
+	return t;
+}
+
 /* eof */
diff --git a/source/blender/makesdna/DNA_scene_types.h b/source/blender/makesdna/DNA_scene_types.h
index 7a577d22685..39e27667645 100644
--- a/source/blender/makesdna/DNA_scene_types.h
+++ b/source/blender/makesdna/DNA_scene_types.h
@@ -573,8 +573,9 @@ typedef struct Scene {
 #define R_GAUSS      	0x20000
 		/* fbuf obsolete... */
 #define R_FBUF			0x40000
-		/* threads obsolete... is there for old files */
-#define R_THREADS		0x80000
+		/* threads obsolete... is there for old files, now use for autodetect threads */
+#define R_THREADS		0x80000 
+
 #define R_SPEED			0x100000
 #define R_SSS			0x200000
 #define R_NO_OVERWRITE	0x400000 /* skip existing files */
diff --git a/source/blender/render/intern/source/pipeline.c b/source/blender/render/intern/source/pipeline.c
index 177d7ec58e2..5de109a16f4 100644
--- a/source/blender/render/intern/source/pipeline.c
+++ b/source/blender/render/intern/source/pipeline.c
@@ -117,7 +117,7 @@ static struct ListBase RenderList= {NULL, NULL};
 Render R;
 
 /* commandline thread override */
-static int commandline_threads= 0;
+static int commandline_threads= -1;
 
 /* ********* alloc and free ******** */
 
@@ -1108,8 +1108,11 @@ void RE_InitState(Render *re, Render *source, RenderData *rd, int winx, int winy
 		/* we clip faces with a minimum of 2 pixel boundary outside of image border. see zbuf.c */
 		re->clipcrop= 1.0f + 2.0f/(float)(re->winx>re->winy?re->winy:re->winx);
 		
-		if(commandline_threads>0 && commandline_threads<=BLENDER_MAX_THREADS)
+		if (rd->mode & R_THREADS || commandline_threads == 0) { /* Automatic threads */
+			re->r.threads = BLI_system_thread_count();
+		} else if(commandline_threads >= 1 && commandline_threads<=BLENDER_MAX_THREADS) {
 			re->r.threads= commandline_threads;
+		}
 	}
 }
 
@@ -2651,8 +2654,11 @@ void RE_ReadRenderResult(Scene *scene, Scene *scenode)
 
 void RE_set_max_threads(int threads)
 {
-	if(threads>0 && threads<=BLENDER_MAX_THREADS)
+	if (threads==0) {
+		commandline_threads = BLI_system_thread_count();
+	} else if(threads>=1 && threads<=BLENDER_MAX_THREADS) {
 		commandline_threads= threads;
-	else
+	} else {
 		printf("Error, threads has to be in range 1-%d\n", BLENDER_MAX_THREADS);
+	}
 }
diff --git a/source/blender/src/buttons_scene.c b/source/blender/src/buttons_scene.c
index 055674097b0..7654bc44b75 100644
--- a/source/blender/src/buttons_scene.c
+++ b/source/blender/src/buttons_scene.c
@@ -2022,7 +2022,17 @@ static void render_panel_output(void)
 	}
 	uiBlockEndAlign(block);
 
-	uiDefButS(block, NUM, B_NOP, "Threads:",				10, 63, 100, 20, &G.scene->r.threads, 1, BLENDER_MAX_THREADS, 0, 0, "Amount of threads for render (takes advantage of multi-core and multi-processor computers)");
+	uiBlockBeginAlign(block);
+	uiDefIconButBitI(block, TOG, R_THREADS, B_REDR, ICON_AUTO,	10, 63, 20, 20, &G.scene->r.mode, 0.0, 0.0, 0, 0, "Automatic threads from system");
+	if (G.scene->r.mode & R_THREADS) {
+		char thread_str[32];
+		sprintf(thread_str, "Threads: %d", BLI_system_thread_count());
+		uiDefBut(block, LABEL, 0, thread_str, 30, 63,80,20, 0, 0, 0, 0, 0, "");
+	} else {
+		uiDefButS(block, NUM, B_NOP, "Threads:", 35, 63, 80, 20, &G.scene->r.threads, 1, BLENDER_MAX_THREADS, 0, 0, "Amount of threads for render (takes advantage of multi-core and multi-processor computers)");
+	}
+	uiBlockEndAlign(block);
+	
 	uiBlockSetCol(block, TH_AUTO);
 		
 	uiBlockBeginAlign(block);
diff --git a/source/creator/creator.c b/source/creator/creator.c
index d4a0bb49614..ab6f9681978 100644
--- a/source/creator/creator.c
+++ b/source/creator/creator.c
@@ -200,15 +200,8 @@ static void print_help(void)
 	printf ("    (formats that can be compiled into blender, not available on all systems)\n");
 	printf ("    \tHDR TIFF EXR MULTILAYER MPEG AVICODEC QUICKTIME CINEON DPX DDS\n");
 	printf ("    -x <bool>\tSet option to add the file extension to the end of the file.\n");
-	printf ("    -t <threads>\tUse amount of <threads> for rendering\n");
-	/*Add these later - Campbell*/
-	/*
-	printf ("    -colorchannel <type>\tColors to save, valid types are: BW RGB RGBA \n");
-	printf ("    -compression <type>\t Use with EXR format, valid types are..\n");
-	printf ("    \tZIP Pxr24 PIZ RLE\n");
-	printf ("    -zbuf <bool>\tUse with EXR format, set the zbuf save option\n");
-	printf ("    -halffloat <bool>\tUse with EXR format, set the half float option\n");
-	printf ("    -preview <bool>\tUse with EXR format, save a jpeg for viewing as well as the EXR\n");*/
+	printf ("    -t <threads>\tUse amount of <threads> for rendering.\n");
+	printf ("      [1-8], 0 for systems processor count.\n");
 	printf ("\nAnimation playback options:\n");
 	printf ("  -a <file(s)>\tPlayback <file(s)>, only operates this way when -b is not used.\n");
 	printf ("    -p <sx> <sy>\tOpen with lower left corner at <sx>, <sy>\n");