Fixed handling of PLY with vertex colors as uchar

libs/yocto/yocto_modelio.h

@@ -43,6 +43,7 @@
 #include <stdexcept>
 #include <string>
 #include <vector>
+#include <limits>
 
 // -----------------------------------------------------------------------------
 // USING DIRECTIVES
@@ -531,6 +532,24 @@ inline T get_value(const ply_property& prop, size_t index) {
   }
   return 0;
 }
+// Assumes T is a floating point type, and any integral type will be divided by
+// the max value of its type (matching behavior of Blender PLY import).
+template <typename T>
+inline T get_normalized_value(const ply_property& prop, size_t index) {
+  switch (prop.type) {
+    case ply_type::i8: return (T)prop.data_i8[index]/(T)std::numeric_limits<int8_t>::max();
+    case ply_type::i16: return (T)prop.data_i16[index]/(T)std::numeric_limits<int16_t>::max();
+    case ply_type::i32: return (T)prop.data_i32[index]/(T)std::numeric_limits<int32_t>::max();
+    case ply_type::i64: return (T)prop.data_i64[index]/(T)std::numeric_limits<int64_t>::max();
+    case ply_type::u8: return (T)prop.data_u8[index]/(T)std::numeric_limits<uint8_t>::max();
+    case ply_type::u16: return (T)prop.data_u16[index]/(T)std::numeric_limits<uint16_t>::max();
+    case ply_type::u32: return (T)prop.data_u32[index]/(T)std::numeric_limits<uint32_t>::max();
+    case ply_type::u64: return (T)prop.data_u64[index]/(T)std::numeric_limits<uint64_t>::max();
+    case ply_type::f32: return (T)prop.data_f32[index];
+    case ply_type::f64: return (T)prop.data_f64[index];
+  }
+  return 0;
+}
 template <typename T>
 inline bool get_value(const ply_model& ply, const string& element,
     const string& property, vector<T>& values) {
@@ -546,7 +565,7 @@ inline bool get_value(const ply_model& ply, const string& element,
 }
 template <typename T, size_t N>
 inline bool get_values(const ply_model& ply, const string& element,
-    const array<string, N>& properties, vector<array<T, N>>& values) {
+    const array<string, N>& properties, bool normalize, vector<array<T, N>>& values) {
   values.clear();
   for (auto& property : properties) {
     if (!has_property(ply, element, property)) return false;
@@ -558,12 +577,21 @@ inline bool get_values(const ply_model& ply, const string& element,
   for (auto& property : properties) {
     auto& prop = get_property(ply, element, property);
     for (auto index = (size_t)0; index < values.size(); index++) {
-      values[index][item] = get_value<T>(prop, index);
+      if(normalize) {
+        values[index][item] = get_normalized_value<T>(prop, index);
+      } else {
+        values[index][item] = get_value<T>(prop, index);
+      }
     }
     item++;
   }
   return true;
 }
+template <typename T, size_t N>
+inline bool get_values(const ply_model& ply, const string& element,
+    const array<string, N>& properties, vector<array<T, N>>& values) {
+  return get_values(ply, element, properties, /* normalize */ false, values);
+}
 
 template <typename T>
 inline bool get_lists(const ply_model& ply, const string& element,
@@ -766,15 +794,15 @@ inline bool get_texcoords(
 }
 template <typename T>
 inline bool get_colors(const ply_model& ply, vector<array<T, 3>>& colors) {
-  return get_values(ply, "vertex", {"red", "green", "blue"}, colors);
+  return get_values(ply, "vertex", {"red", "green", "blue"}, /* normalize */ true, colors);
 }
 template <typename T>
 inline bool get_colors(const ply_model& ply, vector<array<T, 4>>& colors) {
   if (has_property(ply, "vertex", "alpha")) {
-    return get_values(ply, "vertex", {"red", "green", "blue", "alpha"}, colors);
+    return get_values(ply, "vertex", {"red", "green", "blue", "alpha"}, /* normalize */ true, colors);
   } else {
     auto colors3 = vector<array<T, 3>>{};
-    if (!get_values(ply, "vertex", {"red", "green", "blue"}, colors3))
+    if (!get_values(ply, "vertex", {"red", "green", "blue"}, /* normalize */ true, colors3))
       return false;
     colors.resize(colors3.size());
     for (auto i = 0; i < (int)colors.size(); i++)

tests/materials5/materials5.json

@@ -0,0 +1,195 @@
+{
+  "asset": {
+    "copyright": "Model by Fabio Pellacini from github.com/~xelatihy/yocto-gl",
+    "generator": "Yocto/GL - https://github.com/xelatihy/yocto-gl",
+    "version": "4.2"
+  },
+  "cameras": [
+    {
+      "name": "default",
+      "frame": [
+        0.8151804208755493,
+        -0.0,
+        0.579207181930542,
+        0.16660168766975403,
+        0.9577393531799316,
+        -0.23447643220424652,
+        -0.5547295212745667,
+        0.28763750195503235,
+        0.7807304263114929,
+        -0.75,
+        0.4000000059604645,
+        0.8999999761581421
+      ],
+      "aspect": 2.4000000953674316,
+      "focus": 1.2168092727661133
+    }
+  ],
+  "environments": [
+    {
+      "name": "sky",
+      "emission": [
+        0.5,
+        0.5,
+        0.5
+      ],
+      "emission_tex": 0
+    }
+  ],
+  "textures": [
+    {
+      "name": "sky",
+      "uri": "textures/sky.hdr"
+    },
+    {
+      "name": "floor",
+      "uri": "textures/floor.png"
+    }
+  ],
+  "shapes": [
+    {
+      "name": "arealight1",
+      "uri": "shapes/arealight1.ply"
+    },
+    {
+      "name": "arealight2",
+      "uri": "shapes/arealight2.ply"
+    },
+    {
+      "name": "floor",
+      "uri": "shapes/floor.ply"
+    },
+    {
+      "name": "sphere_with_uchar_vertex_colors",
+      "uri": "shapes/sphere_vertex_colors_uchar.ply"
+    }
+  ],
+  "subdivs": [],
+  "materials": [
+    {
+      "name": "arealight1",
+      "type": "matte",
+      "emission": [
+        20,
+        20,
+        20
+      ],
+      "color": [
+        0,
+        0,
+        0
+      ]
+    },
+    {
+      "name": "arealight2",
+      "type": "matte",
+      "emission": [
+        20,
+        20,
+        20
+      ],
+      "color": [
+        0,
+        0,
+        0
+      ]
+    },
+    {
+      "name": "floor",
+      "type": "matte",
+      "color": [
+        1,
+        1,
+        1
+      ],
+      "color_tex": 1
+    },
+    {
+      "name": "vertexcolors",
+      "type": "matte",
+      "color": [
+        1,
+        1,
+        1
+      ]
+    }
+  ],
+  "instances": [
+    {
+      "name": "arealight1",
+      "frame": [
+        0.8944271802902222,
+        -0.0,
+        0.4472135901451111,
+        0.27562475204467773,
+        0.7874992489814758,
+        -0.5512495040893555,
+        -0.3521803617477417,
+        0.6163156628608704,
+        0.7043607234954834,
+        -0.4000000059604645,
+        0.800000011920929,
+        0.800000011920929
+      ],
+      "shape": 0,
+      "material": 0
+    },
+    {
+      "name": "arealight2",
+      "frame": [
+        0.8944271802902222,
+        0.0,
+        -0.4472135901451111,
+        -0.27562475204467773,
+        0.7874992489814758,
+        -0.5512495040893555,
+        0.3521803617477417,
+        0.6163156628608704,
+        0.7043607234954834,
+        0.4000000059604645,
+        0.800000011920929,
+        0.800000011920929
+      ],
+      "shape": 1,
+      "material": 1
+    },
+    {
+      "name": "floor",
+      "frame": [
+        1,
+        0,
+        0,
+        0,
+        1,
+        0,
+        0,
+        0,
+        1,
+        0,
+        0,
+        0
+      ],
+      "shape": 2,
+      "material": 2
+    },
+    {
+      "name": "sphere",
+      "frame": [
+        1,
+        0,
+        0,
+        0,
+        1,
+        0,
+        0,
+        0,
+        1,
+        -0.4,
+        0,
+        0
+      ],
+      "shape": 3,
+      "material": 3
+    }
+  ]
+}