[Bf-blender-cvs] [f8bc7be60fb] temp-T101739-fix-seam-bleeding-non-manifold: Copy pixels classes.

[Jeroen Bakker]

Commit: f8bc7be60fbad611b0d3536f107056f4c382547b
Author: Jeroen Bakker
Date:   Tue Dec 20 15:23:27 2022 +0100
Branches: temp-T101739-fix-seam-bleeding-non-manifold
https://developer.blender.org/rBf8bc7be60fbad611b0d3536f107056f4c382547b

Copy pixels classes.

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

M	source/blender/blenkernel/CMakeLists.txt
A	source/blender/blenkernel/intern/pbvh_pixels_copy.cc
M	source/blender/blenlib/BLI_math_vec_types.hh

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

diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index c12c0c06ed8..c26c5d1bc4d 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -251,6 +251,7 @@ set(SRC
   intern/pbvh.cc
   intern/pbvh_bmesh.c
   intern/pbvh_pixels.cc
+  intern/pbvh_pixels_copy.cc
   intern/pbvh_uv_islands.cc
   intern/pointcache.c
   intern/pointcloud.cc
diff --git a/source/blender/blenkernel/intern/pbvh_pixels_copy.cc b/source/blender/blenkernel/intern/pbvh_pixels_copy.cc
new file mode 100644
index 00000000000..a80e6606037
--- /dev/null
+++ b/source/blender/blenkernel/intern/pbvh_pixels_copy.cc
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright 2022 Blender Foundation. All rights reserved. */
+
+#include "BLI_math_vec_types.hh"
+#include "BLI_vector.hh"
+#include "BLI_math.h"
+
+#include "IMB_imbuf.h"
+#include "IMB_imbuf_types.h"
+
+namespace blender::kernel::pbvh::pixels {
+template<typename T, int Channels = 4> struct ImageBufferAccessor {
+  ImBuf &image_buffer;
+
+  ImageBufferAccessor(ImBuf &image_buffer) : image_buffer(image_buffer)
+  {
+  }
+
+  float4 read_pixel(const int2 coordinate)
+  {
+    int offset = (coordinate.y * image_buffer.x + coordinate.x) * Channels;
+    return float4(&image_buffer.rect_float[offset]);
+  }
+
+  void write_pixel(const int2 coordinate, float4 new_value)
+  {
+    int offset = (coordinate.y * image_buffer.x + coordinate.x) * Channels;
+    copy_v4_v4(&image_buffer.rect_float[offset], new_value);
+  }
+};
+
+struct PixelCopyItem {
+  uint8_t delta_destination_x;
+  char2 delta_source_1;
+  char2 delta_source_2;
+  uint8_t mix_factor;
+};
+
+struct PixelCopyGroup {
+  int2 destination;
+  Vector<PixelCopyItem> items;
+};
+
+/** Pixel copy command to mix 2 source pixels and write to a destination pixel. */
+struct PixelCopyCommand {
+  /** Pixel coordinate to write to. */
+  int2 destination;
+  /** Pixel coordinate to read first source from. */
+  int2 source_1;
+  /** Pixel coordinate to read second source from. */
+  int2 source_2;
+  /** Factor to mix between first and second source. */
+  float mix_factor;
+
+  PixelCopyCommand(const PixelCopyGroup &group)
+      : destination(group.destination),
+        source_1(group.destination),
+        source_2(group.destination),
+        mix_factor(0.0f)
+  {
+  }
+
+  template<typename T> void mix_source_and_write_destination(ImageBufferAccessor<T> &tile_buffer) const
+  {
+    float4 source_color_1 = tile_buffer.read_pixel(source_1);
+    float4 source_color_2 = tile_buffer.read_pixel(source_2);
+    float4 destination_color = source_color_1 * (1.0f - mix_factor) + source_color_2 * mix_factor;
+    tile_buffer.write_pixel(destination, destination_color);
+  }
+};
+
+PixelCopyCommand &operator+=(PixelCopyCommand &command, const PixelCopyItem &item)
+{
+  command.destination.x += int(item.delta_destination_x);
+  command.source_1 += int2(item.delta_source_1);
+  command.source_2 += int2(item.delta_source_2);
+  command.mix_factor = float(item.mix_factor) / 255.0f;
+  return command;
+}
+
+struct PixelCopyGroups {
+  Vector<PixelCopyGroup> groups;
+
+  void copy_pixels(ImBuf &tile_buffer) const
+  {
+    if (tile_buffer.rect_float) {
+      ImageBufferAccessor<float4> accessor(tile_buffer);
+      copy_pixels<float4>(accessor);
+    }
+    else {
+      ImageBufferAccessor<int> accessor(tile_buffer);
+      copy_pixels<int>(accessor);
+    }
+  }
+
+ private:
+  template<typename T> void copy_pixels(ImageBufferAccessor<T> &image_buffer) const
+  {
+    for (const PixelCopyGroup &group : groups) {
+      PixelCopyCommand copy_command(group);
+      for (const PixelCopyItem &item : group.items) {
+        copy_command += item;
+        copy_command.mix_source_and_write_destination<T>(image_buffer);
+      }
+    }
+  }
+};
+
+}  // namespace blender::kernel::pbvh::pixels
diff --git a/source/blender/blenlib/BLI_math_vec_types.hh b/source/blender/blenlib/BLI_math_vec_types.hh
index f57b4b44e61..20a8539c67c 100644
--- a/source/blender/blenlib/BLI_math_vec_types.hh
+++ b/source/blender/blenlib/BLI_math_vec_types.hh
@@ -602,6 +602,7 @@ template<typename T, int Size> struct vec_base : public vec_struct_base<T, Size>
   }
 };
 
+using char2 = blender::vec_base<int8_t, 2>;
 using char3 = blender::vec_base<int8_t, 3>;
 
 using uchar3 = blender::vec_base<uint8_t, 3>;