D2607: Switch eye dropper to use linear color space internally

This switches the internal color representation of the eye dropper from display space to linear. Any time a linear color is requested and the color is picked from a linear object, the result is now precise to the bit as the color gets patched through directly. Color space conversion now only happens when a color is picked from non-linear display space objects or when the color is requested to be returned in non-linear space.

In addition, this patch changes the DifferenceMatte node to interpret a tolerance of 0.0 to accept colors that are identical bit by bit, as apposed to simply refusing all colors.

8 files changed, 23 insertions, 37 deletions

diff --git a/source/blender/compositor/operations/COM_DifferenceMatteOperation.cpp b/source/blender/compositor/operations/COM_DifferenceMatteOperation.cpp
index 325ef83a529..aa58c0571cf 100644
--- a/source/blender/compositor/operations/COM_DifferenceMatteOperation.cpp
+++ b/source/blender/compositor/operations/COM_DifferenceMatteOperation.cpp
@@ -65,11 +65,11 @@ void DifferenceMatteOperation::executePixelSampled(float output[4], float x, flo
 	difference = difference / 3.0f;
 
 	/* make 100% transparent */
-	if (difference < tolerance) {
+	if (difference <= tolerance) {
 		output[0] = 0.0f;
 	}
 	/*in the falloff region, make partially transparent */
-	else if (difference < falloff + tolerance) {
+	else if (difference <= falloff + tolerance) {
 		difference = difference - tolerance;
 		alpha = difference / falloff;
 		/*only change if more transparent than before */
diff --git a/source/blender/editors/include/ED_clip.h b/source/blender/editors/include/ED_clip.h
index 5f8ebd87d19..91f8b39f7b9 100644
--- a/source/blender/editors/include/ED_clip.h
+++ b/source/blender/editors/include/ED_clip.h
@@ -63,7 +63,7 @@ int ED_space_clip_get_clip_frame_number(struct SpaceClip *sc);
 struct ImBuf *ED_space_clip_get_buffer(struct SpaceClip *sc);
 struct ImBuf *ED_space_clip_get_stable_buffer(struct SpaceClip *sc, float loc[2], float *scale, float *angle);
 
-bool ED_space_clip_color_sample(struct Scene *scene, struct SpaceClip *sc, struct ARegion *ar, int mval[2], float r_col[3]);
+bool ED_space_clip_color_sample(struct SpaceClip *sc, struct ARegion *ar, int mval[2], float r_col[3]);
 
 void ED_clip_update_frame(const struct Main *mainp, int cfra);
 bool ED_clip_view_selection(const struct bContext *C, struct ARegion *ar, bool fit);
diff --git a/source/blender/editors/include/ED_image.h b/source/blender/editors/include/ED_image.h
index 283113f93d6..9de550a20ce 100644
--- a/source/blender/editors/include/ED_image.h
+++ b/source/blender/editors/include/ED_image.h
@@ -46,7 +46,7 @@ void          ED_space_image_set(struct SpaceImage *sima, struct Scene *scene, s
 struct Mask  *ED_space_image_get_mask(struct SpaceImage *sima);
 void          ED_space_image_set_mask(struct bContext *C, struct SpaceImage *sima, struct Mask *mask);
 
-bool ED_space_image_color_sample(struct Scene *scene, struct SpaceImage *sima, struct ARegion *ar, int mval[2], float r_col[3]);
+bool ED_space_image_color_sample(struct SpaceImage *sima, struct ARegion *ar, int mval[2], float r_col[3]);
 struct ImBuf *ED_space_image_acquire_buffer(struct SpaceImage *sima, void **r_lock);
 void ED_space_image_release_buffer(struct SpaceImage *sima, struct ImBuf *ibuf, void *lock);
 bool ED_space_image_has_buffer(struct SpaceImage *sima);
diff --git a/source/blender/editors/include/ED_node.h b/source/blender/editors/include/ED_node.h
index f7b9d6b4f9e..e3c382382a9 100644
--- a/source/blender/editors/include/ED_node.h
+++ b/source/blender/editors/include/ED_node.h
@@ -107,7 +107,7 @@ void ED_node_composite_job(const struct bContext *C, struct bNodeTree *nodetree,
 void ED_operatormacros_node(void);
 
 /* node_view.c */
-bool ED_space_node_color_sample(struct Scene *scene, struct SpaceNode *snode, struct ARegion *ar, int mval[2], float r_col[3]);
+bool ED_space_node_color_sample(struct SpaceNode *snode, struct ARegion *ar, int mval[2], float r_col[3]);
 
 #endif /* __ED_NODE_H__ */
 
diff --git a/source/blender/editors/interface/interface_eyedropper.c b/source/blender/editors/interface/interface_eyedropper.c
index f3859154dfb..eab609ebe84 100644
--- a/source/blender/editors/interface/interface_eyedropper.c
+++ b/source/blender/editors/interface/interface_eyedropper.c
@@ -225,7 +225,7 @@ static bool eyedropper_init(bContext *C, wmOperator *op)
 		return false;
 	}
 
-	if (RNA_property_subtype(eye->prop) == PROP_COLOR) {
+	if (RNA_property_subtype(eye->prop) != PROP_COLOR) {
 		const char *display_device;
 		float col[4];
 
@@ -235,7 +235,7 @@ static bool eyedropper_init(bContext *C, wmOperator *op)
 		/* store inital color */
 		RNA_property_float_get_array(&eye->ptr, eye->prop, col);
 		if (eye->display) {
-			IMB_colormanagement_scene_linear_to_display_v3(col, eye->display);
+			IMB_colormanagement_display_to_scene_linear_v3(col, eye->display);
 		}
 		copy_v3_v3(eye->init_col, col);
 	}
@@ -266,6 +266,8 @@ static void eyedropper_color_sample_fl(bContext *C, Eyedropper *UNUSED(eye), int
 	/* we could use some clever */
 	wmWindow *win = CTX_wm_window(C);
 	ScrArea *sa = BKE_screen_find_area_xy(win->screen, SPACE_TYPE_ANY, mx, my);
+	const char *display_device = CTX_data_scene(C)->display_settings.display_device;
+	struct ColorManagedDisplay *display = IMB_colormanagement_display_get_named(display_device);
 
 	if (sa) {
 		if (sa->spacetype == SPACE_IMAGE) {
@@ -275,7 +277,7 @@ static void eyedropper_color_sample_fl(bContext *C, Eyedropper *UNUSED(eye), int
 				int mval[2] = {mx - ar->winrct.xmin,
 				               my - ar->winrct.ymin};
 
-				if (ED_space_image_color_sample(CTX_data_scene(C), sima, ar, mval, r_col)) {
+				if (ED_space_image_color_sample(sima, ar, mval, r_col)) {
 					return;
 				}
 			}
@@ -287,7 +289,7 @@ static void eyedropper_color_sample_fl(bContext *C, Eyedropper *UNUSED(eye), int
 				int mval[2] = {mx - ar->winrct.xmin,
 				               my - ar->winrct.ymin};
 
-				if (ED_space_node_color_sample(CTX_data_scene(C), snode, ar, mval, r_col)) {
+				if (ED_space_node_color_sample(snode, ar, mval, r_col)) {
 					return;
 				}
 			}
@@ -299,7 +301,7 @@ static void eyedropper_color_sample_fl(bContext *C, Eyedropper *UNUSED(eye), int
 				int mval[2] = {mx - ar->winrct.xmin,
 				               my - ar->winrct.ymin};
 
-				if (ED_space_clip_color_sample(CTX_data_scene(C), sc, ar, mval, r_col)) {
+				if (ED_space_clip_color_sample(sc, ar, mval, r_col)) {
 					return;
 				}
 			}
@@ -310,6 +312,8 @@ static void eyedropper_color_sample_fl(bContext *C, Eyedropper *UNUSED(eye), int
 	glReadBuffer(GL_FRONT);
 	glReadPixels(mx, my, 1, 1, GL_RGB, GL_FLOAT, r_col);
 	glReadBuffer(GL_BACK);
+	
+	IMB_colormanagement_display_to_scene_linear_v3(r_col, display);
 }
 
 /* sets the sample color RGB, maintaining A */
@@ -320,10 +324,10 @@ static void eyedropper_color_set(bContext *C, Eyedropper *eye, const float col[3
 	/* to maintain alpha */
 	RNA_property_float_get_array(&eye->ptr, eye->prop, col_conv);
 
-	/* convert from display space to linear rgb space */
+	/* convert from linear rgb space to display space */
 	if (eye->display) {
 		copy_v3_v3(col_conv, col);
-		IMB_colormanagement_display_to_scene_linear_v3(col_conv, eye->display);
+		IMB_colormanagement_scene_linear_to_display_v3(col_conv, eye->display);
 	}
 	else {
 		copy_v3_v3(col_conv, col);
diff --git a/source/blender/editors/space_clip/clip_editor.c b/source/blender/editors/space_clip/clip_editor.c
index 14d0f909d23..59dd755173f 100644
--- a/source/blender/editors/space_clip/clip_editor.c
+++ b/source/blender/editors/space_clip/clip_editor.c
@@ -259,11 +259,9 @@ ImBuf *ED_space_clip_get_stable_buffer(SpaceClip *sc, float loc[2], float *scale
 	return NULL;
 }
 
-/* Returns color in the display space, matching ED_space_image_color_sample(). */
-bool ED_space_clip_color_sample(Scene *scene, SpaceClip *sc, ARegion *ar, int mval[2], float r_col[3])
+/* Returns color in linear space, matching ED_space_image_color_sample(). */
+bool ED_space_clip_color_sample(SpaceClip *sc, ARegion *ar, int mval[2], float r_col[3])
 {
-	const char *display_device = scene->display_settings.display_device;
-	struct ColorManagedDisplay *display = IMB_colormanagement_display_get_named(display_device);
 	ImBuf *ibuf;
 	float fx, fy, co[2];
 	bool ret = false;
@@ -299,11 +297,7 @@ bool ED_space_clip_color_sample(Scene *scene, SpaceClip *sc, ARegion *ar, int mv
 			ret = true;
 		}
 	}
-
-	if (ret) {
-		IMB_colormanagement_scene_linear_to_display_v3(r_col, display);
-	}
-
+	
 	IMB_freeImBuf(ibuf);
 
 	return ret;
diff --git a/source/blender/editors/space_image/image_ops.c b/source/blender/editors/space_image/image_ops.c
index 324a3cb13b7..d00ebed5bcc 100644
--- a/source/blender/editors/space_image/image_ops.c
+++ b/source/blender/editors/space_image/image_ops.c
@@ -2900,11 +2900,9 @@ static void image_sample_draw(const bContext *C, ARegion *ar, void *arg_info)
 	}
 }
 
-/* Returns color in the display space, matching ED_space_node_color_sample(). */
-bool ED_space_image_color_sample(Scene *scene, SpaceImage *sima, ARegion *ar, int mval[2], float r_col[3])
+/* Returns color in linear space, matching ED_space_node_color_sample(). */
+bool ED_space_image_color_sample(SpaceImage *sima, ARegion *ar, int mval[2], float r_col[3])
 {
-	const char *display_device = scene->display_settings.display_device;
-	struct ColorManagedDisplay *display = IMB_colormanagement_display_get_named(display_device);
 	void *lock;
 	ImBuf *ibuf = ED_space_image_acquire_buffer(sima, &lock);
 	float fx, fy;
@@ -2938,10 +2936,6 @@ bool ED_space_image_color_sample(Scene *scene, SpaceImage *sima, ARegion *ar, in
 		}
 	}
 
-	if (ret) {
-		IMB_colormanagement_scene_linear_to_display_v3(r_col, display);
-	}
-
 	ED_space_image_release_buffer(sima, ibuf, lock);
 	return ret;
 }
diff --git a/source/blender/editors/space_node/node_view.c b/source/blender/editors/space_node/node_view.c
index 80934e7d0a0..9c73af12e3f 100644
--- a/source/blender/editors/space_node/node_view.c
+++ b/source/blender/editors/space_node/node_view.c
@@ -417,13 +417,11 @@ static void sample_draw(const bContext *C, ARegion *ar, void *arg_info)
 	}
 }
 
-/* Returns color in the display space, matching ED_space_image_color_sample().
+/* Returns color in linear space, matching ED_space_image_color_sample().
  * And here we've got recursion in the comments tips...
  */
-bool ED_space_node_color_sample(Scene *scene, SpaceNode *snode, ARegion *ar, int mval[2], float r_col[3])
+bool ED_space_node_color_sample(SpaceNode *snode, ARegion *ar, int mval[2], float r_col[3])
 {
-	const char *display_device = scene->display_settings.display_device;
-	struct ColorManagedDisplay *display = IMB_colormanagement_display_get_named(display_device);
 	void *lock;
 	Image *ima;
 	ImBuf *ibuf;
@@ -471,10 +469,6 @@ bool ED_space_node_color_sample(Scene *scene, SpaceNode *snode, ARegion *ar, int
 		}
 	}
 
-	if (ret) {
-		IMB_colormanagement_scene_linear_to_display_v3(r_col, display);
-	}
-
 	BKE_image_release_ibuf(ima, ibuf, lock);
 
 	return ret;