Fix Cycles packed images not handling channel packed alpha correctly

1 files changed, 12 insertions, 8 deletions

diff --git a/intern/cycles/blender/blender_session.cpp b/intern/cycles/blender/blender_session.cpp
index 11b6a38c195..bb7c750078f 100644
--- a/intern/cycles/blender/blender_session.cpp
+++ b/intern/cycles/blender/blender_session.cpp
@@ -147,9 +147,9 @@ void BlenderSession::create_session()
   scene->image_manager->builtin_image_info_cb = function_bind(
       &BlenderSession::builtin_image_info, this, _1, _2, _3);
   scene->image_manager->builtin_image_pixels_cb = function_bind(
-      &BlenderSession::builtin_image_pixels, this, _1, _2, _3, _4, _5);
+      &BlenderSession::builtin_image_pixels, this, _1, _2, _3, _4, _5, _6);
   scene->image_manager->builtin_image_float_pixels_cb = function_bind(
-      &BlenderSession::builtin_image_float_pixels, this, _1, _2, _3, _4, _5);
+      &BlenderSession::builtin_image_float_pixels, this, _1, _2, _3, _4, _5, _6);
 
   session->scene = scene;
 
@@ -1223,6 +1223,7 @@ bool BlenderSession::builtin_image_pixels(const string &builtin_name,
                                           void *builtin_data,
                                           unsigned char *pixels,
                                           const size_t pixels_size,
+                                          const bool associate_alpha,
                                           const bool free_cache)
 {
   if (!builtin_data) {
@@ -1272,12 +1273,14 @@ bool BlenderSession::builtin_image_pixels(const string &builtin_name,
     b_image.buffers_free();
   }
 
-  /* Premultiply, byte images are always straight for Blender. */
-  unsigned char *cp = pixels;
-  for (size_t i = 0; i < num_pixels; i++, cp += channels) {
-    cp[0] = (cp[0] * cp[3]) >> 8;
-    cp[1] = (cp[1] * cp[3]) >> 8;
-    cp[2] = (cp[2] * cp[3]) >> 8;
+  if (associate_alpha) {
+    /* Premultiply, byte images are always straight for Blender. */
+    unsigned char *cp = pixels;
+    for (size_t i = 0; i < num_pixels; i++, cp += channels) {
+      cp[0] = (cp[0] * cp[3]) >> 8;
+      cp[1] = (cp[1] * cp[3]) >> 8;
+      cp[2] = (cp[2] * cp[3]) >> 8;
+    }
   }
   return true;
 }
@@ -1286,6 +1289,7 @@ bool BlenderSession::builtin_image_float_pixels(const string &builtin_name,
                                                 void *builtin_data,
                                                 float *pixels,
                                                 const size_t pixels_size,
+                                                const bool,
                                                 const bool free_cache)
 {
   if (!builtin_data) {