refactor into files

src/main/cpp/shader.h

@@ -0,0 +1,16 @@
+#pragma once
+#include <glad/gles2.h>
+#include <string>
+
+class Shader
+{
+    GLuint m_program = 0;
+public:
+    void destroy();
+    bool load(const std::string& vertexFilename, const std::string& fragmentFilename);
+    void use() const;
+    GLint getUniformLocation(const char* name) const;
+    GLint getAttribLocation(const char* name) const;
+private:
+    GLuint compile(GLenum type, const char* source);
+};