Add deprecation notice

Author: Thomas Harrison

README.md

@@ -25,6 +25,15 @@ make build CONFIG=Release
 make install CONFIG=Release
 ```
 
+## Deprecation Notice
+
+The following have been deprecated and will be removed or replaced in a future
+release.
+
+| What will be removed      | Why                                                 |
+| ------------------------- | --------------------------------------------------- |
+| `Shader::defaultShader()` | This shader will always outlive the OpenGL context. |
+
 ## CMake Options
 
 | Option              | Description                   | Default |

include/glpp/Shader.hpp

@@ -187,6 +187,10 @@ namespace glpp {
          *
          * This shader takes a Vertex from VBO.hpp,
          *
+         * @deprecated A default shader will be provided in a different form, if
+         * at all, in future releases. This shader will always outlive the
+         * OpenGL context.
+         *
          * Uniforms:
          * - mvp: mat4
          * - model: mat4

src/Shader.cpp

@@ -249,6 +249,7 @@ void main() {
     FragColor = texture(gTexture, FragTex);
 })";
 
+    [[deprecated("A default shader will be provided in a different form, if at all, in future releases")]]
     Shader & Shader::defaultShader() {
         static Shader shader(defaultVertexShaderSource,
                              defaultFragmentShaderSource);