feat(render): Renderer with LOD selection, 3.3 and 4.3+ upload paths, headless smoke test

src/gl/handle.cpp

@@ -109,6 +109,25 @@ void Buffer::upload_sub(const void* data, usize bytes, usize offset) const noexc
                   data);
 }
 
+void Buffer::storage(usize bytes, GLbitfield flags) const noexcept {
+  if (glBufferStorage == nullptr) {
+    return;  // not resolved on this driver: the caller checked caps() first
+  }
+  bind();
+  glBufferStorage(GL_ARRAY_BUFFER, static_cast<GLsizeiptr>(bytes), nullptr, flags);
+}
+
+void* Buffer::map_range(usize offset, usize bytes, GLbitfield access) const noexcept {
+  bind();
+  return glMapBufferRange(GL_ARRAY_BUFFER, static_cast<GLintptr>(offset),
+                          static_cast<GLsizeiptr>(bytes), access);
+}
+
+bool Buffer::unmap() const noexcept {
+  bind();
+  return glUnmapBuffer(GL_ARRAY_BUFFER) == GL_TRUE;
+}
+
 void Buffer::destroy(GLuint id) noexcept { glDeleteBuffers(1, &id); }
 
 // -------------------------------------------------------------- VertexArray