Character rendering optimizations and off-by-one fix#27
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slyglif wants to merge 2 commits intoUCTRONICS:mainfrom
Open
Character rendering optimizations and off-by-one fix#27slyglif wants to merge 2 commits intoUCTRONICS:mainfrom
slyglif wants to merge 2 commits intoUCTRONICS:mainfrom
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…_burst_transfer). Fix an off-by-one error in lcd_fill_rectangle. Remove an unnecessary REG_SYNC from lcd_write_string.
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No idea why this hasn't been merged in but this is a great contribution, @slyglif -- thanks! |
cafedomingo
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Buffer character pixels in memory and use burst transfer instead of pushing one pixel at a time. Remove redundant SYNC_REG call from lcd_write_string. Fix off-by-one clipping in lcd_fill_rectangle and wrong dimension calculation in lcd_draw_image. Adapted from UCTRONICS#27 Co-authored-by: slyglif <10196904+slyglif@users.noreply.github.com>
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cafedomingo
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Feb 23, 2026
Buffer character pixels in memory and use burst transfer instead of pushing one pixel at a time. Remove redundant SYNC_REG call from lcd_write_string. Fix off-by-one clipping in lcd_fill_rectangle and wrong dimension calculation in lcd_draw_image. Adapted from UCTRONICS#27 Co-authored-by: slyglif <10196904+slyglif@users.noreply.github.com>
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cafedomingo
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Feb 23, 2026
Buffer character pixels in memory and use burst transfer instead of pushing one pixel at a time. Remove redundant SYNC_REG call from lcd_write_string. Fix off-by-one clipping in lcd_fill_rectangle and wrong dimension calculation in lcd_draw_image. Use MemAvailable instead of MemFree for accurate RAM reporting. Adapted from UCTRONICS#27 and UCTRONICS#17 Co-authored-by: slyglif <10196904+slyglif@users.noreply.github.com> Co-authored-by: mobejm <4407468+mobejm@users.noreply.github.com>
cafedomingo
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Feb 23, 2026
Buffer character pixels in memory and use burst I2C transfer instead of pushing one pixel at a time. Use a stack buffer (832 bytes max) instead of malloc/free per character. Remove redundant SYNC_REG call from lcd_write_string. Fix off-by-one clipping in lcd_fill_rectangle and wrong dimension calculation in lcd_draw_image. Adapted from UCTRONICS#27 with endianness fix (the original PR stores native uint16_t values but i2c_burst_transfer expects big-endian byte order) and stack buffer simplification. Co-authored-by: slyglif <10196904+slyglif@users.noreply.github.com>
cafedomingo
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Feb 23, 2026
* Optimize character rendering and fix off-by-one bugs Buffer character pixels in memory and use burst I2C transfer instead of pushing one pixel at a time. Use a stack buffer (832 bytes max) instead of malloc/free per character. Remove redundant SYNC_REG call from lcd_write_string. Fix off-by-one clipping in lcd_fill_rectangle and wrong dimension calculation in lcd_draw_image. Adapted from UCTRONICS#27 with endianness fix (the original PR stores native uint16_t values but i2c_burst_transfer expects big-endian byte order) and stack buffer simplification. Co-authored-by: slyglif <10196904+slyglif@users.noreply.github.com> * Use MemAvailable instead of MemFree for RAM reporting MemAvailable includes reclaimable cache and buffers, giving a more accurate picture of actually available memory. Adapted from UCTRONICS#17 Co-authored-by: mobejm <4407468+mobejm@users.noreply.github.com> --------- Co-authored-by: slyglif <10196904+slyglif@users.noreply.github.com> Co-authored-by: mobejm <4407468+mobejm@users.noreply.github.com>
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Optimize lcd_write_char by rendering to a temporary memory buffer then using lcd_draw_image (and indirectly i2c_burst_transfer) instead of manually pushing a pixel at a time.
Remove an unnecessary REG_SYNC from lcd_write_string (it is handled indirectly by lcd_write_char).
Fix an off-by-one error in lcd_fill_rectangle (it effectively cropped the right most and bottom most pixels).