[Bf-blender-cvs] [ecc7a837982] master: UI: Object Thumbnails Orientation Change

[Harley Acheson]

Commit: ecc7a837982e59789b4e870b3c435e2443841172
Author: Harley Acheson
Date:   Sat May 1 09:15:03 2021 -0700
Branches: master
https://developer.blender.org/rBecc7a837982e59789b4e870b3c435e2443841172

UI: Object Thumbnails Orientation Change

Object orientation for thumbnail creation changed to be slightly
oblique (tilted to one side and from above) to better show shape,
especially when axis-aligned. Camera lens changed to 85 to avoid
distortion of close objects like human heads.

see D9940 for details and examples.

Differential Revision: https://developer.blender.org/D9940

Reviewed by Julian Eisel

===================================================================

M	source/blender/editors/render/render_preview.c

===================================================================

diff --git a/source/blender/editors/render/render_preview.c b/source/blender/editors/render/render_preview.c
index 10e0a143d9b..157f2b3ecb4 100644
--- a/source/blender/editors/render/render_preview.c
+++ b/source/blender/editors/render/render_preview.c
@@ -692,8 +692,9 @@ struct ObjectPreviewData {
   int sizey;
 };
 
-static Object *object_preview_camera_create(
-    Main *preview_main, ViewLayer *view_layer, Object *preview_object, int sizex, int sizey)
+static Object *object_preview_camera_create(Main *preview_main,
+                                            ViewLayer *view_layer,
+                                            Object *preview_object)
 {
   Object *camera = BKE_object_add(preview_main, view_layer, OB_CAMERA, "Preview Camera");
 
@@ -701,18 +702,17 @@ static Object *object_preview_camera_create(
   float dummyscale[3];
   mat4_to_loc_rot_size(camera->loc, rotmat, dummyscale, preview_object->obmat);
 
-  /* Camera is Y up, so needs additional 90deg rotation around X to match object's Z up. */
+  /* Camera is Y up, so needs additional rotations to obliquely face the front. */
   float drotmat[3][3];
-  axis_angle_to_mat3_single(drotmat, 'X', M_PI_2);
+  const float eul[3] = {M_PI * 0.4f, 0.0f, M_PI * 0.1f};
+  eul_to_mat3(drotmat, eul);
   mul_m3_m3_post(rotmat, drotmat);
 
   camera->rotmode = ROT_MODE_QUAT;
   mat3_to_quat(camera->quat, rotmat);
 
-  /* shader_preview_render() does this too. */
-  if (sizex > sizey) {
-    ((Camera *)camera->data)->lens *= (float)sizey / (float)sizex;
-  }
+  /* Nice focal length for close portraiture. */
+  ((Camera *)camera->data)->lens = 85;
 
   return camera;
 }
@@ -730,11 +730,8 @@ static Scene *object_preview_scene_create(const struct ObjectPreviewData *previe
 
   BKE_collection_object_add(preview_data->pr_main, scene->master_collection, preview_data->object);
 
-  Object *camera_object = object_preview_camera_create(preview_data->pr_main,
-                                                       view_layer,
-                                                       preview_data->object,
-                                                       preview_data->sizex,
-                                                       preview_data->sizey);
+  Object *camera_object = object_preview_camera_create(
+      preview_data->pr_main, view_layer, preview_data->object);
 
   scene->camera = camera_object;
   scene->r.xsch = preview_data->sizex;