diff options
| author | Vito Caputo <vcaputo@pengaru.com> | 2023-10-03 17:13:19 -0700 |
|---|---|---|
| committer | Vito Caputo <vcaputo@pengaru.com> | 2023-10-03 17:13:19 -0700 |
| commit | 271889386861ab8685cebddcebeaa87eea3fa417 (patch) | |
| tree | 7c1a9bb573dd16b554592b24cc3c5083483779b2 /src | |
| parent | 30214bf817c1e18235fcddacac851ecc5cbe66a0 (diff) | |
libs/txt: implement txt_render_fragment_offsetted() variant
Instead of rigid txt_align_t enums to specify how the text is
aligned relative to the x/y coordinates, you specify float
offsets in normalized coordinates -1..+1 allowing fine-grained
control of the offsets.
modules/asc will use this to automatically adjust the offsets
when requested, so x/y coordinates may be varied dynamically
using taps with the text automagically adjusting its offset to
try stay in-fragment.
Diffstat (limited to 'src')
| -rw-r--r-- | src/libs/txt/txt.c | 26 | ||||
| -rw-r--r-- | src/libs/txt/txt.h | 1 |
2 files changed, 27 insertions, 0 deletions
diff --git a/src/libs/txt/txt.c b/src/libs/txt/txt.c index d575821..2e74340 100644 --- a/src/libs/txt/txt.c +++ b/src/libs/txt/txt.c @@ -210,3 +210,29 @@ void txt_render_fragment_aligned(txt_t *txt, til_fb_fragment_t *fragment, uint32 return txt_render(txt, fragment, color, jx, jy); } + + +/* Like txt_render_fragment_aligned(), except instead of specifying halign/valign enum variants, + * you provide -1..+1 normalized offsets within the rendered text rectangle to anchor the + * provided x,y pixel coordinates. This enables progressively varying the justification + * offset rather than it behaving like a step function of three options left/right/center or + * top/bottom/center etc. (modules/asc was the impetus for adding this) + */ +void txt_render_fragment_offsetted(txt_t *txt, til_fb_fragment_t *fragment, uint32_t color, int x, int y, float x_offset, float y_offset) +{ + int jx = x, jy = y; + + assert(txt); + + /* XXX: one could argue the offsets should be clamped to -1..+1, but + * I can see valid use cases where one wants to go grater than abs(1) + * to achieve extremely offset texts in dynamic situations. So I'm + * just letting whatever comes in pass thru for now, considering this + * is "art" oriented where allowing creative stuff to just work trumps + * preventing potential buggy behavior. + */ + jx -= x_offset * txt->width * .5f + txt->width * .5f; + jy -= y_offset * txt->height * .5f + txt->height * .5f; + + return txt_render(txt, fragment, color, jx, jy); +} diff --git a/src/libs/txt/txt.h b/src/libs/txt/txt.h index 9318546..04cf09e 100644 --- a/src/libs/txt/txt.h +++ b/src/libs/txt/txt.h @@ -29,5 +29,6 @@ txt_t * txt_new(const char *str); txt_t * txt_newf(const char *fmt, ...); txt_t * txt_free(txt_t *txt); void txt_render_fragment_aligned(txt_t *txt, til_fb_fragment_t *fragment, uint32_t color, int x, int y, txt_align_t alignment); +void txt_render_fragment_offsetted(txt_t *txt, til_fb_fragment_t *fragment, uint32_t color, int x, int y, float x_offset, float y_offset); #endif |