Porting WBE to Recent Software Releases

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The code in this book was developed for and tested on particular versions of the libraries it depends on, including Python 3.12, Skia 87, Tk 8.6.14, DukPy 0.3.0, and PySDL2 0.9.15. This page documents code changes necessary to port the code of Web Browser Engineering to the most recent release of each library. It will be regularly updated as new versions are released and tested.

Porting to Skia 124

The text of this book uses Skia 87, and the associated skia-python 87.6 release. Skia 124, and the associated skia-python 124b7 release, changes a couple of APIs used in this book. One major change is the removal of FilterQuality, used in Chapter 15, and its replacement by SamplingOptions. This requires updating parse_image_rendering like so:

def parse_image_rendering(quality):
    if quality == "high-quality":
        return skia.SamplingOptions(skia.CubicResampler.Mitchell())
    elif quality == "crisp-edges":
        return skia.SamplingOptions(
            skia.FilterMode.kNearest, skia.MipmapMode.kNone)
        return skia.SamplingOptions(
            skia.FilterMode.kLinear, skia.MipmapMode.kLinear)

And changing the execute method of DrawImage like so:

class DrawImage:
    def execute(self, canvas):
        canvas.drawImageRect(self.image, self.rect, self.quality)

The new API is somewhat cleaner and more customizable.

Finally, add these SDL_GL_SetAttribute calls to set GL version Skia expects:

class Browser:
    def __init__(self):
        self.sdl_window = sdl2.SDL_CreateWindow(b'Browser',
            WIDTH, HEIGHT,
            sdl2.SDL_WINDOW_SHOWN | sdl2.SDL_WINDOW_OPENGL)

        sdl2.SDL_GL_SetAttribute(sdl2.SDL_GL_CONTEXT_MAJOR_VERSION, 3)
        sdl2.SDL_GL_SetAttribute(sdl2.SDL_GL_CONTEXT_MINOR_VERSION, 2)
        sdl2.SDL_GL_SetAttribute(sdl2.SDL_GL_CONTEXT_FORWARD_COMPATIBLE_FLAG, True)