Painting: migrated curve mask generation to CPP.

Curve mask generation is done during 2d texture painting. There are some
performance issues in this part of the code. Before addressing those we
move the code to CPP.

1 files changed, 6 insertions, 97 deletions

diff --git a/source/blender/editors/sculpt_paint/paint_image_2d.c b/source/blender/editors/sculpt_paint/paint_image_2d.c
index 318180e5eb4..7191431cf4c 100644
--- a/source/blender/editors/sculpt_paint/paint_image_2d.c
+++ b/source/blender/editors/sculpt_paint/paint_image_2d.c
@@ -78,12 +78,13 @@ typedef struct BrushPainterCache {
 
   ImBuf *ibuf;
   ImBuf *texibuf;
-  ushort *curve_mask;
   ushort *tex_mask;
   ushort *tex_mask_old;
   uint tex_mask_old_w;
   uint tex_mask_old_h;
 
+  CurveMaskCache curve_mask_cache;
+
   int image_size[2];
 } BrushPainterCache;
 
@@ -169,9 +170,6 @@ static void brush_painter_2d_require_imbuf(
     if (cache->ibuf) {
       IMB_freeImBuf(cache->ibuf);
     }
-    if (cache->curve_mask) {
-      MEM_freeN(cache->curve_mask);
-    }
     if (cache->tex_mask) {
       MEM_freeN(cache->tex_mask);
     }
@@ -179,7 +177,6 @@ static void brush_painter_2d_require_imbuf(
       MEM_freeN(cache->tex_mask_old);
     }
     cache->ibuf = NULL;
-    cache->curve_mask = NULL;
     cache->tex_mask = NULL;
     cache->lastdiameter = -1; /* force ibuf create in refresh */
     cache->invert = invert;
@@ -200,9 +197,7 @@ static void brush_painter_cache_2d_free(BrushPainterCache *cache)
   if (cache->texibuf) {
     IMB_freeImBuf(cache->texibuf);
   }
-  if (cache->curve_mask) {
-    MEM_freeN(cache->curve_mask);
-  }
+  paint_curve_mask_cache_free_data(&cache->curve_mask_cache);
   if (cache->tex_mask) {
     MEM_freeN(cache->tex_mask);
   }
@@ -380,92 +375,6 @@ static void brush_painter_mask_imbuf_partial_update(BrushPainter *painter,
   cache->tex_mask_old_h = diameter;
 }
 
-/* create a mask with the falloff strength */
-static ushort *brush_painter_curve_mask_init(
-    ushort *mask, BrushPainter *painter, int diameter, float radius, const float pos[2])
-{
-  BLI_assert_msg(MEM_allocN_len(mask) == diameter * diameter * sizeof(ushort),
-                 "Allocated size of mask doesn't match.");
-
-  Brush *brush = painter->brush;
-
-  int offset = (int)floorf(diameter / 2.0f);
-
-  ushort *m;
-  m = mask;
-
-  int aa_samples = 1.0f / (radius * 0.20f);
-  if (brush->sampling_flag & BRUSH_PAINT_ANTIALIASING) {
-    aa_samples = clamp_i(aa_samples, 3, 16);
-  }
-  else {
-    aa_samples = 1;
-  }
-
-  /* Temporal until we have the brush properties */
-  const float hardness = 1.0f;
-  const float rotation = 0.0f;
-
-  float aa_offset = 1.0f / (2.0f * (float)aa_samples);
-  float aa_step = 1.0f / (float)aa_samples;
-
-  float bpos[2];
-  bpos[0] = pos[0] - floorf(pos[0]) + offset - aa_offset;
-  bpos[1] = pos[1] - floorf(pos[1]) + offset - aa_offset;
-
-  const float co = cosf(DEG2RADF(rotation));
-  const float si = sinf(DEG2RADF(rotation));
-
-  float norm_factor = 65535.0f / (float)(aa_samples * aa_samples);
-
-  for (int y = 0; y < diameter; y++) {
-    for (int x = 0; x < diameter; x++, m++) {
-      float total_samples = 0;
-      for (int i = 0; i < aa_samples; i++) {
-        for (int j = 0; j < aa_samples; j++) {
-          float pixel_xy[2] = {x + (aa_step * i), y + (aa_step * j)};
-          float xy_rot[2];
-          sub_v2_v2(pixel_xy, bpos);
-
-          xy_rot[0] = co * pixel_xy[0] - si * pixel_xy[1];
-          xy_rot[1] = si * pixel_xy[0] + co * pixel_xy[1];
-
-          float len = len_v2(xy_rot);
-          float p = len / radius;
-          if (hardness < 1.0f) {
-            p = (p - hardness) / (1.0f - hardness);
-            p = 1.0f - p;
-            CLAMP(p, 0.0f, 1.0f);
-          }
-          else {
-            p = 1.0;
-          }
-          float hardness_factor = 3.0f * p * p - 2.0f * p * p * p;
-          float curve = BKE_brush_curve_strength_clamped(brush, len, radius);
-          total_samples += curve * hardness_factor;
-        }
-      }
-      *m = (ushort)(total_samples * norm_factor);
-    }
-  }
-
-  return mask;
-}
-
-static void brush_painter_curve_mask_refresh(
-    BrushPainter *painter, ImagePaintTile *tile, int diameter, float radius, const float pos[2])
-{
-  BrushPainterCache *cache = &tile->cache;
-
-  if (diameter != cache->lastdiameter) {
-    if (cache->curve_mask != NULL) {
-      MEM_freeN(cache->curve_mask);
-    }
-    cache->curve_mask = MEM_mallocN(sizeof(ushort) * diameter * diameter, "brush_painter_mask");
-  }
-  brush_painter_curve_mask_init(cache->curve_mask, painter, diameter, radius, pos);
-}
-
 /* create imbuf with brush color */
 static ImBuf *brush_painter_imbuf_new(
     BrushPainter *painter, ImagePaintTile *tile, const int size, float pressure, float distance)
@@ -872,7 +781,7 @@ static void brush_painter_2d_refresh_cache(ImagePaintState *s,
   }
 
   /* Re-initialize the curve mask. Mask is always recreated due to the change of position. */
-  brush_painter_curve_mask_refresh(painter, tile, diameter, size, pos);
+  paint_curve_mask_cache_update(&cache->curve_mask_cache, brush, diameter, size, pos);
 
   /* detect if we need to recreate image brush buffer */
   if (diameter != cache->lastdiameter || (tex_rotation != cache->last_tex_rotation) || do_random ||
@@ -1336,7 +1245,7 @@ static void paint_2d_do_making_brush(ImagePaintState *s,
                     &tmpbuf,
                     frombuf,
                     mask,
-                    tile->cache.curve_mask,
+                    tile->cache.curve_mask_cache.curve_mask,
                     tile->cache.tex_mask,
                     mask_max,
                     region->destx,
@@ -1485,7 +1394,7 @@ static int paint_2d_op(void *state,
                              canvas,
                              frombuf,
                              NULL,
-                             tile->cache.curve_mask,
+                             tile->cache.curve_mask_cache.curve_mask,
                              tile->cache.tex_mask,
                              mask_max,
                              region[a].destx,