From e571743eb197289fcf7b4793a1aa2a0f037c8449 Mon Sep 17 00:00:00 2001
From: s473621 <marsau@st.amu.edu.pl>
Date: Wed, 7 Feb 2024 15:22:05 +0100
Subject: [PATCH] upd shader_tex

---
 .../cw 6/shaders/shader_5_1_tex.frag          | 88 ++++++++++++++++---
 1 file changed, 74 insertions(+), 14 deletions(-)

diff --git a/PlanetCreator/cw 6/shaders/shader_5_1_tex.frag b/PlanetCreator/cw 6/shaders/shader_5_1_tex.frag
index e51baab..b6b722d 100644
--- a/PlanetCreator/cw 6/shaders/shader_5_1_tex.frag	
+++ b/PlanetCreator/cw 6/shaders/shader_5_1_tex.frag	
@@ -1,23 +1,83 @@
 #version 430 core
 
-float AMBIENT = 0.1;
+uniform vec3 albedoColor; // Kolor podstawowy (albedo)
+uniform float metallic; // Wsp??czynnik metaliczno?ci
+uniform float roughness; // Wsp??czynnik chropowato?ci
 
-uniform vec3 color;
 uniform vec3 lightPos;
-uniform sampler2D colorTexture;
+uniform vec3 viewPos;
+
+in vec3 FragPos; // Pozycja fragmentu
+in vec3 Normal; // Normalna fragmentu
+out vec4 FragColor;
+
+// Obliczenie faktora odbicia ?wietlnego dla modelu PBR
+float DistributionGGX(vec3 N, vec3 H, float roughness);
+float GeometrySchlickGGX(float NdotV, float roughness);
+float GeometrySmith(vec3 N, vec3 V, vec3 L, float roughness);
 
-in vec3 vecNormal;
-in vec3 worldPos;
-in vec2 texCoord;
-out vec4 outColor;
-vec3 textureColorTemp;
 void main()
 {
-	vec3 lightDir = normalize(lightPos-worldPos);
-	vec3 normal = normalize(vecNormal);
-	float diffuse=max(0,dot(normal,lightDir));
+    vec3 N = normalize(Normal);
+    vec3 V = normalize(viewPos - FragPos); // Wektor widzenia
+    vec3 L = normalize(lightPos - FragPos); // Wektor do ?wiat?a
+    vec3 H = normalize(V + L); // Wektor po?owy
 
-	vec4 textureColor = texture2D(colorTexture,texCoord);
-	textureColorTemp=vec3(textureColor.r,textureColor.g,textureColor.b);
-	outColor = vec4(textureColorTemp*min(1,AMBIENT+diffuse), 1.0);
+    // Obliczenie faktora odbicia dla modelu PBR
+    float NDF = DistributionGGX(N, H, roughness);
+    float G = GeometrySmith(N, V, L, roughness);
+    vec3 F = vec3(0.04); // Aproksymacja Fresnel
+
+    // Obliczenie sk?adnika o?wietlenia dyfuzyjnego
+    vec3 kD = albedoColor.rgb / PI;
+
+    // Obliczenie sk?adnika o?wietlenia specularnego
+    vec3 kS = F * G * NDF / (4.0 * max(dot(N, V), 0.0) * max(dot(N, L), 0.0));
+    
+    // Obliczenie o?wietlenia bezpo?redniego
+    vec3 irradiance = vec3(1.0); // Przyk?adowe o?wietlenie otoczenia
+
+    // Model o?wietlenia oparty na PBR
+    vec3 diffuse = kD * irradiance;
+    vec3 specular = kS * irradiance;
+
+    vec3 color = diffuse + specular;
+    FragColor = vec4(color, 1.0);
+}
+
+// Funkcje do oblicze? PBR
+
+float DistributionGGX(vec3 N, vec3 H, float roughness)
+{
+    float a = roughness * roughness;
+    float a2 = a * a;
+    float NdotH = max(dot(N, H), 0.0);
+    float NdotH2 = NdotH * NdotH;
+
+    float num = a2;
+    float denom = (NdotH2 * (a2 - 1.0) + 1.0);
+    denom = PI * denom * denom;
+
+    return num / denom;
+}
+
+float GeometrySchlickGGX(float NdotV, float roughness)
+{
+    float r = (roughness + 1.0);
+    float k = (r * r) / 8.0;
+
+    float num = NdotV;
+    float denom = NdotV * (1.0 - k) + k;
+
+    return num / denom;
+}
+
+float GeometrySmith(vec3 N, vec3 V, vec3 L, float roughness)
+{
+    float NdotV = max(dot(N, V), 0.0);
+    float NdotL = max(dot(N, L), 0.0);
+    float ggx2 = GeometrySchlickGGX(NdotV, roughness);
+    float ggx1 = GeometrySchlickGGX(NdotL, roughness);
+
+    return ggx1 * ggx2;
 }