add ModelBuilder

src/coders/vcm.cpp

@@ -1,17 +1,19 @@
 #include "vcm.hpp"
 
-#include <algorithm>
-#include <glm/gtc/quaternion.hpp>
-#include <glm/gtc/matrix_transform.hpp>
-#include <glm/gtc/type_ptr.hpp>
-
 #include "xml.hpp"
 #include "util/stringutil.hpp"
 #include "graphics/commons/Model.hpp"
 #include "io/io.hpp"
 
+#include <vector>
+#include <algorithm>
+#include <glm/gtc/quaternion.hpp>
+#include <glm/gtc/matrix_transform.hpp>
+#include <glm/gtc/type_ptr.hpp>
+
 using namespace vcm;
 using namespace xml;
+using namespace model;
 
 static const std::unordered_map<std::string, int> side_indices {
     {"north", 0},
@@ -26,7 +28,87 @@ static bool to_boolean(const xml::Attribute& attr) {
     return attr.getText() != "off";
 }
 
-static void perform_rect(const xmlelement& root, model::Model& model) {
+class ModelBuilder {
+public:
+    ModelBuilder(Model& model) : model(model) {}
+
+    void push(const glm::mat4& matrix) {
+        matrices.push_back(matrix);
+        calculateMatrix();
+    }
+
+    void pop() {
+        matrices.pop_back();
+        calculateMatrix();
+    }
+
+    void addBox(
+        const std::string& texture,
+        bool shading,
+        const glm::vec3& pos,
+        const glm::vec3& size,
+        const UVRegion (&uvs)[6],
+        const bool enabledSides[6]
+    ) {
+        auto& mesh = model.addMesh(texture, shading);
+        mesh.addBox(pos, size, uvs, enabledSides, combined);
+    }
+
+    void addTriangle(
+        const std::string& texture,
+        bool shading,
+        const glm::vec3& a,
+        const glm::vec3& b,
+        const glm::vec3& c,
+        const glm::vec3& norm,
+        const glm::vec2& uvA,
+        const glm::vec2& uvB,
+        const glm::vec2& uvC
+    ) {
+        auto& mesh = model.addMesh(texture, shading);
+        mesh.addTriangle(
+            combined * glm::vec4(a, 1.0f),
+            combined * glm::vec4(b, 1.0f),
+            combined * glm::vec4(c, 1.0f),
+            norm,
+            uvA,
+            uvB,
+            uvC
+        );
+    }
+
+    void addRect(
+        const std::string& texture,
+        bool shading,
+        const glm::vec3& pos,
+        const glm::vec3& right,
+        const glm::vec3& up,
+        const glm::vec3& norm,
+        const UVRegion& uv
+    ) {
+        auto& mesh = model.addMesh(texture, shading);
+        mesh.addRect(pos, right, up, norm, uv, combined);
+    }
+
+    Model& getModel() {
+        return model;
+    }
+private:
+    void calculateMatrix() {
+        combined = glm::mat4(1.0f);
+        for (const auto& matrix : matrices) {
+            combined *= matrix;
+        }
+    }
+
+    Model& model;
+    std::vector<glm::mat4> matrices;
+    glm::mat4 combined {1.0f};
+};
+
+static void perform_element(const xmlelement& root, ModelBuilder& builder);
+
+static void perform_rect(const xmlelement& root, ModelBuilder& builder) {
     auto from = root.attr("from").asVec3();
     auto right = root.attr("right").asVec3();
     auto up = root.attr("up").asVec3();
@@ -60,10 +142,11 @@ static void perform_rect(const xmlelement& root, model::Model& model) {
         from -= up;
     }
     std::string texture = root.attr("texture", "$0").getText();
-    auto& mesh = model.addMesh(texture, shading);
 
     auto normal = glm::cross(glm::normalize(right), glm::normalize(up));
-    mesh.addRect(
+    builder.addRect(
+        texture,
+        shading,
         from + right * 0.5f + up * 0.5f,
         right * 0.5f,
         up * 0.5f,
@@ -72,7 +155,7 @@ static void perform_rect(const xmlelement& root, model::Model& model) {
     );
 }
 
-static void perform_triangle(const xmlelement& root, model::Model& model) {
+static void perform_triangle(const xmlelement& root, ModelBuilder& builder) {
     auto pointA = root.attr("a").asVec3();
     auto pointB = root.attr("b").asVec3();
     auto pointC = root.attr("c").asVec3();
@@ -104,11 +187,10 @@ static void perform_triangle(const xmlelement& root, model::Model& model) {
     }
     
     std::string texture = root.attr("texture", "$0").getText();
-    auto& mesh = model.addMesh(texture, shading);
-    mesh.addTriangle(pointA, pointB, pointC, normal, uvs[0], uvs[1], uvs[2]);
+    builder.addTriangle(texture, shading, pointA, pointB, pointC, normal, uvs[0], uvs[1], uvs[2]);
 }
 
-static void perform_box(const xmlelement& root, model::Model& model) {
+static void perform_box(const xmlelement& root, ModelBuilder& builder) {
     auto from = root.attr("from").asVec3();
     auto to = root.attr("to").asVec3();
 
@@ -186,7 +268,7 @@ static void perform_box(const xmlelement& root, model::Model& model) {
 
     bool deleted[6] {};
     if (root.has("delete")) {
-        // todo: replace by expression parsing
+        // todo: replace with expression parsing
         auto names = util::split(root.attr("delete").getText(), ',');
         for (auto& name : names) {
             util::trim(name);
@@ -197,30 +279,37 @@ static void perform_box(const xmlelement& root, model::Model& model) {
         }
     }
 
+    builder.push(tsf);
     for (int i = 0; i < 6; i++) {
         if (deleted[i]) {
             continue;
         }
         bool enabled[6] {};
         enabled[i] = true;
-        auto& mesh = model.addMesh(texfaces[i], shading);
-        mesh.addBox(center, halfsize, regions, enabled, tsf);
+
+        builder.addBox(texfaces[i], shading, center, halfsize, regions, enabled);
+    }
+    builder.pop();
+}
+
+static void perform_element(const xmlelement& root, ModelBuilder& builder) {
+    auto tag = root.getTag();
+
+    if (tag == "rect") {
+        perform_rect(root, builder);
+    } else if (tag == "box") {
+        perform_box(root, builder);
+    } else if (tag == "tri") {
+        perform_triangle(root, builder);
     }
 }
 
 static std::unique_ptr<model::Model> load_model(const xmlelement& root) {
-    model::Model model;
+    Model model;
+    ModelBuilder builder(model);
 
     for (const auto& elem : root.getElements()) {
-        auto tag = elem->getTag();
-
-        if (tag == "rect") {
-            perform_rect(*elem, model);
-        } else if (tag == "box") {
-            perform_box(*elem, model);
-        } else if (tag == "tri") {
-            perform_triangle(*elem, model);
-        }
+        perform_element(*elem, builder);
     }
 
     return std::make_unique<model::Model>(std::move(model));

src/graphics/commons/Model.cpp

@@ -1,6 +1,10 @@
+#define GLM_ENABLE_EXPERIMENTAL
+
 #include "Model.hpp"
 
 #include <algorithm>
+#include <glm/gtc/quaternion.hpp>
+#include <glm/gtx/matrix_decompose.hpp>
 
 using namespace model;
 
@@ -71,6 +75,39 @@ void Mesh::addRect(
     vertices.push_back({pos-right+up, {uv.u1, uv.v2}, norm});
 }
 
+static glm::mat4 extract_rotation(const glm::mat4& matrix) {
+    glm::vec3 scale;
+    glm::quat rotation;
+    glm::vec3 translation;
+    glm::vec3 skew;
+    glm::vec4 perspective;
+    glm::decompose(matrix, scale, rotation, translation, skew, perspective);
+    return glm::mat4_cast(rotation);
+}
+
+void Mesh::addRect(
+    const glm::vec3& pos,
+    const glm::vec3& right,
+    const glm::vec3& up,
+    const glm::vec3& norm,
+    const UVRegion& uv,
+    const glm::mat4& transform
+) {
+    auto a = transform * glm::vec4(pos - right - up, 1.0f);
+    auto b = transform * glm::vec4(pos + right - up, 1.0f);
+    auto c = transform * glm::vec4(pos + right + up, 1.0f);
+    auto d = transform * glm::vec4(pos - right + up, 1.0f);
+    auto tsfnorm = extract_rotation(transform) * glm::vec4(norm, 1.0f);
+
+    vertices.push_back({a, {uv.u1, uv.v1}, tsfnorm});
+    vertices.push_back({b, {uv.u2, uv.v1}, tsfnorm});
+    vertices.push_back({c, {uv.u2, uv.v2}, tsfnorm});
+
+    vertices.push_back({a, {uv.u1, uv.v1}, tsfnorm});
+    vertices.push_back({c, {uv.u2, uv.v2}, tsfnorm});
+    vertices.push_back({d, {uv.u1, uv.v2}, tsfnorm});
+}
+
 void Mesh::addBox(const glm::vec3& pos, const glm::vec3& size) {
     UVRegion fullRegion (0, 0, 1, 1);
     addPlane(pos+Z*size, X*size, Y*size, Z, fullRegion);

src/graphics/commons/Model.hpp

@@ -40,6 +40,14 @@ namespace model {
             const glm::vec3& norm,
             const UVRegion& region
         ); 
+        void addRect(
+            const glm::vec3& pos,
+            const glm::vec3& right,
+            const glm::vec3& up,
+            const glm::vec3& norm,
+            const UVRegion& uv,
+            const glm::mat4& transform
+        );
         void addTriangle(
             const glm::vec3& a,
             const glm::vec3& b,