Color Management: support different settings for render and compositing output

The Output Properties > Output panel now has a Color Management subpanel to
override scene settings. When set to Override instead of Follow Scene, there
are settings to:

* For OpenEXR, choose a (linear) colorspace for RGBA passes
* For other file formats, use different display/view/look/exposure/gamma

These settings affect animation render output, image save of renders and the
compositor file output node. Additionally, the image save operator and
compositor file output nodes also support overriding color management.

Includes some layout changes to the relevant panels to accomdate the new
settings and to improve consistency. Ideally subpanels would be used to better
organize these settings, however nodes and operators don't currently support
creating subpanels.

Differential Revision: https://developer.blender.org/D14402

2 files changed, 36 insertions, 3 deletions

diff --git a/source/blender/imbuf/IMB_colormanagement.h b/source/blender/imbuf/IMB_colormanagement.h
index a336cc1770a..7cf2c02e657 100644
--- a/source/blender/imbuf/IMB_colormanagement.h
+++ b/source/blender/imbuf/IMB_colormanagement.h
@@ -53,6 +53,7 @@ bool IMB_colormanagement_space_is_data(struct ColorSpace *colorspace);
 bool IMB_colormanagement_space_is_scene_linear(struct ColorSpace *colorspace);
 bool IMB_colormanagement_space_is_srgb(struct ColorSpace *colorspace);
 bool IMB_colormanagement_space_name_is_data(const char *name);
+bool IMB_colormanagement_space_name_is_scene_linear(const char *name);
 
 /**
  * Convert a float RGB triplet to the correct luminance weighted average.
diff --git a/source/blender/imbuf/intern/colormanagement.c b/source/blender/imbuf/intern/colormanagement.c
index 8624a7866b6..15a586ea762 100644
--- a/source/blender/imbuf/intern/colormanagement.c
+++ b/source/blender/imbuf/intern/colormanagement.c
@@ -1394,6 +1394,12 @@ bool IMB_colormanagement_space_name_is_data(const char *name)
   return (colorspace && colorspace->is_data);
 }
 
+bool IMB_colormanagement_space_name_is_scene_linear(const char *name)
+{
+  ColorSpace *colorspace = colormanage_colorspace_get_named(name);
+  return (colorspace && IMB_colormanagement_space_is_scene_linear(colorspace));
+}
+
 const float *IMB_colormanagement_get_xyz_to_rgb()
 {
   return &imbuf_xyz_to_rgb[0][0];
@@ -2444,9 +2450,13 @@ ImBuf *IMB_colormanagement_imbuf_for_write(ImBuf *ibuf,
     ibuf->userflags &= ~(IB_RECT_INVALID | IB_DISPLAY_BUFFER_INVALID);
   }
 
-  const bool do_colormanagement = save_as_render && (is_movie || !requires_linear_float);
+  const bool do_colormanagement_display = save_as_render && (is_movie || !requires_linear_float);
+  const bool do_colormanagement_linear = save_as_render && requires_linear_float &&
+                                         imf->linear_colorspace_settings.name[0] &&
+                                         !IMB_colormanagement_space_name_is_scene_linear(
+                                             imf->linear_colorspace_settings.name);
 
-  if (do_colormanagement || do_alpha_under) {
+  if (do_colormanagement_display || do_colormanagement_linear || do_alpha_under) {
     if (allocate_result) {
       colormanaged_ibuf = IMB_dupImBuf(ibuf);
     }
@@ -2499,7 +2509,8 @@ ImBuf *IMB_colormanagement_imbuf_for_write(ImBuf *ibuf,
     }
   }
 
-  if (do_colormanagement) {
+  if (do_colormanagement_display) {
+    /* Color management with display and view transform. */
     bool make_byte = false;
 
     /* for proper check whether byte buffer is required by a format or not
@@ -2532,6 +2543,27 @@ ImBuf *IMB_colormanagement_imbuf_for_write(ImBuf *ibuf,
           &imf->view_settings, &imf->display_settings);
     }
   }
+  else if (do_colormanagement_linear) {
+    /* Color management transform to another linear color space. */
+    if (!colormanaged_ibuf->rect_float) {
+      IMB_float_from_rect(colormanaged_ibuf);
+      imb_freerectImBuf(colormanaged_ibuf);
+    }
+
+    if (colormanaged_ibuf->rect_float) {
+      const char *from_colorspace = (ibuf->float_colorspace) ? ibuf->float_colorspace->name :
+                                                               global_role_scene_linear;
+      const char *to_colorspace = imf->linear_colorspace_settings.name;
+
+      IMB_colormanagement_transform(colormanaged_ibuf->rect_float,
+                                    colormanaged_ibuf->x,
+                                    colormanaged_ibuf->y,
+                                    colormanaged_ibuf->channels,
+                                    from_colorspace,
+                                    to_colorspace,
+                                    false);
+    }
+  }
 
   if (colormanaged_ibuf != ibuf) {
     IMB_metadata_copy(colormanaged_ibuf, ibuf);