destroy program in shader destructor

src/render/Shader.cpp

@@ -10,4 +10,11 @@ GLint CShader::getUniformLocation(const std::string& unif) {
     }
 
     return itpos->second;
+}
+
+CShader::~CShader() {
+    // destroy shader
+    if (program != 0) {
+        glDeleteProgram(program);
+    }
 }

src/render/Shader.hpp

@@ -5,7 +5,9 @@
 
 class CShader {
 public:
-    GLuint program;
+    ~CShader();
+
+    GLuint program = 0;
     GLint proj;
     GLint color;
     GLint tex;