renderdiff: add transmission and ssao tests (#9232)

- Add transmission and ssao tests
 - Small mods to README.md
 - Add transmission models to gltf list
 - Change focal length to zoom in for more details

RDIFF_BRANCH=pf/renderdiff-add-transmission

test/renderdiff/src/compare.py

@@ -229,7 +229,7 @@ if __name__ == '__main__':
   important_print(f'Successfully compared {success_count} / {len(results)} images')
 
   if tolerance_used_details:
-    pstr = 'Tolerance-based passes:'
+    pstr = 'Passed:'
     for detail in tolerance_used_details:
       pstr += '\n' + detail
     important_print(pstr)
@@ -237,7 +237,7 @@ if __name__ == '__main__':
   if failed_details:
     pstr = 'Failed:'
     for detail in failed_details:
-      pstr = '\n' + detail
+      pstr += '\n' + detail
     important_print(pstr)
   if len(failed) > 0:
     exit(1)

test/renderdiff/src/update_golden.py

@@ -74,7 +74,7 @@ def _get_deletes_updates(update_dir, golden_dir):
     for fpath in base.intersection(new):
       base_fpath = os.path.join(golden_dir, fpath)
       new_fpath = os.path.join(update_dir, fpath)
-      if (ext == 'tif' and not same_image(new_fpath, base_fpath)) or \
+      if (ext == 'tif' and not same_image(new_fpath, base_fpath)[0]) or \
          (ext == 'json' and _file_as_str(new_fpath) != _file_as_str(base_fpath)):
         update.append(fpath)