GPencil: Refactor of Draw Engine, Vertex Paint and all internal functions

This commit is a full refactor of the grease pencil modules including Draw Engine, Modifiers, VFX, depsgraph update, improvements in operators and conversion of Sculpt and Weight paint tools to real brushes.

Also, a huge code cleanup has been done at all levels.

Thanks to @fclem for his work and yo @pepeland and @mendio for the testing and help in the development.

Differential Revision: https://developer.blender.org/D6293

1 files changed, 25 insertions, 54 deletions

diff --git a/source/blender/gpencil_modifiers/intern/MOD_gpencilthick.c b/source/blender/gpencil_modifiers/intern/MOD_gpencilthick.c
index 694b932a6bf..894dff46ac2 100644
--- a/source/blender/gpencil_modifiers/intern/MOD_gpencilthick.c
+++ b/source/blender/gpencil_modifiers/intern/MOD_gpencilthick.c
@@ -23,6 +23,8 @@
 
 #include <stdio.h>
 
+#include "BLI_listbase.h"
+#include "BLI_math.h"
 #include "BLI_utildefines.h"
 
 #include "DNA_meshdata_types.h"
@@ -45,7 +47,8 @@ static void initData(GpencilModifierData *md)
 {
   ThickGpencilModifierData *gpmd = (ThickGpencilModifierData *)md;
   gpmd->pass_index = 0;
-  gpmd->thickness = 2;
+  gpmd->thickness_fac = 1.0f;
+  gpmd->thickness = 30;
   gpmd->layername[0] = '\0';
   gpmd->materialname[0] = '\0';
   gpmd->vgname[0] = '\0';
@@ -105,70 +108,38 @@ static void deformStroke(GpencilModifierData *md,
     return;
   }
 
-  /* Check to see if we normalize the whole stroke or only certain points along it. */
-  bool gps_has_affected_points = false;
-  bool gps_has_unaffected_points = false;
-
-  if (mmd->flag & GP_THICK_NORMALIZE) {
-    for (int i = 0; i < gps->totpoints; i++) {
-      MDeformVert *dvert = gps->dvert != NULL ? &gps->dvert[i] : NULL;
-      const float weight = get_modifier_point_weight(
-          dvert, (mmd->flag & GP_THICK_INVERT_VGROUP) != 0, def_nr);
-      if (weight < 0.0f) {
-        gps_has_unaffected_points = true;
-      }
-      else {
-        gps_has_affected_points = true;
-      }
-
-      /* If both checks are true, we have what we need so we can stop looking. */
-      if (gps_has_affected_points && gps_has_unaffected_points) {
-        break;
-      }
-    }
-  }
-
-  /* If we are normalizing and all points of the stroke are affected, it's safe to reset thickness
-   */
-  if (mmd->flag & GP_THICK_NORMALIZE && gps_has_affected_points && !gps_has_unaffected_points) {
-    gps->thickness = mmd->thickness;
-  }
-  /* Without this check, modifier alters the thickness of strokes which have no points in scope */
+  float stroke_thickness_inv = 1.0f / max_ii(gps->thickness, 1);
 
   for (int i = 0; i < gps->totpoints; i++) {
     bGPDspoint *pt = &gps->points[i];
     MDeformVert *dvert = gps->dvert != NULL ? &gps->dvert[i] : NULL;
-    float curvef = 1.0f;
     /* Verify point is part of vertex group. */
-    const float weight = get_modifier_point_weight(
+    float weight = get_modifier_point_weight(
         dvert, (mmd->flag & GP_THICK_INVERT_VGROUP) != 0, def_nr);
     if (weight < 0.0f) {
       continue;
     }
 
+    float curvef = 1.0f;
+    if ((mmd->flag & GP_THICK_CUSTOM_CURVE) && (mmd->curve_thickness)) {
+      /* Normalize value to evaluate curve. */
+      float value = (float)i / (gps->totpoints - 1);
+      curvef = BKE_curvemapping_evaluateF(mmd->curve_thickness, 0, value);
+    }
+
+    float target;
     if (mmd->flag & GP_THICK_NORMALIZE) {
-      if (gps_has_unaffected_points) {
-        /* Clamp value for very weird situations when stroke thickness can be zero. */
-        CLAMP_MIN(gps->thickness, 1);
-        /* Calculate pressure value to match the width of strokes with reset thickness and 1.0
-         * pressure. */
-        pt->pressure = (float)mmd->thickness / (float)gps->thickness;
-      }
-      else {
-        /* Reset point pressure values so only stroke thickness counts. */
-        pt->pressure = 1.0f;
-      }
+      target = mmd->thickness * stroke_thickness_inv;
+      target *= curvef;
     }
     else {
-      if ((mmd->flag & GP_THICK_CUSTOM_CURVE) && (mmd->curve_thickness)) {
-        /* Normalize value to evaluate curve. */
-        float value = (float)i / (gps->totpoints - 1);
-        curvef = BKE_curvemapping_evaluateF(mmd->curve_thickness, 0, value);
-      }
-
-      pt->pressure += mmd->thickness * weight * curvef;
-      CLAMP_MIN(pt->pressure, 0.1f);
+      target = pt->pressure * mmd->thickness_fac;
+      weight *= curvef;
     }
+
+    pt->pressure = interpf(target, pt->pressure, weight);
+
+    CLAMP_MIN(pt->pressure, 0.1f);
   }
 }
 
@@ -179,9 +150,9 @@ static void bakeModifier(struct Main *UNUSED(bmain),
 {
   bGPdata *gpd = ob->data;
 
-  for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
-    for (bGPDframe *gpf = gpl->frames.first; gpf; gpf = gpf->next) {
-      for (bGPDstroke *gps = gpf->strokes.first; gps; gps = gps->next) {
+  LISTBASE_FOREACH (bGPDlayer *, gpl, &gpd->layers) {
+    LISTBASE_FOREACH (bGPDframe *, gpf, &gpl->frames) {
+      LISTBASE_FOREACH (bGPDstroke *, gps, &gpf->strokes) {
         deformStroke(md, depsgraph, ob, gpl, gpf, gps);
       }
     }