Initial commit

src/mesh.cpp

@@ -0,0 +1,86 @@
+#include <cstddef>
+#include <utility>
+
+#include "mesh.hpp"
+
+namespace Fan
+{
+
+Rc<Mesh> Mesh::create(const std::vector<Vertex>& vertices,
+                      const std::vector<GLuint>& indices/* = {}*/)
+{
+    GLuint VBO{}, VAO{}, EBO{};
+    bool has_indices = !indices.empty();
+
+    glGenBuffers(1, &VBO);
+    glGenVertexArrays(1, &VAO);
+    glBindVertexArray(VAO);
+
+    // Upload vertex data
+    glBindBuffer(GL_ARRAY_BUFFER, VBO);
+    glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(vertices[0]),
+                 &vertices[0], GL_STATIC_DRAW);
+
+    // Upload index data
+    if (has_indices) {
+        glGenBuffers(1, &EBO);
+        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
+        glBufferData(GL_ELEMENT_ARRAY_BUFFER, indices.size() * sizeof(indices[0]),
+                     &indices[0], GL_STATIC_DRAW);
+    }
+
+    // Define vertex data layout
+    GLsizei stride = sizeof(Vertex);
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, stride, (void*)offsetof(Vertex, position));
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, stride, (void*)offsetof(Vertex, normal));
+    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, stride, (void*)offsetof(Vertex, texture_coords));
+    glEnableVertexAttribArray(0);
+    glEnableVertexAttribArray(1);
+    glEnableVertexAttribArray(2);
+
+    return make_rc<Mesh>(vertices, indices, has_indices, VBO, VAO, EBO);
+}
+
+Mesh::~Mesh()
+{
+    glDeleteBuffers(1, &m_EBO);
+    glDeleteBuffers(1, &m_VBO);
+    glDeleteVertexArrays(1, &m_VAO);
+}
+
+Mesh::Mesh(Mesh&& other) noexcept
+    : m_vertices(std::move(other.m_vertices))
+    , m_indices(std::move(other.m_indices))
+    , m_has_indices(std::exchange(other.m_has_indices, false))
+    , m_VBO(std::exchange(other.m_VBO, 0))
+    , m_VAO(std::exchange(other.m_VAO, 0))
+    , m_EBO(std::exchange(other.m_EBO, 0))
+{
+}
+
+Mesh& Mesh::operator=(Mesh&& other) noexcept
+{
+    if (this == &other) { return *this; }
+
+    std::swap(m_vertices, other.m_vertices);
+    std::swap(m_indices, other.m_indices);
+    std::swap(m_has_indices, other.m_has_indices);
+    std::swap(m_VBO, other.m_VBO);
+    std::swap(m_VAO, other.m_VAO);
+    std::swap(m_EBO, other.m_EBO);
+
+    return *this;
+}
+
+void Mesh::draw() const
+{
+    glBindVertexArray(m_VAO);
+
+    if (m_has_indices) {
+        glDrawElements(GL_TRIANGLES, m_indices.size(), GL_UNSIGNED_INT, 0);
+    } else {
+        glDrawArrays(GL_TRIANGLES, 0, m_vertices.size());
+    }
+}
+
+} // namespace Fan