Added scene related things

src/light_node.h

@@ -0,0 +1,42 @@
+#pragma once
+
+#include "scene_node.h"
+#include "texture.h"
+
+BEGIN_NAMESPACE
+
+// http://en.wikipedia.org/wiki/Shading#Lighting
+enum class light_type {
+    directional,
+    point,
+    spot
+};
+
+struct light_node : scene_node {
+    light_node(light_type type);
+
+    void calculate_local_transform() override;
+
+    light_type light_type_;
+
+    glm::vec4 ambient = glm::vec4(0.2, 0.2, 0.2, 1);
+    glm::vec4 diffuse = glm::vec4(0.5, 0.5, 0.5, 1);
+    glm::vec4 specular = glm::vec4(1);
+
+    glm::vec3 attenuation;
+
+    glm::vec3 spot_target;
+    float spot_cutoff;
+    float spot_exponent;
+
+    bool active = true;
+
+    int shadow_map_width = 1024;
+    glm::mat4 light_projection_matrix[6];
+    glm::mat4 world_to_light_matrix[6];
+    glm::mat4 shadow_map_bias_matrix;
+    glm::mat4 final_shadow_map_matrix[6];
+    std::shared_ptr<texture> shadow_map[6];
+};
+
+END_NAMESPACE