2 files changed, 12 insertions, 2 deletions
diff --git a/assets/shaders/fragment.glsl b/assets/shaders/fragment.glsl
index f8e9e46..eca50d9 100644
--- a/assets/shaders/fragment.glsl
+++ b/assets/shaders/fragment.glsl
@@ -1,11 +1,17 @@
 #version 330 core
 
 uniform sampler2D tex;
+uniform vec3 sun_direction;
 
+in vec3 surface_normal;
 in vec2 frag_tex_coord;
 
 out vec4 color;
 
 void main() {
-    color = texture(tex, frag_tex_coord);
+    float brightness = dot(normalize(surface_normal), normalize(-sun_direction));
+    vec3 diffuse = vec3(max(brightness, 0.3));
+
+    color = vec4(diffuse, 1.0) * texture(tex, frag_tex_coord);
+    // color = texture(tex, frag_tex_coord);
 }
 \ No newline at end of file
diff --git a/assets/shaders/vertex.glsl b/assets/shaders/vertex.glsl
index 1ad43f4..c59d6cd 100644
--- a/assets/shaders/vertex.glsl
+++ b/assets/shaders/vertex.glsl
@@ -5,11 +5,15 @@ uniform mat4 view_matrix;
 uniform mat4 projection_matrix;
 
 layout (location = 0) in vec3 position;
-layout (location = 1) in vec2 tex_coord;
+layout (location = 1) in vec3 normal;
+layout (location = 2) in vec2 tex_coord;
 
 out vec2 frag_tex_coord;
+out vec3 surface_normal;
 
 void main() {
     gl_Position = projection_matrix * view_matrix * model_matrix * vec4(position, 1.0);
     frag_tex_coord = tex_coord;
+
+    surface_normal = (model_matrix * vec4(normal, 0.0)).xyz;
 }
 \ No newline at end of file