`last_hit_buffer` in `quantum/rgb_matrix.c` does not properly maintain counts if a custom `rgb_matrix_map_row_column_to_led_kb` is defined that returns nonzero

[jhanschoo]

qmk_firmware/quantum/rgb_matrix.c

Line 233 in 8f5cc8d

last_hit_buffer.count--;

should read last_hit_buffer.count = LED_HITS_TO_REMEMBER - led_count;, so that after

qmk_firmware/quantum/rgb_matrix.c

Line 242 in 8f5cc8d

last_hit_buffer.count++;

that is executed led_count times, last_hit_buffer.count will be equal to LED_HITS_TO_REMEMBER

Present behavior:
the last_hit_buffer may remember less and less keys pressed and eventually stop remembering new keypresses if a custom rgb_matrix_map_row_column_to_led_kb is defined returning nonzero, causing problems with reactive RGB matrix effects with stale keypresses (older than the last LED_HITS_TO_REMEMBER keypresses) being remembered.

Expected behavior:
the last_hit_buffer should not have amnesia and always be able to maintain the last LED_HITS_TO_REMEMBER keypresses as long as rgb_matrix_map_row_column_to_led_kb always returns a value strictly less than LED_HITS_TO_REMEMBER (so that rgb_matrix_map_row_column_to_led always returns a value less then or equal to LED_HITS_TO_REMEMBER).

[jhanschoo]

I'll probably be able to manually verify this by implementing rgb_matrix_map_row_column_to_led_kb and flashing, but afaict no in-tree keyboards do this so it doesn't actually affect any in-tree keymaps.

[stale]

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