add 'u_lightDir' to main shader

src/graphics/render/Skybox.cpp

@@ -180,10 +180,11 @@ void Skybox::refresh(const DrawContext& pctx, float t, float mie, uint quality)
     };
     t *= M_PI*2.0f;
     
+    lightDir = glm::normalize(glm::vec3(sin(t), -cos(t), 0.0f));
     shader->uniform1i("u_quality", quality);
     shader->uniform1f("u_mie", mie);
     shader->uniform1f("u_fog", mie - 1.0f);
-    shader->uniform3f("u_lightDir", glm::normalize(glm::vec3(sin(t), -cos(t), 0.0f)));
+    shader->uniform3f("u_lightDir", lightDir);
     for (uint face = 0; face < 6; face++) {
         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_CUBE_MAP_POSITIVE_X + face, cubemap->getId(), 0);
         shader->uniform3f("u_xaxis", xaxs[face]);

src/graphics/render/Skybox.hpp

@@ -3,6 +3,7 @@
 #include <memory>
 #include <string>
 #include <vector>
+#include <glm/glm.hpp>
 #include "typedefs.hpp"
 #include "maths/fastmaths.hpp"
 
@@ -27,6 +28,7 @@ class Skybox {
     Shader* shader;
     bool ready = false;
     FastRandom random;
+    glm::vec3 lightDir;
 
     std::unique_ptr<Mesh> mesh;
     std::unique_ptr<Batch3D> batch3d;
@@ -52,4 +54,8 @@ public:
     bool isReady() const {
         return ready;
     }
+
+    const glm::vec3 getLightDir() const {
+        return lightDir;
+    }
 };

src/graphics/render/WorldRenderer.cpp

@@ -166,6 +166,7 @@ void WorldRenderer::setupWorldShader(
     shader->uniform1f("u_fogFactor", fogFactor);
     shader->uniform1f("u_fogCurve", settings.graphics.fogCurve.get());
     shader->uniform1f("u_dayTime", level->getWorld()->getInfo().daytime);
+    shader->uniform2f("u_lightDir", skybox->getLightDir());
     shader->uniform3f("u_cameraPos", camera.position);
     shader->uniform1i("u_cubemap", 1);