Skia, in contrast, is a portability engine. The same Skia code compiles and runs on Windows (using Direct3D or OpenGL), macOS/iOS (using Metal), Linux (Vulkan/OpenGL), Android (Vulkan/OpenGL), and even in web browsers via WebAssembly with WebGL. Skia’s backend abstraction means the developer never touches a platform-specific API. For cross-platform applications like Chrome, Flutter, or Figma’s desktop client, this is invaluable.
Rendering high-quality text and smooth vector paths is notoriously difficult in raw OpenGL. One must load fonts, rasterize glyphs into textures, manage a glyph atlas, handle kerning and subpixel positioning, and write shaders for gamma correction and hinting. Similarly, drawing a Bezier path requires tessellating it into triangles (using libraries like libtess2) or implementing GPU-side path rendering (using NV_path_rendering, which is not standard OpenGL). This is weeks or months of engineering work. opengl default vs skia
OpenGL runs on virtually every desktop and mobile platform (Windows, macOS via legacy compatibility, Linux, Android, iOS). However, it is a deprecated API on macOS (replaced by Metal) and has been superseded by Vulkan on many high-performance systems. Maintaining an OpenGL backend across platforms increasingly requires fallbacks to Angle (OpenGL on top of DirectX) or other compatibility layers. Skia, in contrast, is a portability engine
One of the most notorious challenges of default OpenGL is its stateful nature. Setting a texture, shader, or blend mode has global side effects. A well-structured OpenGL application must meticulously save and restore state, sort draw calls by material to minimize pipeline changes, and manually implement batching. A naive OpenGL implementation drawing hundreds of distinct UI elements (buttons, text, icons) would issue hundreds of draw calls, each potentially switching shaders and textures, leading to severe CPU overhead and driver stalls. Similarly, drawing a Bezier path requires tessellating it