mirror of
https://github.com/storytold/wordcraft.git
synced 2026-11-10 04:09:53 -06:00
498 lines
22 KiB
Rust
498 lines
22 KiB
Rust
use super::select::{obj_size, selected, with_obj};
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use super::{CmdError, CmdResult, InlineObject, Rgb, Session, Value, Wrap, p};
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/// `picture.crop`: the crop, and optionally the new display size, as one edit. With a size, a
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/// floating picture positioned by offsets moves by what the crop on its left/top side on the page
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/// trims (or restores) — for a flipped picture that's the source's right/bottom — so what stays
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/// visible keeps its place on the page: a crop handle drop is one command.
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pub(super) fn crop(s: &mut Session, v: &Value) -> CmdResult {
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let mut c = [p::f32(v, "left"), p::f32(v, "top"), p::f32(v, "right"), p::f32(v, "bottom")].map(|x| x.unwrap_or(0.0).clamp(0.0, 0.95));
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// The two sides of an axis keep at least 5% of the source between them, as the renderer
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// draws it: the second side stops where the first one already left less than that.
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c[2] = c[2].min(0.95 - c[0]);
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c[3] = c[3].min(0.95 - c[1]);
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let size = |k: &str| p::f32(v, k).map(|x| x.clamp(1.0, 4000.0));
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let (nw, nh) = (size("width"), size("height"));
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with_obj(s, |o| {
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if let InlineObject::Image { crop, w, h, float, .. } = o {
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// The source's full size at the new display size (the visible part is 1-lo-hi of it).
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let full = |len: f32, lo: f32, hi: f32| len / (1.0 - lo - hi).max(0.05);
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// Flipped, the source's right (bottom) edge is the one on the page's left (top).
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let (left, top) = (if float.flip_h { 2 } else { 0 }, if float.flip_v { 3 } else { 1 });
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if let Some(nw) = nw {
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if float.wrap != Wrap::Inline && float.h_align.is_none() {
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float.x += (c[left] - crop[left]) * full(nw, c[0], c[2]);
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}
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*w = nw;
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}
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if let Some(nh) = nh {
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if float.wrap != Wrap::Inline && float.v_align.is_none() {
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float.y += (c[top] - crop[top]) * full(nh, c[1], c[3]);
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}
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*h = nh;
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}
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*crop = c;
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}
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})
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}
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/// A picture's original size: its image's pixels at 96 ppi (the size Insert › Pictures gives it)
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/// or a metafile's own frame, before any crop.
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#[derive(Clone, Copy, Debug, PartialEq)]
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pub struct OriginalSize {
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/// Points.
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pub w: f32,
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pub h: f32,
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/// A bitmap's pixels (None for a metafile).
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pub pixels: Option<(u32, u32)>,
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}
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/// The original size of the picture showing `media`, read from the image its Picture Format
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/// adjustments started from (Compress Pictures may have resampled the current one); None when the
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/// image can't be read.
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pub fn original_size(s: &Session, media: &str) -> Option<OriginalSize> {
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let key = s.originals.get(media).map_or(media, String::as_str);
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let bytes = s.doc.media.get(key).or_else(|| s.doc.media.get(media))?;
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if let Some((pw, ph)) = wordcraft_render::image_size(bytes) {
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return Some(OriginalSize { w: pw as f32 * 0.75, h: ph as f32 * 0.75, pixels: Some((pw, ph)) });
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}
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let (w, h, _) = wordcraft_render::metafile_size(bytes)?;
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Some(OriginalSize { w, h, pixels: None })
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}
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/// What a picture's crop leaves of its original size: the size Reset gives back and what a scale
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/// of the original counts from. None for anything but a picture whose image can be read.
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pub fn cropped_original_size(s: &Session, o: &InlineObject) -> Option<(f32, f32)> {
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let InlineObject::Image { media, crop, .. } = o else { return None };
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let orig = original_size(s, media)?;
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let part = |lo: f32, hi: f32| (1.0 - lo - hi).max(0.05);
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Some((orig.w * part(crop[0], crop[2]), orig.h * part(crop[1], crop[3])))
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}
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/// Size: `scale` is a percentage of the current size, or with `original` of what the crop leaves
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/// of the original size (`original` alone gives that back: the Size dialog's Reset); then `width`
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/// and `height`, where one alone keeps the proportions unless `lockAspect` is false.
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pub(super) fn size(s: &mut Session, v: &Value) -> CmdResult {
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let (_, o) = selected(s).ok_or_else(|| CmdError::Disabled("no object".into()))?;
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let lock = p::bool(v, "lockAspect").unwrap_or(true);
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let (mut w, mut h) = obj_size(&o);
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let scale = p::f32(v, "scale");
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if p::bool(v, "original").unwrap_or(false) {
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let (ow, oh) =
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cropped_original_size(s, &o).ok_or_else(|| CmdError::Disabled("only a picture whose image can be read has an original size".into()))?;
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let k = scale.unwrap_or(100.0) / 100.0;
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(w, h) = (ow * k, oh * k);
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} else if let Some(sc) = scale {
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w *= sc / 100.0;
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h *= sc / 100.0;
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}
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let (nw, nh) = (p::f32(v, "width"), p::f32(v, "height"));
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match (nw, nh) {
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(Some(nw), Some(nh)) => {
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w = nw;
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h = nh;
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}
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(Some(nw), None) => {
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if lock && w > 0.0 {
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h *= nw / w;
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}
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w = nw;
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}
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(None, Some(nh)) => {
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if lock && h > 0.0 {
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w *= nh / h;
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}
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h = nh;
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}
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_ => {}
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}
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// A size that keeps the proportions shrinks on both sides to fit, rather than flattening.
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let keep = match (nw, nh) {
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(Some(_), Some(_)) => false,
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(None, None) => true,
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_ => lock,
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};
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let (w, h) = fit_size(w, h, keep);
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// Any drawing: a group's members scale with its frame (its child space is kept); a chart or
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// SmartArt graphic lays itself out again at the new size.
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let theme = s.doc.settings.theme_colors.clone();
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with_obj(s, |o| {
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o.set_size(w, h);
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crate::cmd::chart::redraw(o, &theme);
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crate::cmd::smart_art::redraw(o, &theme);
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})
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}
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/// An object size within 1–4000 pt. With `keep`, both sides scale by one factor, the one nearest
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/// 1 that brings them within the limits, so the proportions hold; a shape too long and thin for any
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/// such factor is clamped side by side.
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pub fn fit_size(w: f32, h: f32, keep: bool) -> (f32, f32) {
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let side = |x: f32| if x.is_nan() { 1.0 } else { x.clamp(1.0, 4000.0) };
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if keep && w.is_finite() && h.is_finite() && w > 0.0 && h > 0.0 {
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let (lo, hi) = ((1.0 / w).max(1.0 / h), (4000.0 / w).min(4000.0 / h));
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if lo <= hi {
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let k = if lo > 1.0 {
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lo
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} else if hi < 1.0 {
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hi
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} else {
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1.0
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};
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return (side(w * k), side(h * k));
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}
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}
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(side(w), side(h))
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}
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/// Apply an image operation to the selected picture's bitmap (stored as a new PNG).
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pub(super) fn adjust(s: &mut Session, f: impl Fn(image::DynamicImage) -> Result<image::DynamicImage, CmdError>) -> CmdResult {
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let (_, o) = selected(s).ok_or_else(|| CmdError::Disabled("no picture".into()))?;
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let InlineObject::Image { media, .. } = o else { return Err(CmdError::Disabled("not a picture".into())) };
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adjust_media(s, &media, f)
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}
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/// Like [`adjust`], but decodes `base` (a media key, usually the pre-edit original) instead
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/// of the picture's current bitmap. The result still chains onto the originals map, so Reset
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/// Picture keeps working.
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pub(super) fn adjust_media(s: &mut Session, base: &str, f: impl Fn(image::DynamicImage) -> Result<image::DynamicImage, CmdError>) -> CmdResult {
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let bytes = s.doc.media.get(base).cloned().ok_or_else(|| CmdError::Failed("picture data missing".into()))?;
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// Within the budget pictures are drawn within, checked from the header first (#3644, #3647).
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let img = wordcraft_geom::picture::decode(&bytes, wordcraft_geom::MAX_DECODED_BYTES).map_err(|e| match e {
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wordcraft_geom::picture::Refusal::TooLarge { .. } => too_large(),
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e => CmdError::Failed(format!("can't decode the picture: {e}")),
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})?;
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let out = f(img)?;
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let mut png = Vec::new();
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out.write_to(&mut std::io::Cursor::new(&mut png), image::ImageFormat::Png).map_err(|e| CmdError::Failed(e.to_string()))?;
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let key = s.doc.add_media(png, "png");
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// Chain onto the ultimate original (the base's, or the current picture's when the base
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// is itself derived), so Reset Picture always finds it.
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let cur = selected(s).and_then(|(_, o)| match o {
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InlineObject::Image { media, .. } => Some(media),
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_ => None,
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});
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let orig = s
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.originals
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.get(base)
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.cloned()
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.or_else(|| cur.as_ref().and_then(|m| s.originals.get(m).cloned()))
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.unwrap_or_else(|| cur.clone().unwrap_or_else(|| key.clone()));
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s.originals.entry(key.clone()).or_insert(orig);
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with_obj(s, |o| {
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if let InlineObject::Image { media, .. } = o {
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*media = key.clone();
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}
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})
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}
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fn too_large() -> CmdError {
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CmdError::Failed("picture is too large to edit".into())
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}
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/// A `w` × `h` bitmap of `fill` for an edit to draw on, refused when the picture it makes would be
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/// too large to draw (two RGBA buffers within the decode budget), before it is allocated (#3611).
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fn canvas(w: u32, h: u32, fill: [u8; 4]) -> Result<image::RgbaImage, CmdError> {
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if !wordcraft_geom::decode_fits(w, h, wordcraft_geom::MAX_DECODED_BYTES) {
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return Err(too_large());
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}
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Ok(image::RgbaImage::from_pixel(w, h, image::Rgba(fill)))
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}
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/// `w` and `h` grown by `pad` on every side, None past `u32`.
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pub(super) fn grown(w: u32, h: u32, pad: u32) -> Option<(u32, u32)> {
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let twice = pad.checked_mul(2)?;
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Some((w.checked_add(twice)?, h.checked_add(twice)?))
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}
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/// What Artistic Effects, Picture Styles and Picture Border drew on a picture's bitmap: the
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/// bitmap they started from and the effect, style and border on it, so the next one draws again
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/// from that bitmap instead of over the last result. Picking a second style replaces the first,
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/// as in Word, instead of framing the frame (#2052). Kept in [`Session::picture_looks`] under the
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/// media key of the drawn bitmap.
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#[derive(Clone, Debug, Default)]
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pub struct PictureLook {
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/// The media key of the bitmap before any of them.
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pub base: String,
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pub effect: Option<String>,
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pub style: Option<String>,
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pub border: Option<(Rgb, u32)>,
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/// The drawn bitmap: a media key that names other bytes later (undo then a new picture
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/// reusing the key) is not this look's.
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pub drawn: std::sync::Arc<Vec<u8>>,
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}
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/// Change the selected picture's effect, style or border and draw it again from the bitmap
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/// under them (effect, then style, then border).
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pub(super) fn relook(s: &mut Session, change: impl FnOnce(&mut PictureLook)) -> CmdResult {
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let (_, o) = selected(s).ok_or_else(|| CmdError::Disabled("no picture".into()))?;
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let InlineObject::Image { media, .. } = o else { return Err(CmdError::Disabled("not a picture".into())) };
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let cur = s.doc.media.get(&media).cloned();
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let mut look = s
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.picture_looks
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.get(&media)
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.filter(|l| cur.as_ref().is_some_and(|c| std::sync::Arc::ptr_eq(c, &l.drawn)) && s.doc.media.contains_key(&l.base))
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.cloned()
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.unwrap_or_else(|| PictureLook { base: media.clone(), ..Default::default() });
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change(&mut look);
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if look.effect.is_none() && look.style.is_none() && look.border.is_none() {
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// Nothing left on it: the bitmap as it was.
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let base = look.base.clone();
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return with_obj(s, |o| {
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if let InlineObject::Image { media, .. } = o {
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*media = base.clone();
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}
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});
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}
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let l = look.clone();
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let out = adjust_media(s, &look.base, move |img| {
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let mut img = match &l.effect {
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Some(e) => artistic_effect(img, e),
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None => img,
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};
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if let Some(st) = &l.style {
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img = picture_style(img, st)?;
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}
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if let Some((c, w)) = l.border {
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img = frame(img, w, [c.0, c.1, c.2, 255])?;
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}
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Ok(img)
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})?;
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if let Some((_, InlineObject::Image { media, .. })) = selected(s)
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&& let Some(drawn) = s.doc.media.get(&media).cloned()
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{
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s.picture_looks.insert(media, PictureLook { drawn, ..look });
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}
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Ok(out)
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}
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fn artistic_effect(img: image::DynamicImage, effect: &str) -> image::DynamicImage {
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match effect {
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"blur" => img.blur(3.0),
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"sharpen" => img.unsharpen(2.0, 2),
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"invert" => {
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let mut i = img;
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i.invert();
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i
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}
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"posterize" => {
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let mut rgba = img.to_rgba8();
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for px in rgba.pixels_mut() {
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for c in px.0.iter_mut().take(3) {
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*c = (*c / 64) * 85;
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}
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}
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image::DynamicImage::ImageRgba8(rgba)
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}
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"pixelate" => {
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let (w, h) = (img.width().max(1), img.height().max(1));
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img.resize_exact((w / 12).max(1), (h / 12).max(1), image::imageops::FilterType::Nearest).resize_exact(
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w,
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h,
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image::imageops::FilterType::Nearest,
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)
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}
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_ => img,
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}
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}
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pub(super) fn reset(s: &mut Session, _: &Value) -> CmdResult {
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let (_, o) = selected(s).ok_or_else(|| CmdError::Disabled("no picture".into()))?;
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let InlineObject::Image { media, .. } = o else { return Err(CmdError::Disabled("not a picture".into())) };
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let orig = s.originals.get(&media).cloned().unwrap_or(media);
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with_obj(s, |o| {
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if let InlineObject::Image { media, crop, .. } = o {
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*media = orig.clone();
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*crop = [0.0; 4];
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}
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})
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}
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pub(super) fn recolor(img: image::DynamicImage, mode: &str, sat: f32) -> image::DynamicImage {
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let mut rgba = img.to_rgba8();
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for px in rgba.pixels_mut() {
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let [r, g, b, a] = px.0;
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let (rf, gf, bf) = (r as f32, g as f32, b as f32);
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let l = 0.299 * rf + 0.587 * gf + 0.114 * bf;
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let out = match mode {
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"grayscale" => [l, l, l],
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"sepia" => [
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(0.393 * rf + 0.769 * gf + 0.189 * bf).min(255.0),
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(0.349 * rf + 0.686 * gf + 0.168 * bf).min(255.0),
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(0.272 * rf + 0.534 * gf + 0.131 * bf).min(255.0),
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],
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"washout" => [rf * 0.35 + 255.0 * 0.65, gf * 0.35 + 255.0 * 0.65, bf * 0.35 + 255.0 * 0.65],
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"blackAndWhite" => {
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let v = if l > 127.0 { 255.0 } else { 0.0 };
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[v, v, v]
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}
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"tint" => [l * 0.6 + 0.4 * 0x3B as f32, l * 0.6 + 0.4 * 0x5B as f32, l * 0.6 + 0.4 * 0xDB as f32],
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_ => {
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let k = sat / 100.0;
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[l + (rf - l) * k, l + (gf - l) * k, l + (bf - l) * k]
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}
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};
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px.0 = [out[0].clamp(0.0, 255.0) as u8, out[1].clamp(0.0, 255.0) as u8, out[2].clamp(0.0, 255.0) as u8, a];
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}
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image::DynamicImage::ImageRgba8(rgba)
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}
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/// Flood the border-connected region close to the corner colour with transparency.
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pub(super) fn remove_background(img: image::DynamicImage, tol: f32) -> image::DynamicImage {
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let mut rgba = img.to_rgba8();
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clear_background(&mut rgba, tol);
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image::DynamicImage::ImageRgba8(rgba)
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}
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/// [`remove_background`] on `rgba`, a row span at a time: besides the border's seeds, the stack
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/// holds one for each run of matching pixels beside a filled span, instead of four for every
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/// pixel filled (#3647). Returns the most seeds it held.
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pub(super) fn clear_background(rgba: &mut image::RgbaImage, tol: f32) -> usize {
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let (w, h) = rgba.dimensions();
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let Some(bg) = rgba.get_pixel_checked(0, 0).map(|p| p.0) else { return 0 };
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let close = |p: [u8; 4]| (0..3).map(|i| (p[i] as f32 - bg[i] as f32).abs()).fold(0.0f32, f32::max) <= tol;
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let at = |x: u32, y: u32| y as usize * w as usize + x as usize;
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// Not cleared yet, and close to the corner colour.
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let open = |rgba: &image::RgbaImage, seen: &[bool], x: u32, y: u32| {
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!seen.get(at(x, y)).copied().unwrap_or(true) && rgba.get_pixel_checked(x, y).is_some_and(|p| close(p.0))
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};
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let mut seen = vec![false; (w as usize) * (h as usize)];
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let mut stack = border_pixels(w, h);
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let mut most = stack.len();
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while let Some((x, y)) = stack.pop() {
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if !open(rgba, &seen, x, y) {
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continue;
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}
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let (x0, x1) = run_span(x, y, w, |xi, yi| open(rgba, &seen, xi, yi));
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for xi in x0..=x1 {
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if let Some(s) = seen.get_mut(at(xi, y)) {
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*s = true;
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}
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if let Some(p) = rgba.get_pixel_mut_checked(xi, y) {
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p.0[3] = 0;
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}
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}
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for ny in [y.checked_sub(1), y.checked_add(1).filter(|&n| n < h)].into_iter().flatten() {
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push_open_runs(&mut stack, x0, x1, ny, |xi, yi| open(rgba, &seen, xi, yi));
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}
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most = most.max(stack.len());
|
||
}
|
||
most
|
||
}
|
||
|
||
/// Every pixel on the image's edge, the flood-fill seeds.
|
||
fn border_pixels(w: u32, h: u32) -> Vec<(u32, u32)> {
|
||
let mut stack = Vec::new();
|
||
for x in 0..w {
|
||
stack.push((x, 0));
|
||
stack.push((x, h - 1));
|
||
}
|
||
for y in 0..h {
|
||
stack.push((0, y));
|
||
stack.push((w - 1, y));
|
||
}
|
||
stack
|
||
}
|
||
|
||
/// The horizontal run of open pixels around `(x, y)`, both ends included.
|
||
fn run_span(x: u32, y: u32, w: u32, open: impl Fn(u32, u32) -> bool) -> (u32, u32) {
|
||
let (mut x0, mut x1) = (x, x);
|
||
while x0 > 0 && open(x0 - 1, y) {
|
||
x0 -= 1;
|
||
}
|
||
while x1 + 1 < w && open(x1 + 1, y) {
|
||
x1 += 1;
|
||
}
|
||
(x0, x1)
|
||
}
|
||
|
||
/// Queues the first pixel of each open run in row `ny` between `x0` and `x1`.
|
||
fn push_open_runs(stack: &mut Vec<(u32, u32)>, x0: u32, x1: u32, ny: u32, open: impl Fn(u32, u32) -> bool) {
|
||
let mut xi = x0;
|
||
while xi <= x1 {
|
||
if open(xi, ny) {
|
||
stack.push((xi, ny));
|
||
while xi <= x1 && open(xi, ny) {
|
||
xi += 1;
|
||
}
|
||
} else {
|
||
xi += 1;
|
||
}
|
||
}
|
||
}
|
||
|
||
fn frame(img: image::DynamicImage, border: u32, color: [u8; 4]) -> Result<image::DynamicImage, CmdError> {
|
||
let (w, h) = grown(img.width(), img.height(), border).ok_or_else(too_large)?;
|
||
let mut out = canvas(w, h, color)?;
|
||
image::imageops::overlay(&mut out, &img.to_rgba8(), border as i64, border as i64);
|
||
Ok(image::DynamicImage::ImageRgba8(out))
|
||
}
|
||
|
||
pub(super) fn picture_style(img: image::DynamicImage, style: &str) -> Result<image::DynamicImage, CmdError> {
|
||
let m = (img.width().max(img.height()) / 40).max(4);
|
||
Ok(match style {
|
||
"thickFrame" => frame(frame(img, m * 2, [255, 255, 255, 255])?, m / 2, [40, 40, 40, 255])?,
|
||
"rounded" | "softEdge" => {
|
||
let mut rgba = img.to_rgba8();
|
||
let (w, h) = rgba.dimensions();
|
||
let r = (w.min(h) as f32) * if style == "rounded" { 0.12 } else { 0.0 };
|
||
let feather = if style == "softEdge" { (w.min(h) as f32 * 0.08).max(2.0) } else { 1.5 };
|
||
for y in 0..h {
|
||
for x in 0..w {
|
||
let (fx, fy) = (x as f32 + 0.5, y as f32 + 0.5);
|
||
let dx = (r - fx).max(fx - (w as f32 - r)).max(0.0);
|
||
let dy = (r - fy).max(fy - (h as f32 - r)).max(0.0);
|
||
let edge = (fx.min(w as f32 - fx)).min(fy.min(h as f32 - fy));
|
||
let inside = if r > 0.0 && dx > 0.0 && dy > 0.0 { r - (dx * dx + dy * dy).sqrt() } else { edge };
|
||
let k = (inside / feather).clamp(0.0, 1.0);
|
||
let p = rgba.get_pixel_mut(x, y);
|
||
p.0[3] = (p.0[3] as f32 * k) as u8;
|
||
}
|
||
}
|
||
image::DynamicImage::ImageRgba8(rgba)
|
||
}
|
||
"shadow" => {
|
||
let (w, h) = (img.width(), img.height());
|
||
let off = m;
|
||
let (pw, ph) = grown(w, h, off).ok_or_else(too_large)?;
|
||
let mut out = canvas(pw, ph, [0, 0, 0, 0])?;
|
||
// A rectangle of alpha 90 the picture's size, one and a half margins in, blurred. Its
|
||
// blur is the product of its sides' blurs along each axis, so it is drawn from two
|
||
// profiles, not by blurring every pixel with a kernel that grows with the picture (#3647).
|
||
let (sigma, start) = (off as f32 / 2.0, off + off / 2);
|
||
let (xs, ys) = (blurred_span(pw, start, w, sigma), blurred_span(ph, start, h, sigma));
|
||
for (x, y, p) in out.enumerate_pixels_mut() {
|
||
let k = xs.get(x as usize).copied().unwrap_or(0.0) * ys.get(y as usize).copied().unwrap_or(0.0);
|
||
p.0[3] = (90.0 * k).round() as u8;
|
||
}
|
||
image::imageops::overlay(&mut out, &img.to_rgba8(), 0, 0);
|
||
image::DynamicImage::ImageRgba8(out)
|
||
}
|
||
_ => frame(img, m, [255, 255, 255, 255])?,
|
||
})
|
||
}
|
||
|
||
/// How much of a span `len` long from `start` covers each of `n` positions once blurred with the
|
||
/// Gaussian `image::imageops::blur` uses for `sigma` (outside the `n` positions counts as clear):
|
||
/// 0 to 1. Each position is one difference of the kernel's running sums.
|
||
fn blurred_span(n: u32, start: u32, len: u32, sigma: f32) -> Vec<f32> {
|
||
let kernel = gaussian_kernel(sigma);
|
||
let mut sums = vec![0.0f32];
|
||
for k in &kernel {
|
||
sums.push(sums.last().copied().unwrap_or(0.0) + k);
|
||
}
|
||
let (size, r) = (kernel.len() as i64, (kernel.len() / 2) as i64);
|
||
let sum_to = |k: i64| sums.get(k.clamp(0, size) as usize).copied().unwrap_or(0.0);
|
||
let (start, end) = (i64::from(start), i64::from(start) + i64::from(len));
|
||
// Position i takes weight k from i + k - r, inside the span for k in [start - i + r, end - i + r).
|
||
(0..i64::from(n)).map(|i| sum_to(end - i + r) - sum_to(start - i + r)).collect()
|
||
}
|
||
|
||
/// The normalized kernel `image::imageops::blur` (0.25) uses for `sigma`: odd, about 6.7 σ wide.
|
||
fn gaussian_kernel(sigma: f32) -> Vec<f32> {
|
||
let size = ((((sigma - 0.8) / 0.3 + 1.0) * 2.0 + 1.0).max(3.0) as usize) | 1;
|
||
let mean = (size / 2) as f32;
|
||
let weights: Vec<f32> = (0..size).map(|x| (-0.5 * ((x as f32 - mean) / sigma).powi(2)).exp()).collect();
|
||
let total: f32 = weights.iter().sum();
|
||
weights.into_iter().map(|v| v / total).collect()
|
||
}
|