[Bf-blender-cvs] [b49f0f990b5] cycles_procedural_api: first pass at reading arbitrary attributes

[Kévin Dietrich]

Commit: b49f0f990b51aefbf752fa998e61cfebaf801ca9
Author: Kévin Dietrich
Date:   Sun Sep 27 20:52:19 2020 +0200
Branches: cycles_procedural_api
https://developer.blender.org/rBb49f0f990b51aefbf752fa998e61cfebaf801ca9

first pass at reading arbitrary attributes

For now, we only read vertex colors.

===================================================================

M	intern/cycles/render/alembic.cpp
M	intern/cycles/render/alembic.h

===================================================================

diff --git a/intern/cycles/render/alembic.cpp b/intern/cycles/render/alembic.cpp
index 70e0053cdd8..58fbad0cf31 100644
--- a/intern/cycles/render/alembic.cpp
+++ b/intern/cycles/render/alembic.cpp
@@ -166,11 +166,27 @@ void AlembicObject::load_all_data(IPolyMeshSchema &schema)
   frame_data.clear();
 
   // TODO : store other properties and have a better structure to store these arrays
+  auto geometry_ = object->get_geometry();
+
+  AttributeRequestSet requested_attributes;
+
+  foreach (Node *node, geometry_->get_used_shaders()) {
+    Shader *shader = static_cast<Shader *>(node);
+
+    foreach (const AttributeRequest &attr, shader->attributes.requests) {
+      if (attr.name != "") {
+        requested_attributes.add(attr.name);
+      }
+    }
+  }
+
   for (size_t i = 0; i < schema.getNumSamples(); ++i) {
     frame_data.emplace_back();
     AlembicObject::DataCache &data_cache = frame_data.back();
 
-    auto sample = schema.getValue(ISampleSelector(static_cast<index_t>(i)));
+    ISampleSelector iss = ISampleSelector(static_cast<index_t>(i));
+
+    auto sample = schema.getValue(iss);
 
     auto positions = sample.getPositions();
 
@@ -211,11 +227,75 @@ void AlembicObject::load_all_data(IPolyMeshSchema &schema)
         index_offset += face_counts_array[i];
       }
     }
+
+    foreach (const AttributeRequest &attr, requested_attributes.requests) {
+      read_attribute(schema.getArbGeomParams(), iss, attr.name, data_cache);
+    }
   }
 
   data_loaded = true;
 }
 
+void AlembicObject::read_attribute(const ICompoundProperty &arb_geom_params, const ISampleSelector &iss, const ustring &attr_name, DataCache &data_cache)
+{
+  for (size_t i = 0; i < arb_geom_params.getNumProperties(); ++i) {
+    const PropertyHeader &prop = arb_geom_params.getPropertyHeader(i);
+
+    if (prop.getName() != attr_name) {
+      continue;
+    }
+
+    if (IV2fProperty::matches(prop.getMetaData()) && Alembic::AbcGeom::isUV(prop)) {
+      // TODO : UV indices
+//      const IV2fGeomParam &param = IV2fGeomParam(arb_geom_params, prop.getName());
+
+//      IV2fGeomParam::Sample sample;
+//      param.getIndexed(sample, iss);
+
+//      if (param.getScope() == kFacevaryingScope) {
+//        V2fArraySamplePtr values = sample.getVals();
+//        UInt32ArraySamplePtr indices = sample.getIndices();
+
+//        AttributeData &attribute = data_cache.attributes.emplace_back();
+//        attribute.name = attr_name;
+//        attribute.std = ATTR_STD_UV;
+//      }
+    }
+    else if (IC3fProperty::matches(prop.getMetaData())) {
+      const IC3fGeomParam &param = IC3fGeomParam(arb_geom_params, prop.getName());
+
+      IC3fGeomParam::Sample sample;
+      param.getIndexed(sample, iss);
+
+      C3fArraySamplePtr values = sample.getVals();
+
+      AttributeData &attribute = data_cache.attributes.emplace_back();
+      attribute.name = attr_name;
+
+      if (param.getScope() == kVaryingScope) {
+        attribute.std = ATTR_STD_VERTEX_COLOR;
+        attribute.data.resize(data_cache.triangles.size() * 3 * sizeof(uchar4));
+
+        uchar4 *data_uchar4 = reinterpret_cast<uchar4 *>(attribute.data.data());
+
+        int offset = 0;
+        for (const int3 &tri : data_cache.triangles) {
+          auto v = (*values)[tri.x];
+          data_uchar4[offset + 0] = color_float_to_byte(make_float3(v.x, v.y, v.z));
+
+          v = (*values)[tri.y];
+          data_uchar4[offset + 1] = color_float_to_byte(make_float3(v.x, v.y, v.z));
+
+          v = (*values)[tri.z];
+          data_uchar4[offset + 2] = color_float_to_byte(make_float3(v.x, v.y, v.z));
+
+          offset += 3;
+        }
+      }
+    }
+  }
+}
+
 NODE_DEFINE(AlembicProcedural)
 {
   NodeType *type = NodeType::add("alembic", create);
@@ -432,6 +512,11 @@ void AlembicProcedural::read_mesh(Scene *scene,
         attr->data_float3(), mesh->get_verts().data(), sizeof(float3) * mesh->get_verts().size());
   }
 
+  for (const AlembicObject::AttributeData &attribute : data.attributes) {
+    auto attr = mesh->attributes.add(attribute.std, attribute.name);
+    memcpy(attr->data_uchar4(), attribute.data.data(), attribute.data.size());
+  }
+
   if (mesh->is_modified()) {
     // TODO : check for modification of subdivision data (is a separate object in Alembic)
     bool need_rebuild = mesh->triangles_is_modified();
diff --git a/intern/cycles/render/alembic.h b/intern/cycles/render/alembic.h
index 52cd2dc59cf..14e98765b29 100644
--- a/intern/cycles/render/alembic.h
+++ b/intern/cycles/render/alembic.h
@@ -17,6 +17,7 @@
 #pragma once
 
 #include "graph/node.h"
+#include "render/attribute.h"
 #include "render/procedural.h"
 #include "util/util_transform.h"
 #include "util/util_vector.h"
@@ -53,10 +54,19 @@ class AlembicObject : public Node {
 
   // TODO : this is only for Meshes at the moment
   // TODO : handle attributes as well
+
+  struct AttributeData {
+      AttributeStandard std;
+      ustring name;
+      array<char> data;
+  };
+
   struct DataCache {
     bool dirty = false;
     array<float3> vertices{};
     array<int3> triangles{};
+
+    vector<AttributeData> attributes{};
   };
 
   DataCache &get_frame_data(int index);
@@ -72,6 +82,8 @@ class AlembicObject : public Node {
   bool data_loaded = false;
 
   vector<DataCache> frame_data;
+
+  void read_attribute(const ICompoundProperty &arb_geom_params, const ISampleSelector &iss, const ustring &attr_name, DataCache &data_cache);
 };
 
 class AlembicProcedural : public Procedural {