render_agnostic/renderers/
image.rs

1use std::{
2    f64::consts::{FRAC_PI_2, PI},
3    iter::once,
4};
5
6use ab_glyph::FontArc;
7use anchor2d::{Anchor2D, HorizontalAnchor, VerticalAnchorContext, VerticalAnchorValue};
8use glam::{DVec2, IVec2, dvec2, ivec2};
9use image::{
10    Rgba, RgbaImage,
11    imageops::{FilterType, overlay, resize},
12};
13use imageproc::{
14    drawing::{
15        draw_filled_circle_mut, draw_filled_rect_mut, draw_polygon_mut, draw_text_mut, text_size,
16    },
17    point::Point,
18    rect::Rect,
19};
20use itertools::Itertools;
21use palette::Srgba;
22
23use crate::Renderer;
24
25fn srgba_to_rgba8(color: Srgba) -> Rgba<u8> {
26    let red = (color.red * 255.0).round().clamp(0.0, 255.0) as u8;
27    let green = (color.green * 255.0).round().clamp(0.0, 255.0) as u8;
28    let blue = (color.blue * 255.0).round().clamp(0.0, 255.0) as u8;
29    let alpha = (color.alpha * 255.0).round().clamp(0.0, 255.0) as u8;
30    Rgba([red, green, blue, alpha])
31}
32
33#[derive(Clone)]
34pub struct ImageRenderer {
35    virtual_width: u32,
36    virtual_height: u32,
37    image: RgbaImage,
38    scale: f64,
39    scaling_target: DVec2,
40    supersampling: u32,
41    font: FontArc,
42}
43
44impl ImageRenderer {
45    pub fn new(
46        width: u32,
47        height: u32,
48        scale: f64,
49        scaling_target: DVec2,
50        supersampling: u32,
51        font: FontArc,
52    ) -> Self {
53        Self {
54            virtual_width: width,
55            virtual_height: height,
56            image: RgbaImage::new(width * supersampling, height * supersampling),
57            scale,
58            scaling_target,
59            supersampling,
60            font,
61        }
62    }
63
64    pub fn get_font(&self) -> &FontArc {
65        &self.font
66    }
67
68    pub fn set_font(&mut self, font: FontArc) {
69        self.font = font;
70    }
71
72    fn get_supersampled_width(&self) -> u32 {
73        self.virtual_width * self.supersampling
74    }
75
76    fn get_supersampled_height(&self) -> u32 {
77        self.virtual_height * self.supersampling
78    }
79
80    fn map_value(&self, value: f64) -> f64 {
81        value * self.scale * self.supersampling as f64
82    }
83
84    fn map_x(&self, x: f64) -> f64 {
85        let target_x = self.get_supersampled_width() as f64 * self.scaling_target.x;
86        (x * self.supersampling as f64 - target_x) * self.scale + target_x
87    }
88
89    fn map_y(&self, y: f64) -> f64 {
90        let target_y = self.get_supersampled_height() as f64 * self.scaling_target.y;
91        (y * self.supersampling as f64 - target_y) * self.scale + target_y
92    }
93
94    fn map_dvec2(&self, v: DVec2) -> DVec2 {
95        dvec2(self.map_x(v.x), self.map_y(v.y))
96    }
97
98    pub fn reset(&mut self) {
99        self.image = self.transparent();
100    }
101
102    pub fn get_image(&self) -> &RgbaImage {
103        &self.image
104    }
105
106    pub fn render_image_onto(&self, mut image: RgbaImage) -> RgbaImage {
107        overlay(&mut image, &self.image, 0, 0);
108
109        resize(
110            &image,
111            self.virtual_width,
112            self.virtual_height,
113            FilterType::Lanczos3,
114        )
115    }
116
117    pub fn transparent(&self) -> RgbaImage {
118        RgbaImage::new(
119            self.get_supersampled_width(),
120            self.get_supersampled_height(),
121        )
122    }
123
124    pub fn black(&self) -> RgbaImage {
125        RgbaImage::from_pixel(
126            self.get_supersampled_width(),
127            self.get_supersampled_height(),
128            Rgba([0, 0, 0, 255]),
129        )
130    }
131
132    fn get_base_points(&self, position: DVec2, width: f64, height: f64) -> Vec<DVec2> {
133        vec![
134            position,
135            position + DVec2::X * width,
136            position + DVec2::X * width + DVec2::Y * height,
137            position + DVec2::Y * height,
138        ]
139    }
140
141    fn get_offset_vec(&self, width: f64, height: f64, offset: DVec2) -> DVec2 {
142        let offset_width = width * offset.x;
143        let offset_height = height * offset.y;
144
145        dvec2(offset_width, offset_height)
146    }
147
148    fn get_offset_points(&self, points: &[DVec2], offset_vec: DVec2) -> Vec<DVec2> {
149        points
150            .iter()
151            .copied()
152            .map(|base_point| base_point - offset_vec)
153            .collect::<Vec<DVec2>>()
154    }
155
156    fn get_rotated_points(&self, points: &[DVec2], axis: DVec2, rotation: f64) -> Vec<DVec2> {
157        points
158            .iter()
159            .copied()
160            .map(|point| rotate_point_around(point, axis, rotation))
161            .collect::<Vec<DVec2>>()
162    }
163
164    fn get_unique_integer_points(&self, points: &[DVec2]) -> Vec<IVec2> {
165        points
166            .iter()
167            .map(|point| point.round().as_ivec2())
168            .unique()
169            .collect::<Vec<IVec2>>()
170    }
171}
172
173impl Renderer for ImageRenderer {
174    fn render_point(&mut self, position: DVec2, color: Srgba) {
175        let position = self.map_dvec2(position);
176        let width = self.map_value(1.0);
177        let height = self.map_value(1.0);
178
179        let integer_position = position.round().as_ivec2();
180
181        draw_filled_rect_mut(
182            &mut self.image,
183            Rect::at(integer_position.x, integer_position.y)
184                .of_size(width.round() as u32, height.round() as u32),
185            srgba_to_rgba8(color),
186        );
187    }
188
189    fn render_line(&mut self, start: DVec2, end: DVec2, thickness: f64, color: Srgba) {
190        let start = self.map_dvec2(start);
191        let end = self.map_dvec2(end);
192
193        let thickness = self.map_value(thickness);
194        let offset = thickness / 2.0;
195        let normal = DVec2::from_angle((end - start).to_angle() + FRAC_PI_2);
196
197        let points = vec![
198            start + normal * offset,
199            start - normal * offset,
200            end - normal * offset,
201            end + normal * offset,
202        ];
203
204        let integer_points = self
205            .get_unique_integer_points(&points)
206            .iter()
207            .map(|integer_point| Point::new(integer_point.x, integer_point.y))
208            .collect::<Vec<Point<i32>>>();
209
210        if integer_points.len() == 1 {
211            let integer_point = integer_points.first().unwrap();
212
213            self.render_point(dvec2(integer_point.x as f64, integer_point.y as f64), color);
214        } else {
215            draw_polygon_mut(&mut self.image, &integer_points, srgba_to_rgba8(color));
216        }
217    }
218
219    fn render_circle(&mut self, position: DVec2, radius: f64, color: Srgba) {
220        let position = self.map_dvec2(position).round().as_ivec2();
221        let radius = self.map_value(radius).round() as u32;
222
223        draw_filled_circle_mut(
224            &mut self.image,
225            position.into(),
226            radius as i32,
227            srgba_to_rgba8(color),
228        );
229    }
230
231    fn render_circle_lines(&mut self, position: DVec2, radius: f64, thickness: f64, color: Srgba) {
232        let position = self.map_dvec2(position).round().as_ivec2();
233        let radius = self.map_value(radius).round();
234        let thickness = self.map_value(thickness).round();
235
236        let mut circle_renderer = ImageRenderer::new(
237            2 * radius as u32 + 1,
238            2 * radius as u32 + 1,
239            self.scale,
240            self.scaling_target,
241            self.supersampling,
242            self.font.clone(),
243        );
244
245        circle_renderer.render_circle(dvec2(radius, radius), radius, color);
246
247        circle_renderer.render_circle(
248            dvec2(radius, radius),
249            radius - thickness,
250            Srgba::new(0.0, 0.0, 0.0, 0.0),
251        );
252
253        overlay(
254            &mut self.image,
255            &circle_renderer.render_image_onto(circle_renderer.transparent()),
256            (position.x - radius as i32) as i64,
257            (position.y - radius as i32) as i64,
258        );
259    }
260
261    fn render_arc(&mut self, position: DVec2, radius: f64, rotation: f64, arc: f64, color: Srgba) {
262        let position = self.map_dvec2(position);
263        let radius = self.map_value(radius);
264
265        let points =
266            once(position)
267                .chain((0..32).map(|i| {
268                    position + radius * DVec2::from_angle(rotation + arc * i as f64 / 31.0)
269                }))
270                .collect::<Vec<DVec2>>();
271
272        let integer_points = self
273            .get_unique_integer_points(&points)
274            .iter()
275            .map(|integer_point| Point::new(integer_point.x, integer_point.y))
276            .collect::<Vec<Point<i32>>>();
277
278        if integer_points.len() == 1 {
279            let integer_point = integer_points.first().unwrap();
280
281            self.render_point(dvec2(integer_point.x as f64, integer_point.y as f64), color);
282        } else {
283            draw_polygon_mut(&mut self.image, &integer_points, srgba_to_rgba8(color));
284        }
285    }
286
287    fn render_arc_lines(
288        &mut self,
289        position: DVec2,
290        radius: f64,
291        rotation: f64,
292        arc: f64,
293        thickness: f64,
294        color: Srgba,
295    ) {
296        let position = self.map_dvec2(position).round().as_ivec2();
297        let radius = self.map_value(radius).round();
298        let thickness = self.map_value(thickness).round();
299
300        let mut circle_renderer = ImageRenderer::new(
301            2 * radius as u32 + 1,
302            2 * radius as u32 + 1,
303            self.scale,
304            self.scaling_target,
305            self.supersampling,
306            self.font.clone(),
307        );
308
309        circle_renderer.render_arc(dvec2(radius, radius), radius, rotation, arc, color);
310
311        circle_renderer.render_circle(
312            dvec2(radius, radius),
313            radius - thickness,
314            Srgba::new(0.0, 0.0, 0.0, 0.0),
315        );
316
317        overlay(
318            &mut self.image,
319            &circle_renderer.render_image_onto(circle_renderer.transparent()),
320            (position.x - radius as i32) as i64,
321            (position.y - radius as i32) as i64,
322        );
323    }
324
325    fn render_text(
326        &mut self,
327        text: &str,
328        position: DVec2,
329        anchor: Anchor2D,
330        size: f64,
331        color: Srgba,
332    ) {
333        let position = self.map_dvec2(position);
334        let size = self.map_value(size);
335
336        let (text_width, _) = text_size(size as f32, &self.font, text);
337
338        let x = match anchor.get_horizontal() {
339            HorizontalAnchor::Left => position.x,
340            HorizontalAnchor::Center => position.x - text_width as f64 / 2.0,
341            HorizontalAnchor::Right => position.x - text_width as f64,
342        };
343
344        let vertical_anchor = anchor.get_vertical();
345
346        let y = match (vertical_anchor.get_context(), vertical_anchor.get_value()) {
347            (VerticalAnchorContext::Graphics, VerticalAnchorValue::Bottom) => {
348                position.y - size / 1.25
349            }
350            (VerticalAnchorContext::Math, VerticalAnchorValue::Bottom) => position.y,
351            (_, VerticalAnchorValue::Center) => position.y - size / 1.25 / 2.0,
352            (VerticalAnchorContext::Graphics, VerticalAnchorValue::Top) => position.y,
353            (VerticalAnchorContext::Math, VerticalAnchorValue::Top) => position.y - size / 1.25,
354        };
355
356        draw_text_mut(
357            &mut self.image,
358            srgba_to_rgba8(color),
359            x as i32,
360            y as i32,
361            size as f32,
362            &self.font,
363            text,
364        );
365    }
366
367    fn render_text_outline(
368        &mut self,
369        text: &str,
370        position: DVec2,
371        anchor: Anchor2D,
372        size: f64,
373        outline_thickness: f64,
374        color: Srgba,
375        outline_color: Srgba,
376    ) {
377        let position = self.map_dvec2(position);
378        let size = self.map_value(size);
379        let outline_thickness = self.map_value(outline_thickness);
380
381        let (text_width, _) = text_size(size as f32, &self.font, text);
382
383        let x = match anchor.get_horizontal() {
384            HorizontalAnchor::Left => position.x,
385            HorizontalAnchor::Center => position.x - text_width as f64 / 2.0,
386            HorizontalAnchor::Right => position.x - text_width as f64,
387        };
388
389        let vertical_anchor = anchor.get_vertical();
390
391        let y = match (vertical_anchor.get_context(), vertical_anchor.get_value()) {
392            (VerticalAnchorContext::Graphics, VerticalAnchorValue::Bottom) => {
393                position.y - size / 1.25
394            }
395            (VerticalAnchorContext::Math, VerticalAnchorValue::Bottom) => position.y,
396            (_, VerticalAnchorValue::Center) => position.y - size / 1.25 / 2.0,
397            (VerticalAnchorContext::Graphics, VerticalAnchorValue::Top) => position.y,
398            (VerticalAnchorContext::Math, VerticalAnchorValue::Top) => position.y - size / 1.25,
399        };
400
401        for i in -1..=1 {
402            for j in -1..=1 {
403                if i != 0 || j != 0 {
404                    draw_text_mut(
405                        &mut self.image,
406                        srgba_to_rgba8(outline_color),
407                        (x - i as f64 * outline_thickness).round() as i32,
408                        (y - j as f64 * outline_thickness).round() as i32,
409                        size as f32,
410                        &self.font,
411                        text,
412                    );
413                }
414            }
415        }
416
417        draw_text_mut(
418            &mut self.image,
419            srgba_to_rgba8(color),
420            x as i32,
421            y as i32,
422            size as f32,
423            &self.font,
424            text,
425        );
426    }
427
428    fn render_rectangle(
429        &mut self,
430        position: DVec2,
431        width: f64,
432        height: f64,
433        offset: DVec2,
434        rotation: f64,
435        color: Srgba,
436    ) {
437        let position = self.map_dvec2(position);
438        let width = self.map_value(width) - 1.0;
439        let height = self.map_value(height) - 1.0;
440
441        let base_points = self.get_base_points(position, width, height);
442        let offset_vec = self.get_offset_vec(width, height, offset);
443        let offset_points = self.get_offset_points(&base_points, offset_vec);
444        let rotated_points = self.get_rotated_points(&offset_points, position, rotation);
445
446        let integer_points = self
447            .get_unique_integer_points(&rotated_points)
448            .iter()
449            .map(|integer_point| Point::new(integer_point.x, integer_point.y))
450            .collect::<Vec<Point<i32>>>();
451
452        if integer_points.len() == 1 {
453            let integer_point = integer_points.first().unwrap();
454
455            self.render_point(dvec2(integer_point.x as f64, integer_point.y as f64), color);
456        } else {
457            draw_polygon_mut(&mut self.image, &integer_points, srgba_to_rgba8(color));
458        }
459    }
460
461    fn render_rectangle_lines(
462        &mut self,
463        position: DVec2,
464        width: f64,
465        height: f64,
466        offset: DVec2,
467        rotation: f64,
468        thickness: f64,
469        color: Srgba,
470    ) {
471        let position = self.map_dvec2(position);
472        let width = self.map_value(width) - 1.0;
473        let height = self.map_value(height) - 1.0;
474        let thickness = self.map_value(thickness);
475
476        let base_points = self.get_base_points(position, width, height);
477        let offset_vec = self.get_offset_vec(width, height, offset);
478        let offset_points = self.get_offset_points(&base_points, offset_vec);
479        let rotated_points = self.get_rotated_points(&offset_points, position, rotation);
480
481        let integer_points = self
482            .get_unique_integer_points(&rotated_points)
483            .iter()
484            .map(|integer_point| Point::new(integer_point.x, integer_point.y))
485            .collect::<Vec<Point<i32>>>();
486
487        let min_x = integer_points
488            .iter()
489            .map(|integer_point| integer_point.x)
490            .min()
491            .unwrap();
492        let max_x = integer_points
493            .iter()
494            .map(|integer_point| integer_point.x)
495            .max()
496            .unwrap();
497
498        let min_y = integer_points
499            .iter()
500            .map(|integer_point| integer_point.y)
501            .min()
502            .unwrap();
503        let max_y = integer_points
504            .iter()
505            .map(|integer_point| integer_point.y)
506            .max()
507            .unwrap();
508
509        let min_vec = ivec2(min_x, min_y).as_dvec2();
510
511        let renderer_width = max_x - min_x + 1;
512        let renderer_height = max_y - min_y + 1;
513
514        let mut rectangle_renderer = ImageRenderer::new(
515            renderer_width as u32,
516            renderer_height as u32,
517            1.0,
518            DVec2::ZERO,
519            1,
520            self.font.clone(),
521        );
522
523        rectangle_renderer.render_rectangle(
524            position - min_vec,
525            width + 1.0,
526            height + 1.0,
527            offset,
528            rotation,
529            color,
530        );
531
532        let midpoint = rotated_points
533            .iter()
534            .copied()
535            .map(|rotated_point| rotated_point - min_vec)
536            .sum::<DVec2>()
537            / 4.0;
538
539        rectangle_renderer.render_rectangle(
540            midpoint,
541            width + 1.0 - 2.0 * thickness,
542            height + 1.0 - 2.0 * thickness,
543            DVec2::splat(0.5),
544            rotation,
545            Srgba::new(0.0, 0.0, 0.0, 0.0),
546        );
547
548        overlay(
549            &mut self.image,
550            &rectangle_renderer.render_image_onto(rectangle_renderer.transparent()),
551            min_x as i64,
552            min_y as i64,
553        );
554    }
555
556    fn render_equilateral_triangle(
557        &mut self,
558        position: DVec2,
559        radius: f64,
560        rotation: f64,
561        color: Srgba,
562    ) {
563        let position = self.map_dvec2(position);
564        let radius = self.map_value(radius);
565
566        let points = (0..3)
567            .map(|i| position + radius * DVec2::from_angle(i as f64 * 2.0 * PI / 3.0 + rotation))
568            .collect::<Vec<DVec2>>();
569
570        let integer_points = self
571            .get_unique_integer_points(&points)
572            .iter()
573            .map(|integer_point| Point::new(integer_point.x, integer_point.y))
574            .collect::<Vec<Point<i32>>>();
575
576        if integer_points.len() == 1 {
577            let integer_point = integer_points.first().unwrap();
578
579            self.render_point(dvec2(integer_point.x as f64, integer_point.y as f64), color);
580        } else {
581            draw_polygon_mut(&mut self.image, &integer_points, srgba_to_rgba8(color));
582        }
583    }
584
585    fn render_equilateral_triangle_lines(
586        &mut self,
587        position: DVec2,
588        radius: f64,
589        rotation: f64,
590        thickness: f64,
591        color: Srgba,
592    ) {
593        let position = self.map_dvec2(position);
594        let radius = self.map_value(radius);
595        let thickness = self.map_value(thickness);
596
597        let points = (0..3)
598            .map(|i| position + radius * DVec2::from_angle(i as f64 * 2.0 * PI / 3.0 + rotation))
599            .collect::<Vec<DVec2>>();
600
601        let integer_points = self
602            .get_unique_integer_points(&points)
603            .iter()
604            .map(|integer_point| Point::new(integer_point.x, integer_point.y))
605            .collect::<Vec<Point<i32>>>();
606
607        let min_x = integer_points
608            .iter()
609            .map(|integer_point| integer_point.x)
610            .min()
611            .expect("triangles have more than 0 points");
612        let max_x = integer_points
613            .iter()
614            .map(|integer_point| integer_point.x)
615            .max()
616            .expect("triangles have more than 0 points");
617        let min_y = integer_points
618            .iter()
619            .map(|integer_point| integer_point.y)
620            .min()
621            .expect("triangles have more than 0 points");
622        let max_y = integer_points
623            .iter()
624            .map(|integer_point| integer_point.y)
625            .max()
626            .expect("triangles have more than 0 points");
627
628        let min_point = ivec2(min_x, min_y);
629
630        let renderer_width = (max_x - min_x + 1) as u32;
631        let renderer_height = (max_y - min_y + 1) as u32;
632
633        let mut triangle_renderer = ImageRenderer::new(
634            renderer_width,
635            renderer_height,
636            1.0,
637            DVec2::ZERO,
638            1,
639            self.font.clone(),
640        );
641
642        triangle_renderer.render_equilateral_triangle(
643            (position - min_point.as_dvec2()).round(),
644            radius,
645            rotation,
646            color,
647        );
648
649        triangle_renderer.render_equilateral_triangle(
650            (position - min_point.as_dvec2()).round(),
651            radius - thickness,
652            rotation,
653            Srgba::new(0.0, 0.0, 0.0, 0.0),
654        );
655
656        overlay(
657            &mut self.image,
658            &triangle_renderer.render_image_onto(triangle_renderer.transparent()),
659            min_x as i64,
660            min_y as i64,
661        );
662    }
663}
664
665fn rotate_point_around(point: DVec2, axis: DVec2, theta: f64) -> DVec2 {
666    if theta == 0.0 {
667        return point;
668    }
669
670    let relative = point - axis;
671    let relative_theta = relative.to_angle();
672    let new_relative_theta = relative_theta + theta;
673    let new_relative = DVec2::from_angle(new_relative_theta) * relative.length();
674    new_relative + axis
675}