Painting: Performance curve masks.

This patch separates the static-part from the dynamic-part when
generate brush masks. This makes the generation of brush masks 2-5 times
faster depending on the size of the brush.

More improvements can be done, this was just low hanging fruit.

1 files changed, 12 insertions, 0 deletions

diff --git a/source/blender/editors/sculpt_paint/paint_intern.h b/source/blender/editors/sculpt_paint/paint_intern.h
index 13ae2b34860..62320defbb3 100644
--- a/source/blender/editors/sculpt_paint/paint_intern.h
+++ b/source/blender/editors/sculpt_paint/paint_intern.h
@@ -258,6 +258,18 @@ void PAINT_OT_add_simple_uvs(struct wmOperatorType *ot);
  */
 typedef struct CurveMaskCache {
   /**
+   * \brief Last #CurveMapping.changed_timestamp being read.
+   *
+   * When different the input cache needs to be recalculated.
+   */
+  int last_curve_timestamp;
+
+  /**
+   * \brief sampled version of the brush curvemapping.
+   */
+  float *sampled_curve;
+
+  /**
    * \brief Size in bytes of the curve_mask field.
    *
    * Used to determine if the curve_mask needs to be re-allocated.