Changes to Color Management

After testing and feedback, I've decided to slightly modify the way color 
management works internally. While the previous method worked well for 
rendering, was a smaller transition and had some advantages over this
new method, it was a bit more ambiguous, and was making things difficult 
for other areas such as compositing.

This implementation now considers all color data (with only a couple of 
exceptions such as brush colors) to be stored in linear RGB color space, 
rather than sRGB as previously. This brings it in line with Nuke, which also 
operates this way, quite successfully. Color swatches, pickers, color ramp 
display are now gamma corrected to display gamma so you can see what 
you're doing, but the numbers themselves are considered linear. This 
makes understanding blending modes more clear (a 0.5 value on overlay 
will not change the result now) as well as making color swatches act more 
predictably in the compositor, however bringing over color values from 
applications like photoshop or gimp, that operate in a gamma space, 
will give identical results.

This commit will convert over existing files saved by earlier 2.5 versions to 
work generally the same, though there may be some slight differences with 
things like textures. Now that we're set on changing other areas of shading, 
this won't be too disruptive overall.

I've made a diagram explaining the pipeline here:
http://mke3.net/blender/devel/2.5/25_linear_workflow_pipeline.png

and some docs here:
http://www.blender.org/development/release-logs/blender-250/color-management/

29 files changed, 272 insertions, 158 deletions

diff --git a/source/blender/blenkernel/BKE_blender.h b/source/blender/blenkernel/BKE_blender.h
index ebeec31c984..7bbcb63a7f5 100644
--- a/source/blender/blenkernel/BKE_blender.h
+++ b/source/blender/blenkernel/BKE_blender.h
@@ -43,7 +43,7 @@ struct bContext;
 struct ReportList;
 
 #define BLENDER_VERSION			250
-#define BLENDER_SUBVERSION		7
+#define BLENDER_SUBVERSION		8
 
 #define BLENDER_MINVERSION		250
 #define BLENDER_MINSUBVERSION	0
diff --git a/source/blender/blenkernel/BKE_colortools.h b/source/blender/blenkernel/BKE_colortools.h
index c83a260690b..c571688737a 100644
--- a/source/blender/blenkernel/BKE_colortools.h
+++ b/source/blender/blenkernel/BKE_colortools.h
@@ -34,12 +34,6 @@ struct CurveMap;
 struct ImBuf;
 struct rctf;
 
-void 				gamma_correct_rec709(float *c, float gamma);
-void				gamma_correct(float *c, float gamma);
-float				srgb_to_linearrgb(float c);
-float				linearrgb_to_srgb(float c);
-void				color_manage_linearize(float *col_to, float *col_from);
-
 void				floatbuf_to_srgb_byte(float *rectf, unsigned char *rectc, int x1, int x2, int y1, int y2, int w);
 void				floatbuf_to_byte(float *rectf, unsigned char *rectc, int x1, int x2, int y1, int y2, int w);
 
diff --git a/source/blender/blenkernel/intern/colortools.c b/source/blender/blenkernel/intern/colortools.c
index f3448a60b5a..48e42bc539f 100644
--- a/source/blender/blenkernel/intern/colortools.c
+++ b/source/blender/blenkernel/intern/colortools.c
@@ -58,52 +58,6 @@
 #include "IMB_imbuf.h"
 #include "IMB_imbuf_types.h"
 
-/* ********************************* color transforms ********************************* */
-
-/*Transform linear RGB values to nonlinear RGB values. Rec.
-  709 is ITU-R Recommendation BT. 709 (1990) ``Basic
-  Parameter Values for the HDTV Standard for the Studio and
-  for International Programme Exchange'', formerly CCIR Rec.
-  709.*/
-void gamma_correct_rec709(float *c, float gamma)
-{
-	/* Rec. 709 gamma correction. */
-	const float cc = 0.018f;
-	
-	if (*c < cc)
-	    *c *= ((1.099f * (float)powf(cc, gamma)) - 0.099f) * (1.0f/cc);
-	else 
-	    *c = (1.099f * (float)powf(*c, gamma)) - 0.099f;
-}
-
-void gamma_correct(float *c, float gamma)
-{
-	*c = powf((*c), gamma);
-}
-
-float srgb_to_linearrgb(float c)
-{
-	if (c < 0.04045f)
-		return (c < 0.0f)? 0.0f: c*(1.0f/12.92f);
-	else
-		return powf((c + 0.055f)*(1.0f/1.055f), 2.4f);
-}
-
-float linearrgb_to_srgb(float c)
-{
-	if (c < 0.0031308f)
-		return (c < 0.0f)? 0.0f: c * 12.92f;
-	else
-		return  1.055f * powf(c, 1.0f/2.4f) - 0.055f;
-}
-
-/* utility function convert an RGB triplet from sRGB to linear RGB color space */
-void color_manage_linearize(float *col_to, float *col_from)
-{
-	col_to[0] = srgb_to_linearrgb(col_from[0]);
-	col_to[1] = srgb_to_linearrgb(col_from[1]);
-	col_to[2] = srgb_to_linearrgb(col_from[2]);
-}
 
 void floatbuf_to_srgb_byte(float *rectf, unsigned char *rectc, int x1, int x2, int y1, int y2, int w)
 {
diff --git a/source/blender/blenkernel/intern/object.c b/source/blender/blenkernel/intern/object.c
index 1e047380641..41255415b67 100644
--- a/source/blender/blenkernel/intern/object.c
+++ b/source/blender/blenkernel/intern/object.c
@@ -795,7 +795,7 @@ void *add_lamp(char *name)
 	la->sun_intensity = 1.0f;
 	la->skyblendtype= MA_RAMP_ADD;
 	la->skyblendfac= 1.0f;
-	la->sky_colorspace= BLI_CS_CIE;
+	la->sky_colorspace= BLI_XYZ_CIE;
 	la->sky_exposure= 1.0f;
 	
 	curvemapping_initialize(la->curfalloff);
diff --git a/source/blender/blenlib/BLI_math_color.h b/source/blender/blenlib/BLI_math_color.h
index b2d14f3ecbd..7444e01c3a6 100644
--- a/source/blender/blenlib/BLI_math_color.h
+++ b/source/blender/blenlib/BLI_math_color.h
@@ -32,10 +32,16 @@
 extern "C" {
 #endif
 
-#define BLI_CS_SMPTE	0
-#define BLI_CS_REC709	1
-#define BLI_CS_CIE		2
+/* primaries */
+#define BLI_XYZ_SMPTE	0
+#define BLI_XYZ_REC709_SRGB	1
+#define BLI_XYZ_CIE		2
 
+/* built-in profiles */
+#define BLI_PR_NONE		0
+#define BLI_PR_SRGB		1
+#define BLI_PR_REC709	2
+	
 /******************* Conversion to RGB ********************/
 
 void hsv_to_rgb(float h, float s, float v, float *r, float *g, float *b);
@@ -53,6 +59,16 @@ void rgb_to_hsv(float r, float g, float b, float *lh, float *ls, float *lv);
 unsigned int rgb_to_cpack(float r, float g, float b);
 unsigned int hsv_to_cpack(float h, float s, float v);
 
+/***************** Profile Transformations ********************/
+
+void gamma_correct(float *c, float gamma);
+float rec709_to_linearrgb(float c);
+float linearrgb_to_rec709(float c);
+float srgb_to_linearrgb(float c);
+float linearrgb_to_srgb(float c);
+void srgb_to_linearrgb_v3_v3(float *col_to, float *col_from);
+void linearrgb_to_srgb_v3_v3(float *col_to, float *col_from);
+	
 /************************** Other *************************/
 
 int constrain_rgb(float *r, float *g, float *b);
diff --git a/source/blender/blenlib/intern/math_color.c b/source/blender/blenlib/intern/math_color.c
index 7ae380a1dde..6dbd9c1381f 100644
--- a/source/blender/blenlib/intern/math_color.c
+++ b/source/blender/blenlib/intern/math_color.c
@@ -208,17 +208,17 @@ void rgb_to_hsv(float r, float g, float b, float *lh, float *ls, float *lv)
 void xyz_to_rgb(float xc, float yc, float zc, float *r, float *g, float *b, int colorspace)
 {
 	switch (colorspace) { 
-	case BLI_CS_SMPTE:
+	case BLI_XYZ_SMPTE:
 		*r = (3.50570f	 * xc) + (-1.73964f	 * yc) + (-0.544011f * zc);
 		*g = (-1.06906f	 * xc) + (1.97781f	 * yc) + (0.0351720f * zc);
 		*b = (0.0563117f * xc) + (-0.196994f * yc) + (1.05005f	 * zc);
 		break;
-	case BLI_CS_REC709:
+	case BLI_XYZ_REC709_SRGB:
 		*r = (3.240476f	 * xc) + (-1.537150f * yc) + (-0.498535f * zc);
 		*g = (-0.969256f * xc) + (1.875992f  * yc) + (0.041556f  * zc);
 		*b = (0.055648f	 * xc) + (-0.204043f * yc) + (1.057311f  * zc);
 		break;
-	case BLI_CS_CIE:
+	case BLI_XYZ_CIE:
 		*r = (2.28783848734076f	* xc) + (-0.833367677835217f	* yc) + (-0.454470795871421f	* zc);
 		*g = (-0.511651380743862f * xc) + (1.42275837632178f * yc) + (0.0888930017552939f * zc);
 		*b = (0.00572040983140966f	* xc) + (-0.0159068485104036f	* yc) + (1.0101864083734f	* zc);
@@ -274,6 +274,61 @@ void cpack_to_rgb(unsigned int col, float *r, float *g, float *b)
 	*b /= 255.0f;
 }
 
+/* ********************************* color transforms ********************************* */
+
+
+void gamma_correct(float *c, float gamma)
+{
+	*c = powf((*c), gamma);
+}
+
+float rec709_to_linearrgb(float c)
+{
+	if (c < 0.081f)
+		return (c < 0.0f)? 0.0f: c * (1.0f/4.5f);
+	else
+		return powf((c + 0.099f)*(1.0f/1.099f), (1.0f/0.45f));
+}
+
+float linearrgb_to_rec709(float c)
+{
+	if (c < 0.018f)
+		return (c < 0.0f)? 0.0f: c * 4.5f;
+	else
+		return 1.099f * powf(c, 0.45f) - 0.099f;
+}
+
+float srgb_to_linearrgb(float c)
+{
+	if (c < 0.04045f)
+		return (c < 0.0f)? 0.0f: c * (1.0f/12.92f);
+	else
+		return powf((c + 0.055f)*(1.0f/1.055f), 2.4f);
+}
+
+float linearrgb_to_srgb(float c)
+{
+	if (c < 0.0031308f)
+		return (c < 0.0f)? 0.0f: c * 12.92f;
+	else
+		return  1.055f * powf(c, 1.0f/2.4f) - 0.055f;
+}
+
+void srgb_to_linearrgb_v3_v3(float *col_to, float *col_from)
+{
+	col_to[0] = srgb_to_linearrgb(col_from[0]);
+	col_to[1] = srgb_to_linearrgb(col_from[1]);
+	col_to[2] = srgb_to_linearrgb(col_from[2]);
+}
+
+void linearrgb_to_srgb_v3_v3(float *col_to, float *col_from)
+{
+	col_to[0] = linearrgb_to_srgb(col_from[0]);
+	col_to[1] = linearrgb_to_srgb(col_from[1]);
+	col_to[2] = linearrgb_to_srgb(col_from[2]);
+}
+
+
 void minmax_rgb(short c[])
 {
 	if(c[0]>255) c[0]=255;
diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index ce760643b3d..6103c582da0 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -10064,7 +10064,7 @@ static void do_versions(FileData *fd, Library *lib, Main *main)
 		}
 	}
 
-	/* put 2.50 compatibility code here until next subversion bump */
+	if (main->versionfile < 250 || (main->versionfile == 250 && main->subversionfile < 8))
 	{
 		{
 			Scene *sce= main->scene.first;
@@ -10108,7 +10108,47 @@ static void do_versions(FileData *fd, Library *lib, Main *main)
 				ob=ob->id.next;
 			}
 		}
+		
+		/* only convert old 2.50 files with color management */
+		if (main->versionfile == 250) {
+			Scene *sce=main->scene.first;
+			Material *ma=main->mat.first;
+			World *wo=main->world.first;
+			int convert=0;
+			
+			/* convert to new color management system:
+			 while previously colors were stored as srgb, 
+			 now they are stored as linear internally, 
+			 with screen gamma correction in certain places in the UI. */
+
+			/* don't know what scene is active, so we'll convert if any scene has it enabled... */
+			while (sce) {
+				if(sce->r.color_mgt_flag & R_COLOR_MANAGEMENT)
+					convert=1;
+				sce=sce->id.next;
+			}
+			
+			if (convert) {
+				while(ma) {
+					srgb_to_linearrgb_v3_v3(&ma->r, &ma->r);
+					srgb_to_linearrgb_v3_v3(&ma->specr, &ma->specr);
+					srgb_to_linearrgb_v3_v3(&ma->mirr, &ma->mirr);
+					srgb_to_linearrgb_v3_v3(ma->sss_col, ma->sss_col);
+					ma=ma->id.next;
+				}
+				
+				while(wo) {
+					srgb_to_linearrgb_v3_v3(&wo->ambr, &wo->ambr);
+					srgb_to_linearrgb_v3_v3(&wo->horr, &wo->horr);
+					srgb_to_linearrgb_v3_v3(&wo->zenr, &wo->zenr);
+					wo=wo->id.next;
+				}
+			}
+		}
 	}
+	
+	/* put 2.50 compatibility code here until next subversion bump */
+	
 
 	/* 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/editors/interface/interface.c b/source/blender/editors/interface/interface.c
index 70bef5534a1..f0d09c505ac 100644
--- a/source/blender/editors/interface/interface.c
+++ b/source/blender/editors/interface/interface.c
@@ -1790,14 +1790,17 @@ uiBlock *uiBeginBlock(const bContext *C, ARegion *region, const char *name, shor
 {
 	uiBlock *block;
 	wmWindow *window;
+	Scene *scn;
 	int getsizex, getsizey;
 
 	window= CTX_wm_window(C);
+	scn = CTX_data_scene(C);
 
 	block= MEM_callocN(sizeof(uiBlock), "uiBlock");
 	block->active= 1;
 	block->dt= dt;
 	block->evil_C= (void*)C; // XXX
+	if (scn) block->color_profile= (scn->r.color_mgt_flag & R_COLOR_MANAGEMENT);
 	BLI_strncpy(block->name, name, sizeof(block->name));
 
 	if(region)
@@ -2295,6 +2298,7 @@ static uiBut *ui_def_but(uiBlock *block, int type, int retval, char *str, short
 	if(ELEM(but->type, HSVCUBE, HSVCIRCLE)) { /* hsv buttons temp storage */
 		float rgb[3];
 		ui_get_but_vectorf(but, rgb);
+
 		rgb_to_hsv(rgb[0], rgb[1], rgb[2], but->hsv, but->hsv+1, but->hsv+2);
 	}
 
diff --git a/source/blender/editors/interface/interface_draw.c b/source/blender/editors/interface/interface_draw.c
index 762ec541bff..e6e5cb198aa 100644
--- a/source/blender/editors/interface/interface_draw.c
+++ b/source/blender/editors/interface/interface_draw.c
@@ -736,6 +736,8 @@ void ui_draw_but_COLORBAND(uiBut *but, uiWidgetColors *wcol, rcti *rect)
 	for( a = 1; a < sizex; a++ ) {
 		pos = ((float)a) / (sizex-1);
 		do_colorband( coba, pos, colf );
+		if (but->block->color_profile != BLI_PR_NONE)
+			linearrgb_to_srgb_v3_v3(colf, colf);
 		
 		v1[0]=v2[0]= x1 + a;
 		
diff --git a/source/blender/editors/interface/interface_handlers.c b/source/blender/editors/interface/interface_handlers.c
index 6d65a2a57a1..a51824f10e9 100644
--- a/source/blender/editors/interface/interface_handlers.c
+++ b/source/blender/editors/interface/interface_handlers.c
@@ -2697,7 +2697,13 @@ static int ui_numedit_but_HSVCUBE(uiBut *but, uiHandleButtonData *data, int mx,
 {
 	float x, y;
 	int changed= 1;
-
+	int color_profile = but->block->color_profile;
+	
+	if (but->rnaprop) {
+		if (RNA_property_subtype(but->rnaprop) == PROP_COLOR_GAMMA)
+			color_profile = BLI_PR_NONE;
+	}
+		
 	/* relative position within box */
 	x= ((float)mx-but->x1)/(but->x2-but->x1);
 	y= ((float)my-but->y1)/(but->y2-but->y1);
@@ -2719,8 +2725,12 @@ static int ui_numedit_but_HSVCUBE(uiBut *but, uiHandleButtonData *data, int mx,
 	else if(but->a1==3) {
 		but->hsv[0]= x; 
 	}
-	else
+	else {
+		/* vertical 'value' strip */
 		but->hsv[2]= y; 
+		if (color_profile)
+			but->hsv[2] = srgb_to_linearrgb(but->hsv[2]);
+	}
 
 	ui_set_but_hsv(but);	// converts to rgb
 	
diff --git a/source/blender/editors/interface/interface_intern.h b/source/blender/editors/interface/interface_intern.h
index 21425bbb261..97ef1f1ea17 100644
--- a/source/blender/editors/interface/interface_intern.h
+++ b/source/blender/editors/interface/interface_intern.h
@@ -303,6 +303,8 @@ struct uiBlock {
 
 	int active;					// to keep blocks while drawing and free them afterwards
 	int puphash;				// popup menu hash for memory
+	
+	int color_profile;				// color profile for correcting linear colors for display
 
 	void *evil_C;				// XXX hack for dynamic operator enums
 };
diff --git a/source/blender/editors/interface/interface_layout.c b/source/blender/editors/interface/interface_layout.c
index d46cb4df1c0..175f1ff1e2a 100644
--- a/source/blender/editors/interface/interface_layout.c
+++ b/source/blender/editors/interface/interface_layout.c
@@ -409,10 +409,10 @@ static void ui_item_array(uiLayout *layout, uiBlock *block, char *name, int icon
 		}
 	}
 	else {
-		if(ELEM(subtype, PROP_COLOR, PROP_RGB))
+		if(ELEM(subtype, PROP_COLOR, PROP_COLOR_GAMMA))
 			uiDefAutoButR(block, ptr, prop, -1, "", 0, 0, 0, w, UI_UNIT_Y);
 
-		if(!ELEM(subtype, PROP_COLOR, PROP_RGB) || expand) {
+		if(!ELEM(subtype, PROP_COLOR, PROP_COLOR_GAMMA) || expand) {
 			/* layout for known array subtypes */
 			char str[3];
 
@@ -439,7 +439,7 @@ static void ui_item_array(uiLayout *layout, uiBlock *block, char *name, int icon
 					but->type= TOG;
 			}
 		}
-		else if(ELEM(subtype, PROP_COLOR, PROP_RGB) && len == 4) {
+		else if(ELEM(subtype, PROP_COLOR, PROP_COLOR_GAMMA) && len == 4) {
 			but= uiDefAutoButR(block, ptr, prop, 3, "A:", 0, 0, 0, w, UI_UNIT_Y);
 			if(slider && but->type==NUM)
 				but->type= NUMSLI;
diff --git a/source/blender/editors/interface/interface_regions.c b/source/blender/editors/interface/interface_regions.c
index c3eac3f3893..55b908a44ce 100644
--- a/source/blender/editors/interface/interface_regions.c
+++ b/source/blender/editors/interface/interface_regions.c
@@ -1902,9 +1902,16 @@ static void uiBlockPickerNew(uiBlock *block, float *col, float *hsv, float *old,
 	static short colormode= 0;	/* temp? 0=rgb, 1=hsv, 2=hex */
 	uiBut *bt;
 	int width;
+	static char tip[50];
 	
 	VECCOPY(old, col);	// old color stored there, for palette_cb to work
 	
+	/* existence of profile means storage is in linear colour space, with display correction */
+	if (block->color_profile == BLI_PR_NONE)
+		sprintf(tip, "Value in Display Color Space");
+	else
+		sprintf(tip, "Value in Linear RGB Color Space");
+	
 	/* HS circle */
 	bt= uiDefButF(block, HSVCIRCLE, retval, "",	0, 0,SPICK1,SPICK1, col, 0.0, 0.0, 0, 0, "");
 	uiButSetFunc(bt, do_picker_small_cb, bt, hsv);
@@ -1930,11 +1937,11 @@ static void uiBlockPickerNew(uiBlock *block, float *col, float *hsv, float *old,
 	sprintf(hexcol, "%02X%02X%02X", (unsigned int)(col[0]*255.0), (unsigned int)(col[1]*255.0), (unsigned int)(col[2]*255.0));	
 
 	uiBlockBeginAlign(block);
-	bt= uiDefButF(block, NUMSLI, 0, "R ",	0, -60, width, 19, col, 0.0, 1.0, 10, 3, "");
+	bt= uiDefButF(block, NUMSLI, 0, "R ",	0, -60, width, 19, col, 0.0, 1.0, 10, 3, tip);
 	uiButSetFunc(bt, do_palette1_cb, bt, hsv);
-	bt= uiDefButF(block, NUMSLI, 0, "G ",	0, -80, width, 19, col+1, 0.0, 1.0, 10, 3, "");
+	bt= uiDefButF(block, NUMSLI, 0, "G ",	0, -80, width, 19, col+1, 0.0, 1.0, 10, 3, tip);
 	uiButSetFunc(bt, do_palette1_cb, bt, hsv);
-	bt= uiDefButF(block, NUMSLI, 0, "B ",	0, -100, width, 19, col+2, 0.0, 1.0, 10, 3, "");
+	bt= uiDefButF(block, NUMSLI, 0, "B ",	0, -100, width, 19, col+2, 0.0, 1.0, 10, 3, tip);
 	uiButSetFunc(bt, do_palette1_cb, bt, hsv);
 	uiBlockEndAlign(block);
 
@@ -2000,6 +2007,13 @@ uiBlock *ui_block_func_COL(bContext *C, uiPopupBlockHandle *handle, void *arg_bu
 	
 	block= uiBeginBlock(C, handle->region, "colorpicker", UI_EMBOSS);
 	
+	/* XXX ideally the colour picker buttons would reference the rna property itself */
+	if (but->rnaprop) {
+		if (RNA_property_subtype(but->rnaprop) == PROP_COLOR_GAMMA) {
+			block->color_profile = BLI_PR_NONE;
+		}
+	}
+	
 	uiBlockSetFlag(block, UI_BLOCK_MOVEMOUSE_QUIT);
 	
 	VECCOPY(handle->retvec, but->editvec);
diff --git a/source/blender/editors/interface/interface_utils.c b/source/blender/editors/interface/interface_utils.c
index ecd8c9720c8..7aaa6cbb42b 100644
--- a/source/blender/editors/interface/interface_utils.c
+++ b/source/blender/editors/interface/interface_utils.c
@@ -80,7 +80,7 @@ uiBut *uiDefAutoButR(uiBlock *block, PointerRNA *ptr, PropertyRNA *prop, int ind
 		case PROP_INT:
 		case PROP_FLOAT:
 			if(arraylen && index == -1) {
-				if(RNA_property_subtype(prop) == PROP_COLOR)
+				if(ELEM(RNA_property_subtype(prop), PROP_COLOR, PROP_COLOR_GAMMA))
 					but= uiDefButR(block, COL, 0, name, x1, y1, x2, y2, ptr, propname, 0, 0, 0, -1, -1, NULL);
 			}
 			else if(RNA_property_subtype(prop) == PROP_PERCENTAGE || RNA_property_subtype(prop) == PROP_FACTOR)
diff --git a/source/blender/editors/interface/interface_widgets.c b/source/blender/editors/interface/interface_widgets.c
index e148fd9217f..4c9698974b4 100644
--- a/source/blender/editors/interface/interface_widgets.c
+++ b/source/blender/editors/interface/interface_widgets.c
@@ -44,6 +44,8 @@
 #include "BKE_global.h"
 #include "BKE_utildefines.h"
 
+#include "RNA_access.h"
+
 #include "BIF_gl.h"
 #include "BIF_glutil.h"
 
@@ -1693,6 +1695,17 @@ static void ui_draw_but_HSV_v(uiBut *but, rcti *rect)
 	uiWidgetBase wtb;
 	float rad= 0.5f*(rect->xmax - rect->xmin);
 	float x, y;
+	float v = but->hsv[2];
+	int color_profile = but->block->color_profile;
+	
+	if (but->rnaprop) {
+		if (RNA_property_subtype(but->rnaprop) == PROP_COLOR_GAMMA) {
+			color_profile = BLI_PR_NONE;
+		}
+	}
+
+	if (color_profile)
+		v = linearrgb_to_srgb(v);
 	
 	widget_init(&wtb);
 	
@@ -1709,8 +1722,8 @@ static void ui_draw_but_HSV_v(uiBut *but, rcti *rect)
 	widgetbase_draw(&wtb, &wcol_tmp);
 
 	/* cursor */
-	x= rect->xmin + 0.5f*(rect->xmax-rect->xmin);
-	y= rect->ymin + but->hsv[2]*(rect->ymax-rect->ymin);
+	x= rect->xmin + 0.5f * (rect->xmax-rect->xmin);
+	y= rect->ymin + v * (rect->ymax-rect->ymin);
 	CLAMP(y, rect->ymin+3.0, rect->ymax-3.0);
 	
 	ui_hsv_cursor(x, y);
@@ -2005,6 +2018,12 @@ static void widget_swatch(uiBut *but, uiWidgetColors *wcol, rcti *rect, int stat
 {
 	uiWidgetBase wtb;
 	float col[4];
+	int color_profile = but->block->color_profile;
+	
+	if (but->rnaprop) {
+		if (RNA_property_subtype(but->rnaprop) == PROP_COLOR_GAMMA)
+			color_profile = BLI_PR_NONE;
+	}
 	
 	widget_init(&wtb);
 	
@@ -2012,6 +2031,10 @@ static void widget_swatch(uiBut *but, uiWidgetColors *wcol, rcti *rect, int stat
 	round_box_edges(&wtb, roundboxalign, rect, 5.0f);
 		
 	ui_get_but_vectorf(but, col);
+	
+	if (color_profile)
+		linearrgb_to_srgb_v3_v3(col, col);
+	
 	wcol->inner[0]= FTOCHAR(col[0]);
 	wcol->inner[1]= FTOCHAR(col[1]);
 	wcol->inner[2]= FTOCHAR(col[2]);
diff --git a/source/blender/editors/space_view3d/drawmesh.c b/source/blender/editors/space_view3d/drawmesh.c
index bf73e70367c..51c7ba1a4bd 100644
--- a/source/blender/editors/space_view3d/drawmesh.c
+++ b/source/blender/editors/space_view3d/drawmesh.c
@@ -341,8 +341,9 @@ static int set_draw_settings_cached(int clearcache, int textured, MTFace *texfac
 struct TextureDrawState {
 	Object *ob;
 	int islit, istex;
+	int color_profile;
 	unsigned char obcol[4];
-} Gtexdraw = {NULL, 0, 0, {0, 0, 0, 0}};
+} Gtexdraw = {NULL, 0, 0, 0, {0, 0, 0, 0}};
 
 static void draw_textured_begin(Scene *scene, View3D *v3d, RegionView3D *rv3d, Object *ob)
 {
@@ -371,6 +372,7 @@ static void draw_textured_begin(Scene *scene, View3D *v3d, RegionView3D *rv3d, O
 
 	Gtexdraw.ob = ob;
 	Gtexdraw.istex = istex;
+	Gtexdraw.color_profile = scene->r.color_mgt_flag & R_COLOR_MANAGEMENT;
 	memcpy(Gtexdraw.obcol, obcol, sizeof(obcol));
 	set_draw_settings_cached(1, 0, 0, Gtexdraw.islit, 0, 0, 0);
 	glShadeModel(GL_SMOOTH);
@@ -413,7 +415,13 @@ static int draw_tface__set_draw_legacy(MTFace *tface, MCol *mcol, int matnr)
 		if (tface) glColor3f(1.0, 1.0, 1.0);
 		else {
 			Material *ma= give_current_material(Gtexdraw.ob, matnr+1);
-			if(ma) glColor3f(ma->r, ma->g, ma->b);
+			if(ma) {
+				float col[3];
+				if(Gtexdraw.color_profile) linearrgb_to_srgb_v3_v3(col, &ma->r);
+				else copy_v3_v3(col, &ma->r);
+				
+				glColor3fv(col);
+			}
 			else glColor3f(1.0, 1.0, 1.0);
 		}
 		return 2; /* Don't set color */
@@ -478,13 +486,19 @@ static void add_tface_color_layer(DerivedMesh *dm)
 				}
 			}
 			else {
+				float col[3];
 				Material *ma= give_current_material(Gtexdraw.ob, mface[i].mat_nr+1);
-				if(ma) 
+				
+				if(ma) {
+					if(Gtexdraw.color_profile) linearrgb_to_srgb_v3_v3(col, &ma->r);
+					else copy_v3_v3(col, &ma->r);
+					
 					for(j=0;j<4;j++) {
-						finalCol[i*4+j].b = ma->b;
-						finalCol[i*4+j].g = ma->g;
-						finalCol[i*4+j].r = ma->r;
+						finalCol[i*4+j].b = col[2];
+						finalCol[i*4+j].g = col[1];
+						finalCol[i*4+j].r = col[0];
 					}
+				}
 				else
 					for(j=0;j<4;j++) {
 						finalCol[i*4+j].b = 255;
diff --git a/source/blender/gpu/intern/gpu_draw.c b/source/blender/gpu/intern/gpu_draw.c
index 75e8073aafd..c2cf4dfa9fd 100644
--- a/source/blender/gpu/intern/gpu_draw.c
+++ b/source/blender/gpu/intern/gpu_draw.c
@@ -34,6 +34,8 @@
 
 #include "GL/glew.h"
 
+#include "BLI_math.h"
+
 #include "DNA_image_types.h"
 #include "DNA_lamp_types.h"
 #include "DNA_material_types.h"
@@ -856,6 +858,7 @@ void GPU_begin_object_materials(View3D *v3d, RegionView3D *rv3d, Scene *scene, O
 	GPUMaterial *gpumat;
 	GPUBlendMode blendmode;
 	int a;
+	int gamma = scene->r.color_mgt_flag & R_COLOR_MANAGEMENT;
 	
 	/* initialize state */
 	memset(&GMS, 0, sizeof(GMS));
@@ -930,6 +933,7 @@ void GPU_begin_object_materials(View3D *v3d, RegionView3D *rv3d, Scene *scene, O
 				GMS.matbuf[a][0][0]= ma->r;
 				GMS.matbuf[a][0][1]= ma->g;
 				GMS.matbuf[a][0][2]= ma->b;
+				if(gamma) linearrgb_to_srgb_v3_v3(&GMS.matbuf[a][0][0], &GMS.matbuf[a][0][0]);
 			} else {
 				GMS.matbuf[a][0][0]= (ma->ref+ma->emit)*ma->r;
 				GMS.matbuf[a][0][1]= (ma->ref+ma->emit)*ma->g;
@@ -939,6 +943,11 @@ void GPU_begin_object_materials(View3D *v3d, RegionView3D *rv3d, Scene *scene, O
 				GMS.matbuf[a][1][1]= ma->spec*ma->specg;
 				GMS.matbuf[a][1][2]= ma->spec*ma->specb;
 				GMS.matbuf[a][1][3]= 1.0;
+				
+				if(gamma) {
+					linearrgb_to_srgb_v3_v3(&GMS.matbuf[a][0][0], &GMS.matbuf[a][0][0]);
+					linearrgb_to_srgb_v3_v3(&GMS.matbuf[a][1][0], &GMS.matbuf[a][1][0]);
+				}
 			}
 
 			blendmode = (ma->alpha == 1.0f)? GPU_BLEND_SOLID: GPU_BLEND_ALPHA;
diff --git a/source/blender/makesrna/RNA_types.h b/source/blender/makesrna/RNA_types.h
index ff01f76fe71..27dd1069c1c 100644
--- a/source/blender/makesrna/RNA_types.h
+++ b/source/blender/makesrna/RNA_types.h
@@ -115,7 +115,7 @@ typedef enum PropertySubType {
 	PROP_QUATERNION = 27,
 	PROP_AXISANGLE = 28,
 	PROP_XYZ = 29,
-	PROP_RGB = 30,
+	PROP_COLOR_GAMMA = 30,
 
 	/* booleans */
 	PROP_LAYER = 40,
diff --git a/source/blender/makesrna/intern/makesrna.c b/source/blender/makesrna/intern/makesrna.c
index 3d4e128c3ac..543e1f3ecc0 100644
--- a/source/blender/makesrna/intern/makesrna.c
+++ b/source/blender/makesrna/intern/makesrna.c
@@ -1430,7 +1430,7 @@ static const char *rna_property_subtypename(PropertyType type)
 		case PROP_VELOCITY: return "PROP_VELOCITY";
 		case PROP_ACCELERATION: return "PROP_ACCELERATION";
 		case PROP_XYZ: return "PROP_XYZ";
-		case PROP_RGB: return "PROP_RGB";
+		case PROP_COLOR_GAMMA: return "PROP_COLOR_GAMMA";
 		case PROP_LAYER: return "PROP_LAYER";
 		case PROP_LAYER_MEMBER: return "PROP_LAYER_MEMBER";
 		default: {
diff --git a/source/blender/makesrna/intern/rna_access.c b/source/blender/makesrna/intern/rna_access.c
index 6c0a3c57f65..5ee811d4c46 100644
--- a/source/blender/makesrna/intern/rna_access.c
+++ b/source/blender/makesrna/intern/rna_access.c
@@ -693,7 +693,7 @@ char RNA_property_array_item_char(PropertyRNA *prop, int index)
 		return quatitem[index];
 	else if((index < 4) && ELEM6(subtype, PROP_TRANSLATION, PROP_DIRECTION, PROP_XYZ, PROP_EULER, PROP_VELOCITY, PROP_ACCELERATION))
 		return vectoritem[index];
-	else if ((index < 4) && ELEM(subtype, PROP_COLOR, PROP_RGB))
+	else if ((index < 4) && ELEM(subtype, PROP_COLOR, PROP_COLOR_GAMMA))
 		return coloritem[index];
 
 	return '\0';
@@ -731,7 +731,7 @@ int RNA_property_array_item_index(PropertyRNA *prop, char name)
 				return 3;
 		}
 	}
-	else if (ELEM(subtype, PROP_COLOR, PROP_RGB)) {
+	else if (ELEM(subtype, PROP_COLOR, PROP_COLOR_GAMMA)) {
 		switch (name) {
 			case 'R':
 				return 0;
diff --git a/source/blender/makesrna/intern/rna_brush.c b/source/blender/makesrna/intern/rna_brush.c
index e9744c7f5ed..28f546c07f1 100644
--- a/source/blender/makesrna/intern/rna_brush.c
+++ b/source/blender/makesrna/intern/rna_brush.c
@@ -203,7 +203,7 @@ static void rna_def_brush(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Rate", "Number of paints per second for Airbrush.");
 	RNA_def_property_update(prop, 0, "rna_Brush_update");
 	
-	prop= RNA_def_property(srna, "color", PROP_FLOAT, PROP_COLOR);
+	prop= RNA_def_property(srna, "color", PROP_FLOAT, PROP_COLOR_GAMMA);
 	RNA_def_property_float_sdna(prop, NULL, "rgb");
 	RNA_def_property_ui_text(prop, "Color", "");
 	RNA_def_property_update(prop, 0, "rna_Brush_update");
diff --git a/source/blender/makesrna/intern/rna_color.c b/source/blender/makesrna/intern/rna_color.c
index 2a97eb78382..c4edd00045b 100644
--- a/source/blender/makesrna/intern/rna_color.c
+++ b/source/blender/makesrna/intern/rna_color.c
@@ -216,13 +216,13 @@ static void rna_def_curvemapping(BlenderRNA *brna)
 	RNA_def_property_struct_type(prop, "CurveMap");
 	RNA_def_property_ui_text(prop, "Curves", "");
 
-	prop= RNA_def_property(srna, "black_level", PROP_FLOAT, PROP_RGB);
+	prop= RNA_def_property(srna, "black_level", PROP_FLOAT, PROP_COLOR);
 	RNA_def_property_float_sdna(prop, NULL, "black");
 	RNA_def_property_range(prop, -1000.0f, 1000.0f);
 	RNA_def_property_ui_text(prop, "Black Level", "For RGB curves, the color that black is mapped to");
 	RNA_def_property_float_funcs(prop, NULL, "rna_CurveMapping_black_level_set", NULL);
 
-	prop= RNA_def_property(srna, "white_level", PROP_FLOAT, PROP_RGB);
+	prop= RNA_def_property(srna, "white_level", PROP_FLOAT, PROP_COLOR);
 	RNA_def_property_float_sdna(prop, NULL, "white");
 	RNA_def_property_range(prop, -1000.0f, 1000.0f);
 	RNA_def_property_ui_text(prop, "White Level", "For RGB curves, the color that white is mapped to");
diff --git a/source/blender/makesrna/intern/rna_material.c b/source/blender/makesrna/intern/rna_material.c
index 5ff8bffe715..85007482dc4 100644
--- a/source/blender/makesrna/intern/rna_material.c
+++ b/source/blender/makesrna/intern/rna_material.c
@@ -1239,7 +1239,7 @@ static void rna_def_material_sss(BlenderRNA *brna)
 	RNA_def_struct_nested(brna, srna, "Material");
 	RNA_def_struct_ui_text(srna, "Material Subsurface Scattering", "Diffuse subsurface scattering settings for a Material datablock.");
 
-	prop= RNA_def_property(srna, "radius", PROP_FLOAT, PROP_RGB|PROP_UNIT_LENGTH);
+	prop= RNA_def_property(srna, "radius", PROP_FLOAT, PROP_COLOR|PROP_UNIT_LENGTH);
 	RNA_def_property_float_sdna(prop, NULL, "sss_radius");
 	RNA_def_property_range(prop, 0.001, FLT_MAX);
 	RNA_def_property_ui_range(prop, 0.001, 10000, 1, 3);
diff --git a/source/blender/makesrna/intern/rna_rna.c b/source/blender/makesrna/intern/rna_rna.c
index f8adb1a79d8..5997867030d 100644
--- a/source/blender/makesrna/intern/rna_rna.c
+++ b/source/blender/makesrna/intern/rna_rna.c
@@ -869,7 +869,7 @@ static void rna_def_property(BlenderRNA *brna)
 		{PROP_EULER, "EULER", 0, "Euler", ""},
 		{PROP_QUATERNION, "QUATERNION", 0, "Quaternion", ""},
 		{PROP_XYZ, "XYZ", 0, "XYZ", ""},
-		{PROP_RGB, "RGB", 0, "RGB", ""},
+		{PROP_COLOR_GAMMA, "COLOR_GAMMA", 0, "Gamma Corrected Color", ""},
 		{PROP_LAYER, "LAYER", 0, "Layer", ""},
 		{PROP_LAYER_MEMBER, "LAYER_MEMBERSHIP", 0, "Layer Membership", ""},
 		{0, NULL, 0, NULL, NULL}};
diff --git a/source/blender/render/intern/source/convertblender.c b/source/blender/render/intern/source/convertblender.c
index 32c2e18197f..8f8e083523b 100644
--- a/source/blender/render/intern/source/convertblender.c
+++ b/source/blender/render/intern/source/convertblender.c
@@ -4848,8 +4848,7 @@ void RE_Database_FromScene(Render *re, Scene *scene, int use_camera_view)
 	
 	/* still bad... doing all */
 	init_render_textures(re);
-	if (re->r.color_mgt_flag & R_COLOR_MANAGEMENT) color_manage_linearize(amb, &re->wrld.ambr);
-	else VECCOPY(amb, &re->wrld.ambr);
+	VECCOPY(amb, &re->wrld.ambr);
 	init_render_materials(re->r.mode, amb);
 	set_node_shader_lamp_loop(shade_material_loop);
 
@@ -5538,8 +5537,7 @@ void RE_Database_Baking(Render *re, Scene *scene, int type, Object *actob)
 	/* still bad... doing all */
 	init_render_textures(re);
 	
-	if (re->r.color_mgt_flag & R_COLOR_MANAGEMENT) color_manage_linearize(amb, &re->wrld.ambr);
-	else VECCOPY(amb, &re->wrld.ambr);
+	VECCOPY(amb, &re->wrld.ambr);
 	init_render_materials(re->r.mode, amb);
 	
 	set_node_shader_lamp_loop(shade_material_loop);
diff --git a/source/blender/render/intern/source/pixelshading.c b/source/blender/render/intern/source/pixelshading.c
index d4b7c403f50..6fef8279c7e 100644
--- a/source/blender/render/intern/source/pixelshading.c
+++ b/source/blender/render/intern/source/pixelshading.c
@@ -537,15 +537,9 @@ void shadeSkyView(float *colf, float *rco, float *view, float *dxyview, short th
 		/* the fraction of how far we are above the bottom of the screen */
 		blend= fabs(0.5+ view[1]);
 	}
-	
-	if (R.r.color_mgt_flag & R_COLOR_MANAGEMENT) {
-		color_manage_linearize(hor, &R.wrld.horr);
-		color_manage_linearize(zen, &R.wrld.zenr);
-	}
-	else {
-		VECCOPY(hor, &R.wrld.horr);
-		VECCOPY(zen, &R.wrld.zenr);
-	}
+
+	VECCOPY(hor, &R.wrld.horr);
+	VECCOPY(zen, &R.wrld.zenr);
 
 	/* Careful: SKYTEX and SKYBLEND are NOT mutually exclusive! If           */
 	/* SKYBLEND is active, the texture and color blend are added.           */
@@ -633,10 +627,7 @@ void shadeSkyPixel(float *collector, float fx, float fy, short thread)
 	} 
 	else if((R.wrld.skytype & (WO_SKYBLEND+WO_SKYTEX))==0) {
 		/* 2. solid color */
-		if(R.r.color_mgt_flag & R_COLOR_MANAGEMENT)
-			color_manage_linearize(collector, &R.wrld.horr);
-		else
-			VECCOPY(collector, &R.wrld.horr);
+		VECCOPY(collector, &R.wrld.horr);
 
 		collector[3] = 0.0f;
 	} 
diff --git a/source/blender/render/intern/source/shadeinput.c b/source/blender/render/intern/source/shadeinput.c
index 396c713cfb7..fd1e27ab28a 100644
--- a/source/blender/render/intern/source/shadeinput.c
+++ b/source/blender/render/intern/source/shadeinput.c
@@ -91,42 +91,16 @@ extern struct Render R;
  * doing inverse gamma correction where applicable */
 void shade_input_init_material(ShadeInput *shi)
 {
-	if (R.r.color_mgt_flag & R_COLOR_MANAGEMENT) {
-		color_manage_linearize(&shi->r, &shi->mat->r);
-		color_manage_linearize(&shi->specr, &shi->mat->specr);
-		color_manage_linearize(&shi->mirr, &shi->mat->mirr);
-		
-		/* material ambr / ambg / ambb is overwritten from world
-		color_manage_linearize(shi->ambr, shi->mat->ambr);
-		*/
-		
-		/* note, keep this synced with render_types.h */
-		memcpy(&shi->amb, &shi->mat->amb, 11*sizeof(float));
-		shi->har= shi->mat->har;
-	} else {
-		/* note, keep this synced with render_types.h */
-		memcpy(&shi->r, &shi->mat->r, 23*sizeof(float));
-		shi->har= shi->mat->har;
-	}
-
-}
-
-static void shadeinput_colors_linearize(ShadeInput *shi)
-{
-	color_manage_linearize(&shi->r, &shi->r);
-	color_manage_linearize(&shi->specr, &shi->specr);
-	color_manage_linearize(&shi->mirr, &shi->mirr);
+	/* note, keep this synced with render_types.h */
+	memcpy(&shi->r, &shi->mat->r, 23*sizeof(float));
+	shi->har= shi->mat->har;
 }
 
 /* also used as callback for nodes */
 /* delivers a fully filled in ShadeResult, for all passes */
 void shade_material_loop(ShadeInput *shi, ShadeResult *shr)
 {
-	/* because node materials don't have access to rendering context,
-	 * inverse gamma correction must happen here. evil. */
-	if (R.r.color_mgt_flag & R_COLOR_MANAGEMENT && shi->nodes == 1)
-		shadeinput_colors_linearize(shi);
-	
+
 	shade_lamp_loop(shi, shr);	/* clears shr */
 	
 	if(shi->translucency!=0.0f) {
@@ -626,7 +600,7 @@ void shade_input_set_strand_texco(ShadeInput *shi, StrandRen *strand, StrandVert
 	
 	if (R.r.color_mgt_flag & R_COLOR_MANAGEMENT) {
 		if(mode & (MA_VERTEXCOL|MA_VERTEXCOLP|MA_FACETEXTURE)) {
-			color_manage_linearize(shi->vcol, shi->vcol);
+			srgb_to_linearrgb_v3_v3(shi->vcol, shi->vcol);
 		}
 	}
 	
@@ -1291,7 +1265,7 @@ void shade_input_set_shade_texco(ShadeInput *shi)
 	*/
 	if (R.r.color_mgt_flag & R_COLOR_MANAGEMENT) {
 		if(mode & (MA_VERTEXCOL|MA_VERTEXCOLP|MA_FACETEXTURE)) {
-			color_manage_linearize(shi->vcol, shi->vcol);
+			srgb_to_linearrgb_v3_v3(shi->vcol, shi->vcol);
 		}
 	}
 	
diff --git a/source/blender/render/intern/source/sss.c b/source/blender/render/intern/source/sss.c
index 25cfc0f1253..e551cf0f3d2 100644
--- a/source/blender/render/intern/source/sss.c
+++ b/source/blender/render/intern/source/sss.c
@@ -926,20 +926,17 @@ static void sss_create_tree_mat(Render *re, Material *mat)
 	if(!re->test_break(re->tbh)) {
 		SSSData *sss= MEM_callocN(sizeof(*sss), "SSSData");
 		float ior= mat->sss_ior, cfac= mat->sss_colfac;
-		float col[3], *radius= mat->sss_radius;
+		float *radius= mat->sss_radius;
 		float fw= mat->sss_front, bw= mat->sss_back;
 		float error = mat->sss_error;
 
 		error= get_render_aosss_error(&re->r, error);
 		if((re->r.scemode & R_PREVIEWBUTS) && error < 0.5f)
 			error= 0.5f;
-
-		if (re->r.color_mgt_flag & R_COLOR_MANAGEMENT) color_manage_linearize(col, mat->sss_col);
-		else VECCOPY(col, mat->sss_col);
 		
-		sss->ss[0]= scatter_settings_new(col[0], radius[0], ior, cfac, fw, bw);
-		sss->ss[1]= scatter_settings_new(col[1], radius[1], ior, cfac, fw, bw);
-		sss->ss[2]= scatter_settings_new(col[2], radius[2], ior, cfac, fw, bw);
+		sss->ss[0]= scatter_settings_new(mat->sss_col[0], radius[0], ior, cfac, fw, bw);
+		sss->ss[1]= scatter_settings_new(mat->sss_col[1], radius[1], ior, cfac, fw, bw);
+		sss->ss[2]= scatter_settings_new(mat->sss_col[2], radius[2], ior, cfac, fw, bw);
 		sss->tree= scatter_tree_new(sss->ss, mat->sss_scale, error,
 			co, color, area, totpoint);
 
diff --git a/source/blender/render/intern/source/texture.c b/source/blender/render/intern/source/texture.c
index a9f6e7a53fd..16372d7a15d 100644
--- a/source/blender/render/intern/source/texture.c
+++ b/source/blender/render/intern/source/texture.c
@@ -2051,8 +2051,13 @@ void do_material_tex(ShadeInput *shi)
 				else texres.tin= texres.ta;
 				
 				/* inverse gamma correction */
-				if (R.r.color_mgt_flag & R_COLOR_MANAGEMENT) {
-					color_manage_linearize(tcol, tcol);
+				if (tex->type==TEX_IMAGE) {
+					Image *ima = tex->ima;
+					ImBuf *ibuf = BKE_image_get_ibuf(ima, &tex->iuser);
+					
+					/* don't linearize float buffers, assumed to be linear */
+					if (ibuf && !(ibuf->rect_float) && R.r.color_mgt_flag & R_COLOR_MANAGEMENT)
+						srgb_to_linearrgb_v3_v3(tcol, tcol);
 				}
 				
 				if(mtex->mapto & MAP_COL) {
@@ -2404,11 +2409,6 @@ void do_volume_tex(ShadeInput *shi, float *xyz, int mapto_flag, float *col, floa
 						texres.tin= texres.ta;
 				}
 				
-				/* inverse gamma correction */
-				if (R.r.color_mgt_flag & R_COLOR_MANAGEMENT) {
-					color_manage_linearize(tcol, tcol);
-				}
-				
 				/* used for emit */
 				if((mapto_flag & MAP_EMISSION_COL) && (mtex->mapto & MAP_EMISSION_COL)) {
 					float colemitfac= mtex->colemitfac*stencilTin;
@@ -2556,8 +2556,13 @@ void do_halo_tex(HaloRen *har, float xn, float yn, float *colf)
 		else texres.tin= texres.ta;
 
 		/* inverse gamma correction */
-		if (R.r.color_mgt_flag & R_COLOR_MANAGEMENT) {
-			color_manage_linearize(&texres.tr, &texres.tr);
+		if (mtex->tex->type==TEX_IMAGE) {
+			Image *ima = mtex->tex->ima;
+			ImBuf *ibuf = BKE_image_get_ibuf(ima, &mtex->tex->iuser);
+			
+			/* don't linearize float buffers, assumed to be linear */
+			if (ibuf && !(ibuf->rect_float) && R.r.color_mgt_flag & R_COLOR_MANAGEMENT)
+				srgb_to_linearrgb_v3_v3(&texres.tr, &texres.tr);
 		}
 
 		fact= texres.tin*mtex->colfac;
@@ -2605,6 +2610,7 @@ void do_halo_tex(HaloRen *har, float xn, float yn, float *colf)
 void do_sky_tex(float *rco, float *lo, float *dxyview, float *hor, float *zen, float *blend, int skyflag, short thread)
 {
 	MTex *mtex;
+	Tex *tex;
 	TexResult texres= {0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0, NULL};
 	float *co, fact, stencilTin=1.0;
 	float tempvec[3], texvec[3], dxt[3], dyt[3];
@@ -2618,7 +2624,8 @@ void do_sky_tex(float *rco, float *lo, float *dxyview, float *hor, float *zen, f
 		if(R.wrld.mtex[tex_nr]) {
 			mtex= R.wrld.mtex[tex_nr];
 			
-			if(mtex->tex==0) continue;
+			tex= mtex->tex;
+			if(tex==0) continue;
 			/* if(mtex->mapto==0) continue; */
 			
 			/* which coords */
@@ -2700,7 +2707,7 @@ void do_sky_tex(float *rco, float *lo, float *dxyview, float *hor, float *zen, f
 			else texvec[2]= mtex->size[2]*(mtex->ofs[2]);
 			
 			/* texture */
-			if(mtex->tex->type==TEX_IMAGE) do_2d_mapping(mtex, texvec, NULL, NULL, dxt, dyt);
+			if(tex->type==TEX_IMAGE) do_2d_mapping(mtex, texvec, NULL, NULL, dxt, dyt);
 		
 			rgb= multitex(mtex->tex, texvec, dxt, dyt, R.osa, &texres, thread, mtex->which_output);
 			
@@ -2748,8 +2755,13 @@ void do_sky_tex(float *rco, float *lo, float *dxyview, float *hor, float *zen, f
 				tcol[0]= texres.tr; tcol[1]= texres.tg; tcol[2]= texres.tb;
 
 				/* inverse gamma correction */
-				if (R.r.color_mgt_flag & R_COLOR_MANAGEMENT) {
-					color_manage_linearize(tcol, tcol);
+				if (tex->type==TEX_IMAGE) {
+					Image *ima = tex->ima;
+					ImBuf *ibuf = BKE_image_get_ibuf(ima, &tex->iuser);
+					
+					/* don't linearize float buffers, assumed to be linear */
+					if (ibuf && !(ibuf->rect_float) && R.r.color_mgt_flag & R_COLOR_MANAGEMENT)
+						srgb_to_linearrgb_v3_v3(tcol, tcol);
 				}
 
 				if(mtex->mapto & WOMAP_HORIZ) {
@@ -2947,8 +2959,13 @@ void do_lamp_tex(LampRen *la, float *lavec, ShadeInput *shi, float *colf, int ef
 				else texres.tin= texres.ta;
 
 				/* inverse gamma correction */
-				if (R.r.color_mgt_flag & R_COLOR_MANAGEMENT) {
-					color_manage_linearize(&texres.tr, &texres.tr);
+				if (tex->type==TEX_IMAGE) {
+					Image *ima = tex->ima;
+					ImBuf *ibuf = BKE_image_get_ibuf(ima, &tex->iuser);
+					
+					/* don't linearize float buffers, assumed to be linear */
+					if (ibuf && !(ibuf->rect_float) && R.r.color_mgt_flag & R_COLOR_MANAGEMENT)
+						srgb_to_linearrgb_v3_v3(&texres.tr, &texres.tr);
 				}
 
 				/* lamp colors were premultiplied with this */