ported the University CGI demo from WINDOWS + GLUT + GLEW + GLU + OpenGL 4 to LINUX WAYLAND + EGL + GLES 2 with minimal cuts

resources/fragmentShader_gourard.glsl

@@ -0,0 +1,60 @@
+#version 300 es
+
+/*this will affect all the float guys (float, vecN, matN )*/
+precision mediump float;
+
+in vec3 fragPos;  //vertice in coordinata del mondo
+in vec3 fragNormal;
+in vec2 frag_uv;  //coordinate 2d di texure
+in vec3 fragBaryc;
+
+in vec3 T;
+in vec3 B;
+in vec3 N;
+
+uniform vec3 lightCol;
+uniform vec3 lightPos;
+uniform vec3 eyePos;
+
+//uniform vec3 diffuseColor;
+uniform sampler2D colorMap;   //campionatore 2d 
+uniform sampler2D normalMap;   //campionatore 2d 
+
+out vec4 FragColor;  
+
+
+float illuminazione(vec3 lucePos, vec3 fragPos, vec3 eyePos, vec3 fragNormal){
+    fragNormal = normalize(fragNormal);
+       
+    vec3 aLuceDir = normalize(lucePos - fragPos);
+    vec3 allOcchioDir = normalize(eyePos - fragPos);
+    float lightDistance = length(lucePos - fragPos);
+    vec3 rimbalzoDir = normalize(reflect(-aLuceDir,fragNormal));
+	rimbalzoDir = reflect(-aLuceDir,fragNormal);
+    float attenuation = 1.0f / (0.01 * lightDistance);
+        
+    float diffuseFactor = max(dot(aLuceDir, fragNormal), 0.0);
+        
+    float specularFactor = pow(max(dot(rimbalzoDir, allOcchioDir), 0.0), 500.0f);
+        
+    return attenuation * ( specularFactor + diffuseFactor );  
+	//return attenuation * diffuseFactor;
+}
+
+void main()
+{   
+    vec3 Nor = normalize(N);
+    vec3 Tan = normalize(T);
+    vec3 Bit = normalize(B);
+	mat3 TBN = mat3(Tan,Bit,Nor);
+    vec4 texColor = texture(colorMap,frag_uv);
+    vec3 normalPix = texture(normalMap,frag_uv).rgb;
+    normalPix = normalPix * 2.0 - 1.0;
+    normalPix = normalize(TBN * normalPix);
+	normalPix = normalize(TBN * vec3(0,0,1));
+	
+    vec3 result = texColor.rgb * illuminazione(lightPos, fragPos, eyePos, normalPix);
+	//FragColor = vec4(normalPix, 1.0f);
+    FragColor = vec4(texColor.xyz * illuminazione(lightPos, fragPos, eyePos, fragNormal), 1.0f);
+
+}