feat: add lights

src/light.cpp

@@ -0,0 +1,56 @@
+#include "light.h"
+
+#include "../lib/glm/gtc/matrix_transform.hpp"
+
+#include "shader.h"
+#include "state.h"
+
+Light::Light()
+    : Entity()
+    , type_(Type::DIRECTIONAL)
+    , color_(1.0f, 1.0f, 1.0f)
+    , intensity_(1.0f)
+    , linear_attenuation_(0.0f)
+{
+}
+
+void Light::prepare(int index, std::shared_ptr<Shader>& shader) const
+{
+	if (!shader)
+		return;
+
+	// Build uniform names for this light index
+	std::string light_vector =
+	    "lights[" + std::to_string(index) + "].vector";
+	std::string light_color = "lights[" + std::to_string(index) + "].color";
+	std::string light_intensity =
+	    "lights[" + std::to_string(index) + "].intensity";
+	std::string light_linear_att =
+	    "lights[" + std::to_string(index) + "].linear_att";
+
+	// Get uniform locations
+	int vector_loc	   = shader->uniform_location(light_vector.c_str());
+	int color_loc	   = shader->uniform_location(light_color.c_str());
+	int intensity_loc  = shader->uniform_location(light_intensity.c_str());
+	int linear_att_loc = shader->uniform_location(light_linear_att.c_str());
+
+	// Calculate light vector in view space
+	glm::vec4 light_vector_view;
+	if (type_ == Type::DIRECTIONAL) {
+		// For directional lights, w = 0
+		glm::vec3 direction =
+		    glm::normalize(position_); // Use position as direction
+		light_vector_view =
+		    state::view_matrix * glm::vec4(direction, 0.0f);
+	} else {
+		// For point lights, w = 1
+		light_vector_view =
+		    state::view_matrix * glm::vec4(position_, 1.0f);
+	}
+
+	// Set uniforms
+	Shader::set_vec4(vector_loc, light_vector_view);
+	Shader::set_vec3(color_loc, color_);
+	Shader::set_float(intensity_loc, intensity_);
+	Shader::set_float(linear_att_loc, linear_attenuation_);
+}