initial commit

1 files changed, 96 insertions, 0 deletions

diff --git a/src/client/render/camera.cc b/src/client/render/camera.cc
new file mode 100644
index 0000000..1ea4dfb
--- /dev/null
+++ b/src/client/render/camera.cc
@@ -0,0 +1,96 @@
+#include "client/render/camera.hh"
+
+namespace client {
+namespace render {
+namespace camera {
+
+float& get_xfov() noexcept {
+    static float xfov = 100.0f;
+    return xfov;
+}
+
+glm::vec3& get_pos() noexcept {
+    static glm::vec3 pos{0.0f, 0.0f, 0.0f};
+    return pos;
+}
+
+glm::vec3& get_front() noexcept {
+    static glm::vec3 front{0.0f, 0.0f, 0.0f};
+    return front;
+}
+
+glm::vec3& get_up() noexcept {
+    static glm::vec3 front{0.0f, 1.0f, 0.0f};
+    return front;
+}
+
+static glm::mat4 make_view() noexcept {
+    const glm::vec3& pos = get_pos();
+    return glm::lookAt(pos, pos + get_front(), get_up());
+}
+
+glm::mat4& get_view() noexcept {
+    static glm::mat4 view = make_view();
+    return view;
+}
+
+static glm::mat4 make_proj() noexcept {
+    const glm::vec2& window = client::render::get_window_size();
+    return glm::perspective(glm::radians(get_yfov()), window.x / window.y,
+                            get_znear(), get_zfar());
+}
+
+glm::mat4& get_proj() noexcept {
+    static glm::mat4 proj = make_proj();
+    return proj;
+}
+
+static frustum make_frustum() noexcept {
+    const glm::mat4 matrix = get_proj() * get_view();
+    const glm::vec4 row_x = glm::row(matrix, 0);
+    const glm::vec4 row_y = glm::row(matrix, 1);
+    const glm::vec4 row_z = glm::row(matrix, 2);
+    const glm::vec4 row_w = glm::row(matrix, 3);
+
+    frustum ret{row_w + row_x, row_w - row_x, row_w + row_y,
+                row_w - row_y, row_w + row_z, row_w - row_z};
+    std::ranges::transform(ret, std::begin(ret), [](const auto& matrix) {
+        return glm::normalize(matrix);
+    });
+    return ret;
+}
+
+frustum& get_frustum() noexcept {
+    static frustum ret = make_frustum();
+    return ret;
+}
+
+float& get_znear() noexcept {
+    static float znear = 0.1f;
+    return znear;
+}
+
+float& get_zfar() noexcept {
+    static float zfar = 1024.0f;
+    return zfar;
+}
+
+float get_yfov() noexcept {
+    const glm::vec2& window = client::render::get_window_size();
+    const float yfov =
+        2.0f * std::atan((window.y / window.x) *
+                         std::tan(glm::radians(get_xfov()) / 2.0f));
+    return glm::degrees(yfov);
+}
+
+void update() noexcept {
+    get_view() = make_view(); // specific order here!
+    get_proj() = make_proj();
+    get_frustum() = make_frustum();
+}
+
+} // namespace camera
+
+} // namespace render
+
+} // namespace client