add particles lighting

src/graphics/render/ParticlesRenderer.cpp

@@ -8,16 +8,20 @@
 #include "window/Camera.hpp"
 #include "world/Level.hpp"
 #include "voxels/Chunks.hpp"
+#include "settings.hpp"
 
 size_t ParticlesRenderer::visibleParticles = 0;
 size_t ParticlesRenderer::aliveEmitters = 0;
 
-ParticlesRenderer::ParticlesRenderer(const Assets& assets, const Level& level)
-    : batch(std::make_unique<MainBatch>(1024)), level(level) {
-
-    auto region = util::get_texture_region(assets, "blocks:bazalt", "");
-    emitters.push_back(std::make_unique<Emitter>(glm::vec3(0, 100, 0), Particle {
-        nullptr, glm::vec3(), glm::vec3(), 5.0f, region.region
+ParticlesRenderer::ParticlesRenderer(
+    const Assets& assets, const Level& level, const GraphicsSettings* settings
+)
+    : batch(std::make_unique<MainBatch>(1024)),
+      level(level),
+      settings(settings) {
+    auto region = util::get_texture_region(assets, "blocks:grass_top", "");
+    emitters.push_back(std::make_unique<Emitter>(glm::vec3(0, 80, 0), Particle {
+        nullptr, 0, glm::vec3(), glm::vec3(), 5.0f, region.region
     },region.texture, 0.002f, -1));
 }
 
@@ -42,6 +46,9 @@ void ParticlesRenderer::renderParticles(const Camera& camera, float delta) {
     const auto& right = camera.right;
     const auto& up = camera.up;
 
+    const auto& chunks = *level.chunks;
+    bool backlight = settings->backlight.get();
+
     std::vector<const Texture*> unusedTextures;
 
     for (auto& [texture, vec] : particles) {
@@ -57,14 +64,21 @@ void ParticlesRenderer::renderParticles(const Camera& camera, float delta) {
         while (iter != vec.end()) {
             auto& particle = *iter;
 
-            update_particle(particle, delta, *level.chunks);
+            update_particle(particle, delta, chunks);
 
+            glm::vec4 light(1, 1, 1, 0);
+            if (particle.emitter->behaviour.lighting) {
+                light = MainBatch::sampleLight(
+                    particle.position, chunks, backlight
+                );
+                light *= 0.7f + (particle.random % 300) * 0.001f;
+            }
             batch->quad(
                 particle.position,
                 right,
                 up,
                 glm::vec2(0.3f),
-                glm::vec4(1),
+                light,
                 glm::vec3(1.0f),
                 particle.region
             );