Cleanup: DRW manager: Move `select_buffer.c` utilities out of the selection engine internals

4 files changed, 4 insertions, 534 deletions

diff --git a/source/blender/draw/engines/select/select_buffer.c b/source/blender/draw/engines/select/select_buffer.c
deleted file mode 100644
index b184992cb56..00000000000
--- a/source/blender/draw/engines/select/select_buffer.c
+++ /dev/null
@@ -1,500 +0,0 @@
-/*
- * 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.
- *
- * Copyright 2019, Blender Foundation.
- */
-
-/** \file
- * \ingroup draw_engine
- *
- * Utilities to read id buffer created in select_engine.
- */
-
-#include "MEM_guardedalloc.h"
-
-#include "BLI_bitmap.h"
-#include "BLI_bitmap_draw_2d.h"
-#include "BLI_rect.h"
-
-#include "DNA_screen_types.h"
-
-#include "GPU_select.h"
-
-#include "DRW_engine.h"
-#include "DRW_select_buffer.h"
-
-#include "select_private.h"
-#include "select_engine.h"
-
-/* -------------------------------------------------------------------- */
-/** \name Buffer of select ID's
- * \{ */
-
-/* Read a block of pixels from the select frame buffer. */
-uint *DRW_select_buffer_read(const rcti *rect, uint *r_buf_len)
-{
-  struct SELECTID_Context *select_ctx = select_context_get();
-
-  /* clamp rect by texture */
-  rcti r = {
-      .xmin = 0,
-      .xmax = GPU_texture_width(select_ctx->texture_u32),
-      .ymin = 0,
-      .ymax = GPU_texture_height(select_ctx->texture_u32),
-  };
-
-  rcti rect_clamp = *rect;
-  if (BLI_rcti_isect(&r, &rect_clamp, &rect_clamp)) {
-    uint buf_len = BLI_rcti_size_x(rect) * BLI_rcti_size_y(rect);
-    uint *r_buf = MEM_mallocN(buf_len * sizeof(*r_buf), __func__);
-
-    DRW_opengl_context_enable();
-    GPU_framebuffer_bind(select_ctx->framebuffer_select_id);
-    glReadBuffer(GL_COLOR_ATTACHMENT0);
-    glReadPixels(rect_clamp.xmin,
-                 rect_clamp.ymin,
-                 BLI_rcti_size_x(&rect_clamp),
-                 BLI_rcti_size_y(&rect_clamp),
-                 GL_RED_INTEGER,
-                 GL_UNSIGNED_INT,
-                 r_buf);
-
-    GPU_framebuffer_restore();
-    DRW_opengl_context_disable();
-
-    if (!BLI_rcti_compare(rect, &rect_clamp)) {
-      GPU_select_buffer_stride_realign(rect, &rect_clamp, r_buf);
-    }
-
-    if (r_buf_len) {
-      *r_buf_len = buf_len;
-    }
-
-    return r_buf;
-  }
-  return NULL;
-}
-
-/** \} */
-
-/* -------------------------------------------------------------------- */
-/** \name Select Bitmap from ID's
- *
- * Given a buffer of select ID's, fill in a booleans (true/false) per index.
- * #BLI_bitmap is used for memory efficiency.
- *
- * \{ */
-
-/**
- * \param rect: The rectangle to sample indices from (min/max inclusive).
- * \param mask: Specifies the rect pixels (optional).
- * \returns a #BLI_bitmap the length of \a bitmap_len or NULL on failure.
- */
-uint *DRW_select_buffer_bitmap_from_rect(const rcti *rect, uint *r_bitmap_len)
-{
-  struct SELECTID_Context *select_ctx = select_context_get();
-
-  const uint bitmap_len = select_ctx->last_index_drawn;
-  if (bitmap_len == 0) {
-    return NULL;
-  }
-
-  rcti rect_px = *rect;
-  rect_px.xmax += 1;
-  rect_px.ymax += 1;
-
-  uint buf_len;
-  uint *buf = DRW_select_buffer_read(&rect_px, &buf_len);
-  if (buf == NULL) {
-    return NULL;
-  }
-
-  BLI_bitmap *bitmap_buf = BLI_BITMAP_NEW(bitmap_len, __func__);
-  const uint *buf_iter = buf;
-  while (buf_len--) {
-    const uint index = *buf_iter - 1;
-    if (index < bitmap_len) {
-      BLI_BITMAP_ENABLE(bitmap_buf, index);
-    }
-    buf_iter++;
-  }
-  MEM_freeN((void *)buf);
-
-  if (r_bitmap_len) {
-    *r_bitmap_len = bitmap_len;
-  }
-
-  return bitmap_buf;
-}
-
-/**
- * \param bitmap_len: Number of indices in the selection id buffer.
- * \param center: Circle center.
- * \param radius: Circle radius.
- * \returns a #BLI_bitmap the length of \a bitmap_len or NULL on failure.
- */
-uint *DRW_select_buffer_bitmap_from_circle(const int center[2],
-                                           const int radius,
-                                           uint *r_bitmap_len)
-{
-  struct SELECTID_Context *select_ctx = select_context_get();
-
-  const uint bitmap_len = select_ctx->last_index_drawn;
-  if (bitmap_len == 0) {
-    return NULL;
-  }
-
-  const rcti rect = {
-      .xmin = center[0] - radius,
-      .xmax = center[0] + radius + 1,
-      .ymin = center[1] - radius,
-      .ymax = center[1] + radius + 1,
-  };
-
-  const uint *buf = DRW_select_buffer_read(&rect, NULL);
-
-  if (buf == NULL) {
-    return NULL;
-  }
-
-  const uint *buf_iter = buf;
-
-  BLI_bitmap *bitmap_buf = BLI_BITMAP_NEW(bitmap_len, __func__);
-  const int radius_sq = radius * radius;
-  for (int yc = -radius; yc <= radius; yc++) {
-    for (int xc = -radius; xc <= radius; xc++, buf_iter++) {
-      if (xc * xc + yc * yc < radius_sq) {
-        /* Intentionally wrap to max value if this is zero. */
-        const uint index = *buf_iter - 1;
-        if (index < bitmap_len) {
-          BLI_BITMAP_ENABLE(bitmap_buf, index);
-        }
-      }
-    }
-  }
-  MEM_freeN((void *)buf);
-
-  if (r_bitmap_len) {
-    *r_bitmap_len = bitmap_len;
-  }
-
-  return bitmap_buf;
-}
-
-struct PolyMaskData {
-  BLI_bitmap *px;
-  int width;
-};
-
-static void drw_select_mask_px_cb(int x, int x_end, int y, void *user_data)
-{
-  struct PolyMaskData *data = user_data;
-  BLI_bitmap *px = data->px;
-  int i = (y * data->width) + x;
-  do {
-    BLI_BITMAP_ENABLE(px, i);
-    i++;
-  } while (++x != x_end);
-}
-
-/**
- * \param poly: The polygon coordinates.
- * \param poly_len: Length of the polygon.
- * \param rect: Polygon boundaries.
- * \returns a #BLI_bitmap.
- */
-uint *DRW_select_buffer_bitmap_from_poly(const int poly[][2], const int poly_len, const rcti *rect)
-{
-  struct SELECTID_Context *select_ctx = select_context_get();
-
-  const uint bitmap_len = select_ctx->last_index_drawn;
-  if (bitmap_len == 0) {
-    return NULL;
-  }
-
-  rcti rect_px = *rect;
-  rect_px.xmax += 1;
-  rect_px.ymax += 1;
-
-  uint buf_len;
-  uint *buf = DRW_select_buffer_read(&rect_px, &buf_len);
-  if (buf == NULL) {
-    return NULL;
-  }
-
-  BLI_bitmap *buf_mask = BLI_BITMAP_NEW(buf_len, __func__);
-
-  struct PolyMaskData poly_mask_data;
-  poly_mask_data.px = buf_mask;
-  poly_mask_data.width = (rect->xmax - rect->xmin) + 1;
-
-  BLI_bitmap_draw_2d_poly_v2i_n(rect_px.xmin,
-                                rect_px.ymin,
-                                rect_px.xmax,
-                                rect_px.ymax,
-                                poly,
-                                poly_len,
-                                drw_select_mask_px_cb,
-                                &poly_mask_data);
-
-  BLI_bitmap *bitmap_buf = BLI_BITMAP_NEW(bitmap_len, __func__);
-  const uint *buf_iter = buf;
-  int i = 0;
-  while (buf_len--) {
-    const uint index = *buf_iter - 1;
-    if (index < bitmap_len && BLI_BITMAP_TEST(buf_mask, i)) {
-      BLI_BITMAP_ENABLE(bitmap_buf, index);
-    }
-    buf_iter++;
-    i++;
-  }
-  MEM_freeN((void *)buf);
-  MEM_freeN(buf_mask);
-
-  return bitmap_buf;
-}
-
-/** \} */
-
-/* -------------------------------------------------------------------- */
-/** \name Find Single Select ID's
- *
- * Given a buffer of select ID's, find the a single select id.
- *
- * \{ */
-
-/**
- * Samples a single pixel.
- */
-uint DRW_select_buffer_sample_point(const int center[2])
-{
-  const rcti rect = {
-      .xmin = center[0],
-      .xmax = center[0] + 1,
-      .ymin = center[1],
-      .ymax = center[1] + 1,
-  };
-
-  uint buf_len;
-  uint *buf = DRW_select_buffer_read(&rect, &buf_len);
-  BLI_assert(0 != buf_len);
-  uint ret = buf[0];
-  MEM_freeN(buf);
-  return ret;
-}
-
-/**
- * Find the selection id closest to \a center.
- * \param dist[in,out]: Use to initialize the distance,
- * when found, this value is set to the distance of the selection that's returned.
- */
-uint DRW_select_buffer_find_nearest_to_point(const int center[2],
-                                             const uint id_min,
-                                             const uint id_max,
-                                             uint *dist)
-{
-  /* Smart function to sample a rect spiraling outside, nice for selection ID. */
-
-  /* Create region around center (typically the mouse cursor).
-   * This must be square and have an odd width,
-   * the spiraling algorithm does not work with arbitrary rectangles. */
-
-  uint index = 0;
-
-  rcti rect;
-  BLI_rcti_init_pt_radius(&rect, center, *dist);
-  rect.xmax += 1;
-  rect.ymax += 1;
-
-  int width = BLI_rcti_size_x(&rect);
-  int height = width;
-  BLI_assert(width == height);
-
-  /* Read from selection framebuffer. */
-
-  uint buf_len;
-  const uint *buf = DRW_select_buffer_read(&rect, &buf_len);
-
-  if (buf == NULL) {
-    return index;
-  }
-
-  BLI_assert(width * height == buf_len);
-
-  /* Spiral, starting from center of buffer. */
-  int spiral_offset = height * (int)(width / 2) + (height / 2);
-  int spiral_direction = 0;
-
-  for (int nr = 1; nr <= height; nr++) {
-    for (int a = 0; a < 2; a++) {
-      for (int b = 0; b < nr; b++) {
-        /* Find hit within the specified range. */
-        uint hit_id = buf[spiral_offset];
-
-        if (hit_id && hit_id >= id_min && hit_id < id_max) {
-          /* Get x/y from spiral offset. */
-          int hit_x = spiral_offset % width;
-          int hit_y = spiral_offset / width;
-
-          int center_x = width / 2;
-          int center_y = height / 2;
-
-          /* Manhatten distance in keeping with other screen-based selection. */
-          *dist = (uint)(abs(hit_x - center_x) + abs(hit_y - center_y));
-
-          /* Indices start at 1 here. */
-          index = (hit_id - id_min) + 1;
-          goto exit;
-        }
-
-        /* Next spiral step. */
-        if (spiral_direction == 0) {
-          spiral_offset += 1; /* right */
-        }
-        else if (spiral_direction == 1) {
-          spiral_offset -= width; /* down */
-        }
-        else if (spiral_direction == 2) {
-          spiral_offset -= 1; /* left */
-        }
-        else {
-          spiral_offset += width; /* up */
-        }
-
-        /* Stop if we are outside the buffer. */
-        if (spiral_offset < 0 || spiral_offset >= buf_len) {
-          goto exit;
-        }
-      }
-
-      spiral_direction = (spiral_direction + 1) % 4;
-    }
-  }
-
-exit:
-  MEM_freeN((void *)buf);
-  return index;
-}
-
-/** \} */
-
-/* -------------------------------------------------------------------- */
-/** \name Object Utils
- * \{ */
-
-bool DRW_select_buffer_elem_get(const uint sel_id,
-                                uint *r_elem,
-                                uint *r_base_index,
-                                char *r_elem_type)
-{
-  struct SELECTID_Context *select_ctx = select_context_get();
-
-  char elem_type = 0;
-  uint elem_id;
-  uint base_index = 0;
-
-  for (; base_index < select_ctx->objects_len; base_index++) {
-    struct BaseOffset *base_ofs = &select_ctx->index_offsets[base_index];
-
-    if (base_ofs->face > sel_id) {
-      elem_id = sel_id - base_ofs->face_start;
-      elem_type = SCE_SELECT_FACE;
-      break;
-    }
-    if (base_ofs->edge > sel_id) {
-      elem_id = sel_id - base_ofs->edge_start;
-      elem_type = SCE_SELECT_EDGE;
-      break;
-    }
-    if (base_ofs->vert > sel_id) {
-      elem_id = sel_id - base_ofs->vert_start;
-      elem_type = SCE_SELECT_VERTEX;
-      break;
-    }
-  }
-
-  if (base_index == select_ctx->objects_len) {
-    return false;
-  }
-
-  *r_elem = elem_id;
-
-  if (r_base_index) {
-    *r_base_index = base_index;
-  }
-
-  if (r_elem_type) {
-    *r_elem_type = elem_type;
-  }
-
-  return true;
-}
-
-uint DRW_select_buffer_context_offset_for_object_elem(const uint base_index, char elem_type)
-{
-  struct SELECTID_Context *select_ctx = select_context_get();
-  struct BaseOffset *base_ofs = &select_ctx->index_offsets[base_index];
-
-  if (elem_type == SCE_SELECT_VERTEX) {
-    return base_ofs->vert_start - 1;
-  }
-  if (elem_type == SCE_SELECT_EDGE) {
-    return base_ofs->edge_start - 1;
-  }
-  if (elem_type == SCE_SELECT_FACE) {
-    return base_ofs->face_start - 1;
-  }
-  BLI_assert(0);
-  return 0;
-}
-
-/** \} */
-
-/* -------------------------------------------------------------------- */
-/** \name Context
- * \{ */
-
-void DRW_select_buffer_context_create(Base **UNUSED(bases),
-                                      const uint bases_len,
-                                      short select_mode)
-{
-  struct SELECTID_Context *select_ctx = select_context_get();
-
-  select_ctx->select_mode = select_mode;
-  select_ctx->objects_len = bases_len;
-
-  MEM_SAFE_FREE(select_ctx->index_offsets);
-  select_ctx->index_offsets = MEM_mallocN(sizeof(*select_ctx->index_offsets) * bases_len,
-                                          __func__);
-}
-
-/** \} */
-
-/* -------------------------------------------------------------------- */
-/** \name Legacy
- * \{ */
-
-void DRW_draw_select_id_object(Depsgraph *depsgraph,
-                               ViewLayer *view_layer,
-                               ARegion *ar,
-                               View3D *v3d,
-                               Object *ob,
-                               short select_mode)
-{
-  Base *base = BKE_view_layer_base_find(view_layer, ob);
-  DRW_draw_select_id(depsgraph, ar, v3d, &base, 1, select_mode);
-}
-
-/** \} */
diff --git a/source/blender/draw/engines/select/select_draw_utils.c b/source/blender/draw/engines/select/select_draw_utils.c
index c3ee7f962a1..b65a158cdcf 100644
--- a/source/blender/draw/engines/select/select_draw_utils.c
+++ b/source/blender/draw/engines/select/select_draw_utils.c
@@ -32,6 +32,8 @@
 #include "DEG_depsgraph.h"
 #include "DEG_depsgraph_query.h"
 
+#include "DRW_select_buffer.h"
+
 #include "draw_cache_impl.h"
 
 #include "select_private.h"
diff --git a/source/blender/draw/engines/select/select_engine.c b/source/blender/draw/engines/select/select_engine.c
index 3e4e4861f50..83f6563ab53 100644
--- a/source/blender/draw/engines/select/select_engine.c
+++ b/source/blender/draw/engines/select/select_engine.c
@@ -29,6 +29,7 @@
 #include "UI_resources.h"
 
 #include "DRW_engine.h"
+#include "DRW_select_buffer.h"
 
 #include "select_private.h"
 #include "select_engine.h"
@@ -272,7 +273,7 @@ RenderEngineType DRW_engine_viewport_select_type = {
 /** \name Exposed `select_private.h` functions
  * \{ */
 
-struct SELECTID_Context *select_context_get(void)
+struct SELECTID_Context *DRW_select_engine_context_get(void)
 {
   return &e_data.context;
 }
diff --git a/source/blender/draw/engines/select/select_private.h b/source/blender/draw/engines/select/select_private.h
index 2104f1485e7..d95b14ff2b6 100644
--- a/source/blender/draw/engines/select/select_private.h
+++ b/source/blender/draw/engines/select/select_private.h
@@ -62,39 +62,6 @@ typedef struct SELECTID_PrivateData {
   DRWView *view_verts;
 } SELECTID_PrivateData; /* Transient data */
 
-struct BaseOffset {
-  /* For convenience only. */
-  union {
-    uint offset;
-    uint face_start;
-  };
-  union {
-    uint face;
-    uint edge_start;
-  };
-  union {
-    uint edge;
-    uint vert_start;
-  };
-  uint vert;
-};
-
-struct SELECTID_Context {
-  struct GPUFrameBuffer *framebuffer_select_id;
-  struct GPUTexture *texture_u32;
-
-  struct BaseOffset *index_offsets;
-  uint objects_len;
-  uint last_object_drawn;
-  /** Total number of items `base_array_index_offsets[bases_len - 1].vert`. */
-  uint last_index_drawn;
-
-  short select_mode;
-};
-
-/* select_engine.c */
-struct SELECTID_Context *select_context_get(void);
-
 /* select_draw_utils.c */
 void draw_select_framebuffer_select_id_setup(struct SELECTID_Context *r_select_ctx);
 short select_id_get_object_select_mode(Scene *scene, Object *ob);