update shader version declaration for GL3

CGoGN/include/Utils/Shaders/shaderRadiancePerVertex.vert

 // ShaderRadiancePerVertex::vertexShaderText
 
-#extension GL_EXT_gpu_shader4 : enable // need GLSL v1.30 -> if not available, use a uniform for passing textureSize instead of calling textureSize2D
+//#extension GL_EXT_gpu_shader4 : enable // need GLSL v1.30 -> if not available, use a uniform for passing textureSize instead of calling textureSize2D
 
 ATTRIBUTE vec3 VertexPosition;
 ATTRIBUTE vec3 VertexNormal;
@@ -69,7 +69,7 @@ void set_eval_direction (vec3 v)
 
 void main ()
 {
-    int size = (textureSize2D(texture,0)).x; // supposed square matrix
+    int size = (textureSize(texture,0)).x; // supposed square matrix
 
     //init_K_tab();
     vec3 eyeV = normalize(camera - VertexPosition); // normalized outgoing line-of-sight vector

CGoGN/include/Utils/Shaders/shaderRadiancePerVertexInterp.frag

 // ShaderRadiancePerVertex::fragmentShaderInterpText
 
-#extension GL_EXT_gpu_shader4 : enable // need GLSL v1.30 -> if not available, use a uniform for passing textureSize instead of calling textureSize2D
+//#extension GL_EXT_gpu_shader4 : enable // need GLSL v1.30 -> if not available, use a uniform for passing textureSize instead of calling textureSize2D
 
 PRECISION;
 
@@ -75,7 +75,7 @@ void set_eval_direction (vec3 v)
 
 void main (void)
 {
-	int size = (textureSize2D(texture,0)).x; // supposed square matrix
+        int size = (textureSize(texture,0)).x; // supposed square matrix
 
 	vec3 eyeV = normalize(camera - vxPos); // normalized outgoing line-of-sight vector
 	eyeV = 2*dot(vxNorm,eyeV)*vxNorm-eyeV ; // symmetrize

CGoGN/src/Utils/GLSLShader.cpp

@@ -65,7 +65,7 @@ std::string GLSLShader::DEFINES_GL2=\
 
 
 std::string GLSLShader::DEFINES_GL3=\
-"#version 150\n"
+"#version 330\n"
 "#define PRECISION precision highp float\n"
 "#define ATTRIBUTE in\n"
 "#define VARYING_VERT out\n"