Initial commit

1 files changed, 56 insertions, 0 deletions

diff --git a/09-september/resources/shaders/shader.frag b/09-september/resources/shaders/shader.frag
new file mode 100644
index 0000000..44e579c
--- /dev/null
+++ b/09-september/resources/shaders/shader.frag
@@ -0,0 +1,56 @@
+#version 420
+
+in vec2 Fragment_UV;
+in vec4 Fragment_Color;
+in vec3 toLightVector[4];
+in vec3 toEyeVector;
+
+layout(location = 0) out vec4 out_color;
+
+uniform vec4 lightColor[4];
+uniform vec3 attenuation[4];
+uniform sampler2D Texture;
+uniform sampler2D normalMap;
+
+void main()
+{
+    vec4 totalDiffuse = vec4(0.0, 0.0, 0.0, 1.0);
+    vec4 totalSpecular = vec4(0.0, 0.0, 0.0, 1.0);
+
+    /* We get the normal from the normal map and we transform it into world space */
+    vec3 normal = normalize( (255.0 / 128.0 * texture(normalMap, Fragment_UV) - 1.0).xyz );
+
+    for(int i = 0; i < 4; i++)
+    {
+        /*Light Attenuation*/
+        float dist = length(toLightVector[i]);
+        float attFactor = attenuation[i].x + (attenuation[i].y * dist) + (attenuation[i].z * dist * dist);
+        vec3 unitToLightVector = normalize(toLightVector[i]);
+
+        /*Diffuse lighting*/
+
+        /*La intensidad es el cos entre la normal y el vector hacia la luz*/
+        float brightness = dot(unitToLightVector, normalize(normal));
+        /*No queremos luz negativa ni mayor a 1*/
+        brightness = max(brightness, 0.0);
+        totalDiffuse = totalDiffuse + (brightness * lightColor[i]) / attFactor;
+
+        /* Specular lighting */
+
+        /* Reflejamos el vector hacia la luz (su inverso) en la normal */
+        vec3 Vector_ReflectedLight = reflect(-unitToLightVector, normal);
+
+        /* La luz especular es el cos del angulo entre el vector hacia el ojo y la luz reflectada en la normal */
+        float specularity = clamp( dot(Vector_ReflectedLight, toEyeVector), 0, 1 );
+        float reflectivity = 0.5;
+        /* Que tan grande es el specular highlight */
+        specularity = pow(specularity, 10);
+        totalSpecular = totalSpecular + clamp( reflectivity * specularity * lightColor[i], 0, 1)  / attFactor;
+    }
+
+    /* Ambient Light */
+    totalDiffuse = max(totalDiffuse, 0.2);
+
+    /* Juntamos todo para el color final*/
+    out_color = totalDiffuse * texture(Texture, Fragment_UV) + totalSpecular;
+}