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Re: fast C (or other readable language) version of SCR DOT POSITION with screen_offset!=0?

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I also asked on the cpc wiki forum. And got a nice answer by
lightforce6128. [1]

Thanks to him I ended up with something like:

inline char* scr_dot_position(uint16_t scroff, uint16_t x, uint8_t y) {
       uint16_t x_offset    = x / 8;
       uint16_t y_offset    = (uint16_t)(y / 8) * 80;
       uint16_t y_scanline  = (uint16_t)(y % 8) * 2048;
       return (char*)0xC000
              + ((scroff + x_offset + y_offset) % 2048) + y_scanline;
}

Regarding the hardware scroll the result is at [2]

[1] https://www.cpcwiki.eu/forum/programming/fast-c-version-of-scr-dot-position-with-screen_offset!0/
[2] https://www.karme.de/cpc/#scrolling

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fast C (or other readable language) version of SCR DOT POSITION with screen_offset!=0? Jens Thiele <karme@karme.de> - 2025-10-02 12:50 +0200
  Re: fast C (or other readable language) version of SCR DOT POSITION with screen_offset!=0? Jens Thiele <karme@karme.de> - 2025-10-02 12:56 +0200

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