Modifiers: Add option to directly specify a 2D transform for UVWarp

Currently the only option is to warp based on the transform of other
objects, which is inconvenient if you want to e.g. control it through
a driver - you need to set up a dummy object and go through that,
which is clunky and should be unneccessary.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D6690

6 files changed, 90 insertions, 39 deletions

diff --git a/source/blender/blenlib/BLI_math_matrix.h b/source/blender/blenlib/BLI_math_matrix.h
index ac0f5f44c74..acefe18fd40 100644
--- a/source/blender/blenlib/BLI_math_matrix.h
+++ b/source/blender/blenlib/BLI_math_matrix.h
@@ -60,6 +60,9 @@ void copy_m4d_m4(double R[4][4], const float A[4][4]);
 void swap_m3m3(float A[3][3], float B[3][3]);
 void swap_m4m4(float A[4][4], float B[4][4]);
 
+/* Build index shuffle matrix */
+void shuffle_m4(float R[4][4], int index[4]);
+
 /******************************** Arithmetic *********************************/
 
 void add_m3_m3m3(float R[3][3], const float A[3][3], const float B[3][3]);
diff --git a/source/blender/blenlib/intern/math_matrix.c b/source/blender/blenlib/intern/math_matrix.c
index 4d8a2f72eca..86a08a42247 100644
--- a/source/blender/blenlib/intern/math_matrix.c
+++ b/source/blender/blenlib/intern/math_matrix.c
@@ -210,6 +210,16 @@ void swap_m4m4(float m1[4][4], float m2[4][4])
   }
 }
 
+void shuffle_m4(float R[4][4], int index[4])
+{
+  zero_m4(R);
+  for (int k = 0; k < 4; k++) {
+    if (index[k] >= 0) {
+      R[index[k]][k] = 1.0f;
+    }
+  }
+}
+
 /******************************** Arithmetic *********************************/
 
 void mul_m4_m4m4(float R[4][4], const float A[4][4], const float B[4][4])
diff --git a/source/blender/blenloader/intern/versioning_280.c b/source/blender/blenloader/intern/versioning_280.c
index 886c7195d9e..8baea5c8c4b 100644
--- a/source/blender/blenloader/intern/versioning_280.c
+++ b/source/blender/blenloader/intern/versioning_280.c
@@ -4482,5 +4482,17 @@ void blo_do_versions_280(FileData *fd, Library *UNUSED(lib), Main *bmain)
         }
       }
     }
+
+    /* Add 2D transform to UV Warp modifier. */
+    if (!DNA_struct_elem_find(fd->filesdna, "UVWarpModifierData", "float", "scale[2]")) {
+      for (Object *ob = bmain->objects.first; ob; ob = ob->id.next) {
+        for (ModifierData *md = ob->modifiers.first; md; md = md->next) {
+          if (md->type == eModifierType_UVWarp) {
+            UVWarpModifierData *umd = (UVWarpModifierData *)md;
+            copy_v2_fl(umd->scale, 1.0f);
+          }
+        }
+      }
+    }
   }
 }
diff --git a/source/blender/makesdna/DNA_modifier_types.h b/source/blender/makesdna/DNA_modifier_types.h
index 82237a10d23..7a61118921d 100644
--- a/source/blender/makesdna/DNA_modifier_types.h
+++ b/source/blender/makesdna/DNA_modifier_types.h
@@ -1742,10 +1742,14 @@ typedef struct UVWarpModifierData {
   ModifierData modifier;
 
   char axis_u, axis_v;
-  char _pad[6];
+  char _pad[2];
   /** Used for rotate/scale. */
   float center[2];
 
+  float offset[2];
+  float scale[2];
+  float rotation;
+
   /** Source. */
   struct Object *object_src;
   /** Optional name of bone target, MAX_ID_NAME-2. */
diff --git a/source/blender/makesrna/intern/rna_modifier.c b/source/blender/makesrna/intern/rna_modifier.c
index eb88f4523ab..ea0f917ca77 100644
--- a/source/blender/makesrna/intern/rna_modifier.c
+++ b/source/blender/makesrna/intern/rna_modifier.c
@@ -4599,6 +4599,21 @@ static void rna_def_modifier_uvwarp(BlenderRNA *brna)
   RNA_def_property_ui_text(prop, "UV Center", "Center point for rotate/scale");
   RNA_def_property_update(prop, 0, "rna_Modifier_update");
 
+  prop = RNA_def_property(srna, "offset", PROP_FLOAT, PROP_NONE);
+  RNA_def_property_float_sdna(prop, NULL, "offset");
+  RNA_def_property_ui_text(prop, "Offset", "2D Offset for the warp");
+  RNA_def_property_update(prop, 0, "rna_Modifier_update");
+
+  prop = RNA_def_property(srna, "scale", PROP_FLOAT, PROP_NONE);
+  RNA_def_property_float_sdna(prop, NULL, "scale");
+  RNA_def_property_ui_text(prop, "Scale", "2D Scale for the warp");
+  RNA_def_property_update(prop, 0, "rna_Modifier_update");
+
+  prop = RNA_def_property(srna, "rotation", PROP_FLOAT, PROP_ANGLE);
+  RNA_def_property_float_sdna(prop, NULL, "rotation");
+  RNA_def_property_ui_text(prop, "Rotation", "2D Rotation for the warp");
+  RNA_def_property_update(prop, 0, "rna_Modifier_update");
+
   prop = RNA_def_property(srna, "object_from", PROP_POINTER, PROP_NONE);
   RNA_def_property_pointer_sdna(prop, NULL, "object_src");
   RNA_def_property_ui_text(prop, "Object From", "Object defining offset");
diff --git a/source/blender/modifiers/intern/MOD_uvwarp.c b/source/blender/modifiers/intern/MOD_uvwarp.c
index dd9787c3c0b..2dfb9031c38 100644
--- a/source/blender/modifiers/intern/MOD_uvwarp.c
+++ b/source/blender/modifiers/intern/MOD_uvwarp.c
@@ -38,18 +38,13 @@
 
 #include "MOD_util.h"
 
-static void uv_warp_from_mat4_pair(
-    float uv_dst[2], const float uv_src[2], float warp_mat[4][4], int axis_u, int axis_v)
+static void uv_warp_from_mat4_pair(float uv_dst[2], const float uv_src[2], float warp_mat[4][4])
 {
   float tuv[3] = {0.0f};
 
-  tuv[axis_u] = uv_src[0];
-  tuv[axis_v] = uv_src[1];
-
+  copy_v2_v2(tuv, uv_src);
   mul_m4_v3(warp_mat, tuv);
-
-  uv_dst[0] = tuv[axis_u];
-  uv_dst[1] = tuv[axis_v];
+  copy_v2_v2(uv_dst, tuv);
 }
 
 static void initData(ModifierData *md)
@@ -58,6 +53,7 @@ static void initData(ModifierData *md)
   umd->axis_u = 0;
   umd->axis_v = 1;
   copy_v2_fl(umd->center, 0.5f);
+  copy_v2_fl(umd->scale, 1.0f);
 }
 
 static void requiredDataMask(Object *UNUSED(ob),
@@ -92,8 +88,6 @@ typedef struct UVWarpData {
   int defgrp_index;
 
   float (*warp_mat)[4];
-  int axis_u;
-  int axis_v;
 } UVWarpData;
 
 static void uv_warp_compute(void *__restrict userdata,
@@ -110,8 +104,6 @@ static void uv_warp_compute(void *__restrict userdata,
   const int defgrp_index = data->defgrp_index;
 
   float(*warp_mat)[4] = data->warp_mat;
-  const int axis_u = data->axis_u;
-  const int axis_v = data->axis_v;
 
   int l;
 
@@ -120,13 +112,13 @@ static void uv_warp_compute(void *__restrict userdata,
       float uv[2];
       const float weight = defvert_find_weight(&dvert[ml->v], defgrp_index);
 
-      uv_warp_from_mat4_pair(uv, mluv->uv, warp_mat, axis_u, axis_v);
+      uv_warp_from_mat4_pair(uv, mluv->uv, warp_mat);
       interp_v2_v2v2(mluv->uv, mluv->uv, uv, weight);
     }
   }
   else {
     for (l = 0; l < mp->totloop; l++, ml++, mluv++) {
-      uv_warp_from_mat4_pair(mluv->uv, mluv->uv, warp_mat, axis_u, axis_v);
+      uv_warp_from_mat4_pair(mluv->uv, mluv->uv, warp_mat);
     }
   }
 }
@@ -141,9 +133,6 @@ static Mesh *applyModifier(ModifierData *md, const ModifierEvalContext *ctx, Mes
   MDeformVert *dvert;
   int defgrp_index;
   char uvname[MAX_CUSTOMDATA_LAYER_NAME];
-  float mat_src[4][4];
-  float mat_dst[4][4];
-  float imat_dst[4][4];
   float warp_mat[4][4];
   const int axis_u = umd->axis_u;
   const int axis_v = umd->axis_v;
@@ -152,32 +141,52 @@ static Mesh *applyModifier(ModifierData *md, const ModifierEvalContext *ctx, Mes
   if (!CustomData_has_layer(&mesh->ldata, CD_MLOOPUV)) {
     return mesh;
   }
-  else if (ELEM(NULL, umd->object_src, umd->object_dst)) {
-    modifier_setError(md, "From/To objects must be set");
-    return mesh;
-  }
 
-  /* make sure anything moving UVs is available */
-  matrix_from_obj_pchan(mat_src, umd->object_src, umd->bone_src);
-  matrix_from_obj_pchan(mat_dst, umd->object_dst, umd->bone_dst);
+  if (!ELEM(NULL, umd->object_src, umd->object_dst)) {
+    float mat_src[4][4];
+    float mat_dst[4][4];
+    float imat_dst[4][4];
+    float shuf_mat[4][4];
+
+    /* make sure anything moving UVs is available */
+    matrix_from_obj_pchan(mat_src, umd->object_src, umd->bone_src);
+    matrix_from_obj_pchan(mat_dst, umd->object_dst, umd->bone_dst);
 
-  invert_m4_m4(imat_dst, mat_dst);
-  mul_m4_m4m4(warp_mat, imat_dst, mat_src);
+    invert_m4_m4(imat_dst, mat_dst);
+    mul_m4_m4m4(warp_mat, imat_dst, mat_src);
 
-  /* apply warp */
-  if (!is_zero_v2(umd->center)) {
-    float mat_cent[4][4];
-    float imat_cent[4][4];
+    /* apply warp */
+    if (!is_zero_v2(umd->center)) {
+      float mat_cent[4][4];
+      float imat_cent[4][4];
 
-    unit_m4(mat_cent);
-    mat_cent[3][axis_u] = umd->center[0];
-    mat_cent[3][axis_v] = umd->center[1];
+      unit_m4(mat_cent);
+      mat_cent[3][axis_u] = umd->center[0];
+      mat_cent[3][axis_v] = umd->center[1];
 
-    invert_m4_m4(imat_cent, mat_cent);
+      invert_m4_m4(imat_cent, mat_cent);
 
-    mul_m4_m4m4(warp_mat, warp_mat, imat_cent);
-    mul_m4_m4m4(warp_mat, mat_cent, warp_mat);
+      mul_m4_m4m4(warp_mat, warp_mat, imat_cent);
+      mul_m4_m4m4(warp_mat, mat_cent, warp_mat);
+    }
+
+    int shuf_indices[4] = {axis_u, axis_v, -1, 3};
+    shuffle_m4(shuf_mat, shuf_indices);
+    mul_m4_m4m4(warp_mat, shuf_mat, warp_mat);
+    transpose_m4(shuf_mat);
+    mul_m4_m4m4(warp_mat, warp_mat, shuf_mat);
   }
+  else {
+    unit_m4(warp_mat);
+  }
+
+  /* Apply direct 2d transform. */
+  translate_m4(warp_mat, umd->center[0], umd->center[1], 0.0f);
+  const float scale[3] = {umd->scale[0], umd->scale[1], 1.0f};
+  rescale_m4(warp_mat, scale);
+  rotate_m4(warp_mat, 'Z', umd->rotation);
+  translate_m4(warp_mat, umd->offset[0], umd->offset[1], 0.0f);
+  translate_m4(warp_mat, -umd->center[0], -umd->center[1], 0.0f);
 
   /* make sure we're using an existing layer */
   CustomData_validate_layer_name(&mesh->ldata, CD_MLOOPUV, umd->uvlayer_name, uvname);
@@ -199,8 +208,6 @@ static Mesh *applyModifier(ModifierData *md, const ModifierEvalContext *ctx, Mes
       .dvert = dvert,
       .defgrp_index = defgrp_index,
       .warp_mat = warp_mat,
-      .axis_u = axis_u,
-      .axis_v = axis_v,
   };
   TaskParallelSettings settings;
   BLI_parallel_range_settings_defaults(&settings);