add custom-models in hand support

src/graphics/render/ModelsGenerator.cpp

@@ -1,6 +1,7 @@
 #include "ModelsGenerator.hpp"
 
 #include "assets/Assets.hpp"
+#include "assets/assets_util.hpp"
 #include "items/ItemDef.hpp"
 #include "voxels/Block.hpp"
 #include "content/Content.hpp"
@@ -40,6 +41,13 @@ static model::Model create_flat_model(
     return model;
 }
 
+static inline UVRegion get_region_for(
+    const std::string& texture, const Assets& assets
+) {
+    auto texreg = util::get_texture_region(assets, "blocks:" + texture, "");
+    return texreg.region;
+}
+
 model::Model ModelsGenerator::generate(
     const ItemDef& def, const Content& content, const Assets& assets
 ) {
@@ -50,6 +58,56 @@ model::Model ModelsGenerator::generate(
             return create_flat_model(
                 "blocks:" + blockDef.textureFaces.at(0), assets
             );
+        } else if (blockDef.model == BlockModel::custom) {
+            model = model::Model();
+            for (size_t i = 0; i < blockDef.modelBoxes.size(); i++) {
+                auto& mesh =
+                    model.addMesh("blocks:" + blockDef.modelTextures[i * 6]);
+                mesh.lighting = !def.rt.emissive;
+                const UVRegion (&boxtexfaces)[6] = {
+                    get_region_for(blockDef.modelTextures[i * 6], assets),
+                    get_region_for(blockDef.modelTextures[i * 6 + 1], assets),
+                    get_region_for(blockDef.modelTextures[i * 6 + 2], assets),
+                    get_region_for(blockDef.modelTextures[i * 6 + 3], assets),
+                    get_region_for(blockDef.modelTextures[i * 6 + 4], assets),
+                    get_region_for(blockDef.modelTextures[i * 6 + 5], assets)
+                };
+                mesh.addBox(
+                    blockDef.modelBoxes[i].center(),
+                    blockDef.modelBoxes[i].size()*0.5f, boxtexfaces
+                );
+            }
+            const auto& points = blockDef.modelExtraPoints;
+            glm::vec3 poff = glm::vec3(0.0f, 0.0f, 1.0f);
+            glm::vec3 norm {0, 1, 0};
+            for (size_t i = 0; i < blockDef.modelExtraPoints.size() / 4; i++) {
+                auto texture =
+                    "blocks:" +
+                    blockDef.modelTextures[blockDef.modelBoxes.size() * 6 + i];
+                    
+                auto& mesh = model.addMesh(texture);
+                mesh.lighting = !def.rt.emissive;
+
+                auto reg = get_region_for(texture, assets);
+                mesh.vertices.push_back(
+                    {points[i * 4 + 0] - poff, glm::vec2(reg.u1, reg.v1), norm}
+                );
+                mesh.vertices.push_back(
+                    {points[i * 4 + 1] - poff, glm::vec2(reg.u2, reg.v1), norm}
+                );
+                mesh.vertices.push_back(
+                    {points[i * 4 + 2] - poff, glm::vec2(reg.u2, reg.v2), norm}
+                );
+                mesh.vertices.push_back(
+                    {points[i * 4 + 3] - poff, glm::vec2(reg.u1, reg.v1), norm}
+                );
+                mesh.vertices.push_back(
+                    {points[i * 4 + 4] - poff, glm::vec2(reg.u2, reg.v2), norm}
+                );
+                mesh.vertices.push_back(
+                    {points[i * 4 + 0] - poff, glm::vec2(reg.u1, reg.v2), norm}
+                );
+            }
         }
         for (auto& mesh : model.meshes) {
             switch (blockDef.model) {