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

resources/fragmentShader_pulse.glsl

@@ -0,0 +1,81 @@
+#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 fragBoundPos;
+in vec3 fragBaryc;
+/* does gles2 already includes it and considers it a redeclaration
+in vec4 gl_FragCoord;
+*/
+
+in mat3 TBN;
+
+uniform vec3 lightCol;
+uniform vec3 lightPos;
+uniform vec3 eyePos;
+uniform float time;
+
+
+//uniform vec3 diffuseColor;
+uniform sampler2D colorMap;   //campionatore 2d 
+uniform sampler2D normalMap;   //campionatore 2d 
+
+out vec4 FragColor;
+/*
+int nScanLines = 16;
+*/
+float f_nScanLines = 16.0;
+
+float PI = 3.14159265358979323846264338327950288;
+
+
+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));
+    float attenuation = 1.0f / (0.01 * lightDistance);
+        
+    float diffuseFactor = max(dot(aLuceDir, fragNormal), 0.0);
+        
+    float specularFactor = pow(max(dot(rimbalzoDir, allOcchioDir), 0.0), 100.0f);
+        
+    return attenuation * ( specularFactor + diffuseFactor);  
+}
+
+void main()
+{   
+
+    vec4 texColor = texture(colorMap,frag_uv);
+    vec3 normalPix = texture(normalMap,frag_uv).rgb;
+    normalPix = normalPix * 2.0 - 1.0;   
+    normalPix = normalize(TBN * normalPix); 
+
+    float sinExp = 500.0 * (0.05 + 0.95 * sin( 3.14159265359 * 0.25 * (time * time)));
+    //float sinExp = 500.0;
+    float clampBound = 0.25;
+
+    vec3 result = 0.7 * vec3(1,0.5,1);
+    float locy = fragBoundPos.y;
+    locy = mod(locy, 1.0f / f_nScanLines);
+    float dist = abs(pow(locy - (time / f_nScanLines), 0.1));
+    float glowFac = (1.0 / clampBound) * abs(clamp(
+                    pow(sin(dist * PI), sinExp), -clampBound, clampBound));
+
+    float scrDist = sin( PI * ( 1.0 - clamp(pow(gl_FragCoord.z , 100.0), 0.0, 1.0)));
+    result *= scrDist;
+    FragColor = vec4(result, 1.0f);
+    FragColor*=glowFac;
+    //FragColor = vec4(abs(fragNormal.x) * glowFac ,abs(fragNormal.y) * glowFac , abs(fragNormal.z) * glowFac , 1.0f * scrDist);
+    
+	float baryThreshold = 0.05f;
+	if(fragBaryc.x > baryThreshold && fragBaryc.y > baryThreshold && fragBaryc.z > baryThreshold) {
+        FragColor = vec4(0.05 * FragColor.xyz, 0);
+    }
+}