1 files changed, 38 insertions, 0 deletions
diff --git a/src/scene.cpp b/src/scene.cpp
index e69de29..44e7028 100644
--- a/src/scene.cpp
+++ b/src/scene.cpp
@@ -0,0 +1,38 @@
+#include "scene.hpp"
+
+Scene::Scene() {
+  directional_light = {0, 0, -1};
+  viewport_dimension = {3, 2};
+  scene_dimension = {SCREEN_WIDTH / 2, SCREEN_HEIGHT};
+
+  z_plane = int2fx(1);
+}
+
+POINT Scene::project_2d(VECTOR vertex) {
+  POINT pt = {0, 0};
+
+  if (vertex.z != 0) {
+    pt.x = fxdiv(z_plane, vertex.z);
+    pt.y = fxmul(vertex.y, pt.x);
+    pt.x = fxmul(vertex.x, pt.x);
+  }
+
+  return pt;
+}
+
+POINT Scene::viewport_to_scene(POINT p) {
+  FIXED x = fxmul(p.x, int2fx(std::get<0>(scene_dimension) /
+                              std::get<0>(viewport_dimension)));
+  FIXED y = fxmul(p.y, int2fx(std::get<1>(scene_dimension) /
+                              std::get<1>(viewport_dimension)));
+  return {x >> FIX_SHIFT, y >> FIX_SHIFT};
+}
+
+void Scene::draw_line(POINT p0, POINT p1, std::uint8_t pal_idx) {
+  POINT scene_p0 = viewport_to_scene(p0);
+  POINT scene_p1 = viewport_to_scene(p1);
+
+  std::uint16_t pixels = (pal_idx << 8) | pal_idx;
+  bmp16_line(scene_p0.x, scene_p0.y, scene_p1.x, scene_p1.y, pixels, vid_page,
+             SCREEN_WIDTH);
+}