Image: Partial Update Redesign.

This patch reimplements the image partial updates. Biggest design motivation for the redesign
is that currently GPUTextures must be owned by the image. This reduces flexibility and adds
complexity to a single component especially when we want to have different structures.

The new design is not limited to GPUTextures and can also be used by reducing overhead in image
operations like scaling. Or partial image updating in Cycles.

The usecase in hand is that we want to support virtual images in the image editor so we can
work with images that don't fit in a single GPUTexture.

Using `BKE_image_partial_update_mark_region` or `BKE_image_partial_update_mark_full_update`
a part of an image can be marked as dirty. These regions are stored per ImageTile (UDIM).

When a part of the code wants to receive partial changes it needs to construct a `PartialUpdateUser`
by calling `BKE_image_partial_update_create`. As long as this instance is kept alive the changes can
be received.

When a user wants to update its own data it will call `BKE_image_partial_update_collect_changes`
This will collect the changes since the last time the user called this function. When the partial changes
are available the partial change can be read by calling `BKE_image_partial_update_get_next_change`

It can happen that the introduced mechanism doesn't have the data anymore to construct the
changes since the last time a PartialUpdateUser requested it. In this case it will get a request
to perform a full update.

Maniphest Tasks: T92613

Differential Revision: https://developer.blender.org/D13238

1 files changed, 393 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/image_partial_update_test.cc b/source/blender/blenkernel/intern/image_partial_update_test.cc
new file mode 100644
index 00000000000..70aa51f7c98
--- /dev/null
+++ b/source/blender/blenkernel/intern/image_partial_update_test.cc
@@ -0,0 +1,393 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2020 by Blender Foundation.
+ */
+#include "testing/testing.h"
+
+#include "CLG_log.h"
+
+#include "BKE_appdir.h"
+#include "BKE_idtype.h"
+#include "BKE_image.h"
+#include "BKE_image_partial_update.hh"
+#include "BKE_main.h"
+
+#include "IMB_imbuf.h"
+#include "IMB_moviecache.h"
+
+#include "DNA_image_types.h"
+
+#include "MEM_guardedalloc.h"
+
+namespace blender::bke::image::partial_update {
+
+constexpr float black_color[4] = {0.0f, 0.0f, 0.0f, 1.0f};
+
+class ImagePartialUpdateTest : public testing::Test {
+ protected:
+  Main *bmain;
+  Image *image;
+  ImageTile *image_tile;
+  ImageUser image_user = {nullptr};
+  ImBuf *image_buffer;
+  PartialUpdateUser *partial_update_user;
+
+ private:
+  Image *create_test_image(int width, int height)
+  {
+    return BKE_image_add_generated(bmain,
+                                   width,
+                                   height,
+                                   "Test Image",
+                                   32,
+                                   true,
+                                   IMA_GENTYPE_BLANK,
+                                   black_color,
+                                   false,
+                                   false,
+                                   false);
+  }
+
+ protected:
+  void SetUp() override
+  {
+    CLG_init();
+    BKE_idtype_init();
+    BKE_appdir_init();
+    IMB_init();
+
+    bmain = BKE_main_new();
+    /* Creating an image generates a mem-leak during tests. */
+    image = create_test_image(1024, 1024);
+    image_tile = BKE_image_get_tile(image, 0);
+    image_buffer = BKE_image_acquire_ibuf(image, nullptr, nullptr);
+
+    partial_update_user = BKE_image_partial_update_create(image);
+  }
+
+  void TearDown() override
+  {
+    BKE_image_release_ibuf(image, image_buffer, nullptr);
+    BKE_image_partial_update_free(partial_update_user);
+    BKE_main_free(bmain);
+
+    IMB_moviecache_destruct();
+    IMB_exit();
+    BKE_appdir_exit();
+    CLG_exit();
+  }
+};
+
+TEST_F(ImagePartialUpdateTest, mark_full_update)
+{
+  ePartialUpdateCollectResult result;
+  /* First tile should always return a full update. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::FullUpdateNeeded);
+  /* Second invoke should now detect no changes. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  /* Mark full update */
+  BKE_image_partial_update_mark_full_update(image);
+
+  /* Validate need full update followed by no changes. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::FullUpdateNeeded);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+}
+
+TEST_F(ImagePartialUpdateTest, mark_single_tile)
+{
+  ePartialUpdateCollectResult result;
+  /* First tile should always return a full update. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::FullUpdateNeeded);
+  /* Second invoke should now detect no changes. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  /* Mark region. */
+  rcti region;
+  BLI_rcti_init(&region, 10, 20, 40, 50);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+
+  /* Partial Update should be available. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::PartialChangesDetected);
+
+  /* Check tiles. */
+  PartialUpdateRegion changed_region;
+  ePartialUpdateIterResult iter_result;
+  iter_result = BKE_image_partial_update_get_next_change(partial_update_user, &changed_region);
+  EXPECT_EQ(iter_result, ePartialUpdateIterResult::ChangeAvailable);
+  EXPECT_EQ(BLI_rcti_inside_rcti(&changed_region.region, &region), true);
+  iter_result = BKE_image_partial_update_get_next_change(partial_update_user, &changed_region);
+  EXPECT_EQ(iter_result, ePartialUpdateIterResult::Finished);
+
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+}
+
+TEST_F(ImagePartialUpdateTest, mark_unconnected_tiles)
+{
+  ePartialUpdateCollectResult result;
+  /* First tile should always return a full update. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::FullUpdateNeeded);
+  /* Second invoke should now detect no changes. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  /* Mark region. */
+  rcti region_a;
+  BLI_rcti_init(&region_a, 10, 20, 40, 50);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region_a);
+  rcti region_b;
+  BLI_rcti_init(&region_b, 710, 720, 740, 750);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region_b);
+
+  /* Partial Update should be available. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::PartialChangesDetected);
+
+  /* Check tiles. */
+  PartialUpdateRegion changed_region;
+  ePartialUpdateIterResult iter_result;
+  iter_result = BKE_image_partial_update_get_next_change(partial_update_user, &changed_region);
+  EXPECT_EQ(iter_result, ePartialUpdateIterResult::ChangeAvailable);
+  EXPECT_EQ(BLI_rcti_inside_rcti(&changed_region.region, &region_b), true);
+  iter_result = BKE_image_partial_update_get_next_change(partial_update_user, &changed_region);
+  EXPECT_EQ(iter_result, ePartialUpdateIterResult::ChangeAvailable);
+  EXPECT_EQ(BLI_rcti_inside_rcti(&changed_region.region, &region_a), true);
+  iter_result = BKE_image_partial_update_get_next_change(partial_update_user, &changed_region);
+  EXPECT_EQ(iter_result, ePartialUpdateIterResult::Finished);
+
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+}
+
+TEST_F(ImagePartialUpdateTest, donot_mark_outside_image)
+{
+  ePartialUpdateCollectResult result;
+  /* First tile should always return a full update. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::FullUpdateNeeded);
+  /* Second invoke should now detect no changes. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  /* Mark region. */
+  rcti region;
+  /* Axis. */
+  BLI_rcti_init(&region, -100, 0, 50, 100);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  BLI_rcti_init(&region, 1024, 1100, 50, 100);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  BLI_rcti_init(&region, 50, 100, -100, 0);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  BLI_rcti_init(&region, 50, 100, 1024, 1100);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  /* Diagonals. */
+  BLI_rcti_init(&region, -100, 0, -100, 0);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  BLI_rcti_init(&region, -100, 0, 1024, 1100);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  BLI_rcti_init(&region, 1024, 1100, -100, 0);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  BLI_rcti_init(&region, 1024, 1100, 1024, 1100);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+}
+
+TEST_F(ImagePartialUpdateTest, mark_inside_image)
+{
+  ePartialUpdateCollectResult result;
+  /* First tile should always return a full update. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::FullUpdateNeeded);
+  /* Second invoke should now detect no changes. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  /* Mark region. */
+  rcti region;
+  BLI_rcti_init(&region, 0, 1, 0, 1);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::PartialChangesDetected);
+
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+  BLI_rcti_init(&region, 1023, 1024, 0, 1);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::PartialChangesDetected);
+
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+  BLI_rcti_init(&region, 1023, 1024, 1023, 1024);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::PartialChangesDetected);
+
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+  BLI_rcti_init(&region, 1023, 1024, 0, 1);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::PartialChangesDetected);
+}
+
+TEST_F(ImagePartialUpdateTest, sequential_mark_region)
+{
+  ePartialUpdateCollectResult result;
+  /* First tile should always return a full update. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::FullUpdateNeeded);
+  /* Second invoke should now detect no changes. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  {
+    /* Mark region. */
+    rcti region;
+    BLI_rcti_init(&region, 10, 20, 40, 50);
+    BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+
+    /* Partial Update should be available. */
+    result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+    EXPECT_EQ(result, ePartialUpdateCollectResult::PartialChangesDetected);
+
+    /* Check tiles. */
+    PartialUpdateRegion changed_region;
+    ePartialUpdateIterResult iter_result;
+    iter_result = BKE_image_partial_update_get_next_change(partial_update_user, &changed_region);
+    EXPECT_EQ(iter_result, ePartialUpdateIterResult::ChangeAvailable);
+    EXPECT_EQ(BLI_rcti_inside_rcti(&changed_region.region, &region), true);
+    iter_result = BKE_image_partial_update_get_next_change(partial_update_user, &changed_region);
+    EXPECT_EQ(iter_result, ePartialUpdateIterResult::Finished);
+
+    result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+    EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+  }
+
+  {
+    /* Mark different region. */
+    rcti region;
+    BLI_rcti_init(&region, 710, 720, 740, 750);
+    BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+
+    /* Partial Update should be available. */
+    result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+    EXPECT_EQ(result, ePartialUpdateCollectResult::PartialChangesDetected);
+
+    /* Check tiles. */
+    PartialUpdateRegion changed_region;
+    ePartialUpdateIterResult iter_result;
+    iter_result = BKE_image_partial_update_get_next_change(partial_update_user, &changed_region);
+    EXPECT_EQ(iter_result, ePartialUpdateIterResult::ChangeAvailable);
+    EXPECT_EQ(BLI_rcti_inside_rcti(&changed_region.region, &region), true);
+    iter_result = BKE_image_partial_update_get_next_change(partial_update_user, &changed_region);
+    EXPECT_EQ(iter_result, ePartialUpdateIterResult::Finished);
+
+    result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+    EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+  }
+}
+
+TEST_F(ImagePartialUpdateTest, mark_multiple_chunks)
+{
+  ePartialUpdateCollectResult result;
+  /* First tile should always return a full update. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::FullUpdateNeeded);
+  /* Second invoke should now detect no changes. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::NoChangesDetected);
+
+  /* Mark region. */
+  rcti region;
+  BLI_rcti_init(&region, 300, 700, 300, 700);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+
+  /* Partial Update should be available. */
+  result = BKE_image_partial_update_collect_changes(image, partial_update_user);
+  EXPECT_EQ(result, ePartialUpdateCollectResult::PartialChangesDetected);
+
+  /* Check tiles. */
+  PartialUpdateRegion changed_region;
+  int num_chunks_found = 0;
+  while (BKE_image_partial_update_get_next_change(partial_update_user, &changed_region) ==
+         ePartialUpdateIterResult::ChangeAvailable) {
+    BLI_rcti_isect(&changed_region.region, &region, nullptr);
+    num_chunks_found++;
+  }
+  EXPECT_EQ(num_chunks_found, 4);
+}
+
+TEST_F(ImagePartialUpdateTest, iterator)
+{
+  PartialUpdateChecker<NoTileData> checker(image, &image_user, partial_update_user);
+  /* First tile should always return a full update. */
+  PartialUpdateChecker<NoTileData>::CollectResult changes = checker.collect_changes();
+  EXPECT_EQ(changes.get_result_code(), ePartialUpdateCollectResult::FullUpdateNeeded);
+  /* Second invoke should now detect no changes. */
+  changes = checker.collect_changes();
+  EXPECT_EQ(changes.get_result_code(), ePartialUpdateCollectResult::NoChangesDetected);
+
+  /* Mark region. */
+  rcti region;
+  BLI_rcti_init(&region, 300, 700, 300, 700);
+  BKE_image_partial_update_mark_region(image, image_tile, image_buffer, &region);
+
+  /* Partial Update should be available. */
+  changes = checker.collect_changes();
+  EXPECT_EQ(changes.get_result_code(), ePartialUpdateCollectResult::PartialChangesDetected);
+
+  /* Check tiles. */
+  int num_tiles_found = 0;
+  while (changes.get_next_change() == ePartialUpdateIterResult::ChangeAvailable) {
+    BLI_rcti_isect(&changes.changed_region.region, &region, nullptr);
+    num_tiles_found++;
+  }
+  EXPECT_EQ(num_tiles_found, 4);
+}
+
+}  // namespace blender::bke::image::partial_update