submodule/src/bones/weight.cpp

   1 #include "bones/weight.hpp"
   2 #include "container_component.hpp"
   3 #include "shapes/path_vertex.hpp"
   4
   5 using namespace rive;
   6
   7 StatusCode Weight::onAddedDirty(CoreContext* context)
   8 {
   9         StatusCode code = Super::onAddedDirty(context);
  10         if (code != StatusCode::Ok)
  11         {
  12                 return code;
  13         }
  14         if (!parent()->is<PathVertex>())
  15         {
  16                 return StatusCode::MissingObject;
  17         }
  18
  19         parent()->as<PathVertex>()->weight(this);
  20
  21         return StatusCode::Ok;
  22 }
  23
  24 static int encodedWeightValue(unsigned int index, unsigned int data)
  25 {
  26         return (data >> (index * 8)) & 0xFF;
  27 }
  28
  29 void Weight::deform(float x,
  30                     float y,
  31                     unsigned int indices,
  32                     unsigned int weights,
  33                     const Mat2D& world,
  34                     const float* boneTransforms,
  35                     Vec2D& result)
  36 {
  37         float xx = 0, xy = 0, yx = 0, yy = 0, tx = 0, ty = 0;
  38         float rx = world[0] * x + world[2] * y + world[4];
  39         float ry = world[1] * x + world[3] * y + world[5];
  40         for (int i = 0; i < 4; i++)
  41         {
  42                 int weight = encodedWeightValue(i, weights);
  43                 if (weight == 0)
  44                 {
  45                         continue;
  46                 }
  47
  48                 float normalizedWeight = weight / 255.0f;
  49                 int index = encodedWeightValue(i, indices);
  50                 int startBoneTransformIndex = index * 6;
  51                 xx += boneTransforms[startBoneTransformIndex++] * normalizedWeight;
  52                 xy += boneTransforms[startBoneTransformIndex++] * normalizedWeight;
  53                 yx += boneTransforms[startBoneTransformIndex++] * normalizedWeight;
  54                 yy += boneTransforms[startBoneTransformIndex++] * normalizedWeight;
  55                 tx += boneTransforms[startBoneTransformIndex++] * normalizedWeight;
  56                 ty += boneTransforms[startBoneTransformIndex++] * normalizedWeight;
  57         }
  58         result[0] = xx * rx + yx * ry + tx;
  59         result[1] = xy * rx + yy * ry + ty;
  60 }