Added mesh

src/CMakeLists.txt

@@ -2,6 +2,7 @@ set(HEADERS
         ${HEADERS}
         ${CMAKE_CURRENT_SOURCE_DIR}/colour.h
         ${CMAKE_CURRENT_SOURCE_DIR}/fbo.h
+        ${CMAKE_CURRENT_SOURCE_DIR}/mesh.h
         ${CMAKE_CURRENT_SOURCE_DIR}/peripherals.h
         ${CMAKE_CURRENT_SOURCE_DIR}/peripherals_glfw.h
         ${CMAKE_CURRENT_SOURCE_DIR}/shader.h
@@ -9,9 +10,11 @@ set(HEADERS
         ${CMAKE_CURRENT_SOURCE_DIR}/texture_generator.h
         PARENT_SCOPE
         )
+
 set(SOURCE
         ${SOURCE}
         ${CMAKE_CURRENT_SOURCE_DIR}/fbo.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/mesh.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/peripherals_glfw.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/shader.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/texture.cpp

src/mesh.cpp

@@ -0,0 +1,148 @@
+#include "mesh.h"
+
+BEGIN_NAMESPACE
+
+constexpr char *BUFFER_OFFSET(int i) {
+    return (char *) NULL + i * sizeof(float);
+}
+
+constexpr int componentsInVertex() {
+    return 3 + 3 + 2; // position, normal, uv
+}
+
+constexpr int sizeOfVertexInBytes() {
+    return componentsInVertex() * sizeof(float);
+}
+
+mesh::mesh() {
+
+}
+
+mesh::~mesh() {
+    if (initialized) {
+        glDeleteVertexArrays(1, &vao_id);
+        glDeleteBuffers(1, &vbo_id);
+    }
+}
+
+void mesh::render(bool flat_shaded) {
+    if (!initialized) {
+        glGenVertexArrays(1, &vao_id);
+        glGenBuffers(1, &vbo_id);
+        initialized = true;
+    }
+
+    // construct data
+    if ((facets.size() * 3) > vbo_size_in_elements) {
+
+        if (vbo_data != nullptr)
+            delete[] vbo_data;
+
+        vbo_data = new float[componentsInVertex() * facets.size() * 3];
+        vbo_size_in_elements = facets.size() * 3;
+    }
+
+    // fill in buffer
+    int i = 0;
+    for (auto &f: facets) {
+        for (int j = 0; j < 3; j++) {
+            vbo_data[i++] = vertices[f.vertices[j]].position.x;
+            vbo_data[i++] = vertices[f.vertices[j]].position.y;
+            vbo_data[i++] = vertices[f.vertices[j]].position.z;
+            if (flat_shaded) {
+                vbo_data[i++] = f.normal.x;
+                vbo_data[i++] = f.normal.y;
+                vbo_data[i++] = f.normal.z;
+            } else {
+                vbo_data[i++] = vertices[f.vertices[j]].normal.x;
+                vbo_data[i++] = vertices[f.vertices[j]].normal.y;
+                vbo_data[i++] = vertices[f.vertices[j]].normal.z;
+            }
+            vbo_data[i++] = f.text_coords[j].x;
+            vbo_data[i++] = f.text_coords[j].y;
+        }
+    }
+
+    glBindVertexArray(vao_id);
+    glBindBuffer(GL_ARRAY_BUFFER, vbo_id);
+    glBufferData(GL_ARRAY_BUFFER, sizeOfVertexInBytes() * facets.size() * 3, vbo_data, GL_DYNAMIC_DRAW);
+
+    glEnableVertexAttribArray(0); // vertices on stream 0
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeOfVertexInBytes(), BUFFER_OFFSET(0));
+
+    glEnableVertexAttribArray(1); // normals on stream 1
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, sizeOfVertexInBytes(), BUFFER_OFFSET(3));
+
+    glEnableVertexAttribArray(2); // text coords on stream 2
+    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, sizeOfVertexInBytes(), BUFFER_OFFSET(6));
+
+    glDrawArrays(GL_TRIANGLES, 0, facets.size() * 3);
+
+    glDisableVertexAttribArray(2);
+    glDisableVertexAttribArray(1);
+    glDisableVertexAttribArray(0);
+
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+    glBindVertexArray(0);
+}
+
+void mesh::merge(mesh &mesh) {
+    vertices.reserve(vertices.size() + mesh.vertices.size());
+    vertices.insert(vertices.end(), mesh.vertices.begin(), mesh.vertices.end());
+
+    auto original_facet_count = facets.size();
+    facets.reserve(facets.size() + mesh.facets.size());
+    for (auto &f: mesh.facets) {
+        facet new_f = f;
+        new_f.a += original_facet_count;
+        new_f.b += original_facet_count;
+        new_f.c += original_facet_count;
+        facets.push_back(new_f);
+    }
+
+    size_t original_edge_count = edges.size();
+    edges.reserve(edges.size() + mesh.edges.size());
+    for (auto &e: mesh.edges) {
+        edge new_edge = e;
+        new_edge.from += original_edge_count;
+        new_edge.to += original_edge_count;
+        edges.push_back(new_edge);
+    }
+}
+
+void mesh::copy(mesh &mesh) {
+    vertices = mesh.vertices;
+    facets = mesh.facets;
+    edges = mesh.edges;
+}
+
+void calculate_normals(mesh &mesh) {
+    for (auto &vertex: mesh.vertices)
+        vertex.normal = glm::vec3(0);
+
+    for (auto &facet: mesh.facets) {
+        glm::vec3 a = mesh.vertices[facet.b].position - mesh.vertices[facet.a].position;
+        glm::vec3 b = mesh.vertices[facet.c].position - mesh.vertices[facet.a].position;
+        facet.normal = cross(a, b);
+        if (length(facet.normal) > 0.00001) {
+            facet.normal = normalize(facet.normal);
+        }
+
+        mesh.vertices[facet.a].normal += facet.normal;
+        mesh.vertices[facet.b].normal += facet.normal;
+        mesh.vertices[facet.c].normal += facet.normal;
+    }
+
+    for (auto &vertex: mesh.vertices)
+        vertex.normal = normalize(vertex.normal);
+}
+
+void flip_normals(mesh &mesh) {
+    for (auto &vertex: mesh.vertices)
+        vertex.normal = -vertex.normal;
+
+    for (auto &facet: mesh.facets)
+        facet.normal = -facet.normal;
+}
+
+END_NAMESPACE

src/mesh.h

@@ -0,0 +1,52 @@
+#pragma once
+
+#include "defines.h"
+#include "glm/glm.hpp"
+#include <vector>
+
+BEGIN_NAMESPACE
+
+struct vertex {
+    glm::vec3 position;
+    glm::vec3 normal;
+};
+
+struct facet {
+    union {
+        struct {
+            size_t a, b, c;
+        };
+        size_t vertices[3];
+    };
+    glm::vec3 normal;
+    glm::vec2 text_coords[3];
+};
+
+struct edge {
+    size_t from;
+    size_t to;
+};
+
+struct mesh {
+    mesh();
+    ~mesh();
+
+    std::vector<vertex> vertices;
+    std::vector<facet> facets;
+    std::vector<edge> edges;
+
+    void render(bool flat_shaded);
+    void merge(mesh &mesh);
+    void copy(mesh &mesh);
+
+    bool initialized = false;
+    GLuint vbo_id = 0;
+    GLuint vao_id = 0;
+    float *vbo_data = nullptr;
+    int vbo_size_in_elements = 0;
+};
+
+void calculate_normals(mesh & mesh);
+void flip_normals(mesh & mesh);
+
+END_NAMESPACE

src/shader.cpp

@@ -1,7 +1,5 @@
 #include "shader.h"
-#include <string>
 #include <iostream>
-#include <vector>
 
 BEGIN_NAMESPACE
 
@@ -68,10 +66,10 @@ void shader::unuse() const {
 }
 
 int shader::getUniform(const char *uniformName) {
-    if (uniformCache.count(uniformName) == 0) {
-        uniformCache[uniformName] = glGetUniformLocation(program_id, uniformName);
+    if (uniform_cache.count(uniformName) == 0) {
+        uniform_cache[uniformName] = glGetUniformLocation(program_id, uniformName);
     }
-    return uniformCache[uniformName];
+    return uniform_cache[uniformName];
 }
 
 void shader::setMatrix3Uniform(float *matrix, const char *uniformName) {

src/shader.h

@@ -7,7 +7,6 @@ BEGIN_NAMESPACE
 
 class shader {
 public:
-
     shader(const char *vs_content, const char *ps_content);
     virtual ~shader();
 
@@ -27,7 +26,7 @@ public:
 private:
     GLuint program_id;
     GLuint shader_ids[2];
-    std::map<const char *, int> uniformCache;
+    std::map<const char *, int> uniform_cache;
 };