Merge pull request #6077 from penpot/elenatorro-10516-fix-shadow-rendering

🐛 Fix drop shadows viewport clipping

render-wasm/src/render.rs

@@ -183,6 +183,9 @@ impl RenderState {
 
     pub fn reset_canvas(&mut self) {
         self.surfaces.canvas(SurfaceId::Fills).restore_to_count(1);
+        self.surfaces
+            .canvas(SurfaceId::DropShadows)
+            .restore_to_count(1);
         self.surfaces.canvas(SurfaceId::Strokes).restore_to_count(1);
         self.surfaces.canvas(SurfaceId::Current).restore_to_count(1);
 
@@ -191,6 +194,7 @@ impl RenderState {
                 SurfaceId::Fills,
                 SurfaceId::Strokes,
                 SurfaceId::Current,
+                SurfaceId::DropShadows,
                 SurfaceId::Shadow,
                 SurfaceId::Overlay,
             ],
@@ -216,6 +220,16 @@ impl RenderState {
     pub fn apply_drawing_to_render_canvas(&mut self, shape: &Shape) {
         self.surfaces
             .flush_and_submit(&mut self.gpu_state, SurfaceId::Fills);
+
+        self.surfaces
+            .flush_and_submit(&mut self.gpu_state, SurfaceId::DropShadows);
+
+        self.surfaces.draw_into(
+            SurfaceId::DropShadows,
+            SurfaceId::Current,
+            Some(&skia::Paint::default()),
+        );
+
         self.surfaces.draw_into(
             SurfaceId::Fills,
             SurfaceId::Current,
@@ -259,6 +273,7 @@ impl RenderState {
         self.surfaces.apply_mut(
             &[
                 SurfaceId::Shadow,
+                SurfaceId::DropShadows,
                 SurfaceId::Overlay,
                 SurfaceId::Fills,
                 SurfaceId::Strokes,
@@ -281,17 +296,19 @@ impl RenderState {
         modifiers: Option<&Matrix>,
         clip_bounds: Option<(Rect, Option<Corners>, Matrix)>,
     ) {
-        let surface_ids = &[SurfaceId::Fills, SurfaceId::Strokes];
+        let surface_ids = &[SurfaceId::Fills, SurfaceId::Strokes, SurfaceId::DropShadows];
         self.surfaces.apply_mut(surface_ids, |s| {
             s.canvas().save();
         });
 
         // set clipping
         if let Some((bounds, corners, transform)) = clip_bounds {
-            self.surfaces
-                .apply_mut(&[SurfaceId::Fills, SurfaceId::Strokes], |s| {
+            self.surfaces.apply_mut(
+                &[SurfaceId::Fills, SurfaceId::Strokes, SurfaceId::DropShadows],
+                |s| {
                     s.canvas().concat(&transform);
-                });
+                },
+            );
 
             if let Some(corners) = corners {
                 let rrect = RRect::new_rect_radii(bounds, &corners);
@@ -358,10 +375,12 @@ impl RenderState {
                 text::render(self, text_content);
             }
             _ => {
-                self.surfaces
-                    .apply_mut(&[SurfaceId::Fills, SurfaceId::Strokes], |s| {
+                self.surfaces.apply_mut(
+                    &[SurfaceId::Fills, SurfaceId::Strokes, SurfaceId::DropShadows],
+                    |s| {
                         s.canvas().concat(&matrix);
-                    });
+                    },
+                );
 
                 for fill in shape.fills().rev() {
                     fills::render(self, &shape, fill);
@@ -380,21 +399,17 @@ impl RenderState {
                     );
                 }
 
-                for shadow in shape.drop_shadows().rev().filter(|s| !s.hidden()) {
-                    shadows::render_drop_shadow(
-                        self,
-                        shadow,
-                        self.viewbox.zoom * self.options.dpr(),
-                    );
-                }
+                shadows::render_drop_shadows(self, &shape);
             }
         };
 
         self.apply_drawing_to_render_canvas(&shape);
-        self.surfaces
-            .apply_mut(&[SurfaceId::Fills, SurfaceId::Strokes], |s| {
+        self.surfaces.apply_mut(
+            &[SurfaceId::Fills, SurfaceId::Strokes, SurfaceId::DropShadows],
+            |s| {
                 s.canvas().restore();
-            });
+            },
+        );
     }
 
     pub fn start_render_loop(
@@ -403,22 +418,23 @@ impl RenderState {
         modifiers: &HashMap<Uuid, Matrix>,
         timestamp: i32,
     ) -> Result<(), String> {
-        let surface_ids = &[SurfaceId::Fills, SurfaceId::Strokes];
-
         if self.render_in_progress {
             if let Some(frame_id) = self.render_request_id {
                 self.cancel_animation_frame(frame_id);
             }
         }
         self.reset_canvas();
-        self.surfaces.apply_mut(surface_ids, |s| {
-            s.canvas().scale((
-                self.viewbox.zoom * self.options.dpr(),
-                self.viewbox.zoom * self.options.dpr(),
-            ));
-            s.canvas()
-                .translate((self.viewbox.pan_x, self.viewbox.pan_y));
-        });
+        self.surfaces.apply_mut(
+            &[SurfaceId::Fills, SurfaceId::Strokes, SurfaceId::DropShadows],
+            |s| {
+                s.canvas().scale((
+                    self.viewbox.zoom * self.options.dpr(),
+                    self.viewbox.zoom * self.options.dpr(),
+                ));
+                s.canvas()
+                    .translate((self.viewbox.pan_x, self.viewbox.pan_y));
+            },
+        );
 
         self.pending_nodes = vec![NodeRenderState {
             id: Uuid::nil(),
@@ -510,6 +526,7 @@ impl RenderState {
         self.surfaces.canvas(SurfaceId::Target).save();
         self.surfaces.canvas(SurfaceId::Fills).save();
         self.surfaces.canvas(SurfaceId::Strokes).save();
+        self.surfaces.canvas(SurfaceId::DropShadows).save();
 
         let navigate_zoom = self.viewbox.zoom / cached.viewbox.zoom;
         let navigate_x = cached.viewbox.zoom * (self.viewbox.pan_x - cached.viewbox.pan_x);
@@ -532,6 +549,7 @@ impl RenderState {
         self.surfaces.canvas(SurfaceId::Target).restore();
         self.surfaces.canvas(SurfaceId::Fills).restore();
         self.surfaces.canvas(SurfaceId::Strokes).restore();
+        self.surfaces.canvas(SurfaceId::DropShadows).restore();
 
         self.flush();
 

render-wasm/src/render/fills.rs

@@ -1,14 +1,14 @@
-use skia_safe::{self as skia, RRect};
+use skia_safe::{self as skia, Paint, RRect};
 
 use super::{RenderState, SurfaceId};
 use crate::math::Rect as MathRect;
 use crate::shapes::{Fill, Frame, ImageFill, Rect, Shape, Type};
 
-fn draw_image_fill_in_container(
+fn draw_image_fill(
     render_state: &mut RenderState,
     shape: &Shape,
-    fill: &Fill,
     image_fill: &ImageFill,
+    paint: &Paint,
 ) {
     let image = render_state.images.get(&image_fill.id());
     if image.is_none() {
@@ -19,7 +19,6 @@ fn draw_image_fill_in_container(
     let canvas = render_state.surfaces.canvas(SurfaceId::Fills);
     let container = &shape.selrect;
     let path_transform = shape.to_path_transform();
-    let paint = fill.to_paint(container);
 
     let width = size.0 as f32;
     let height = size.1 as f32;
@@ -110,39 +109,29 @@ fn draw_image_fill_in_container(
  * This SHOULD be the only public function in this module.
  */
 pub fn render(render_state: &mut RenderState, shape: &Shape, fill: &Fill) {
-    let canvas = render_state.surfaces.canvas(SurfaceId::Fills);
-    let selrect = shape.selrect;
-    let path_transform = shape.to_path_transform();
+    let paint = &fill.to_paint(&shape.selrect);
 
     match (fill, &shape.shape_type) {
         (Fill::Image(image_fill), _) => {
-            draw_image_fill_in_container(render_state, shape, fill, image_fill);
+            draw_image_fill(render_state, shape, image_fill, paint);
         }
         (_, Type::Rect(_) | Type::Frame(_)) => {
-            if let Some(corners) = shape.shape_type.corners() {
-                let rrect = RRect::new_rect_radii(selrect, &corners);
-                canvas.draw_rrect(rrect, &fill.to_paint(&selrect));
-            } else {
-                canvas.draw_rect(selrect, &fill.to_paint(&selrect));
-            }
+            render_state
+                .surfaces
+                .draw_rect_to(SurfaceId::Fills, shape, paint);
         }
         (_, Type::Circle) => {
-            canvas.draw_oval(selrect, &fill.to_paint(&selrect));
+            render_state
+                .surfaces
+                .draw_circle_to(SurfaceId::Fills, shape, paint);
         }
         (_, Type::Path(_)) | (_, Type::Bool(_)) => {
-            if let Some(path) = &shape.shape_type.path() {
-                let svg_attrs = &shape.svg_attrs;
-                let mut skia_path = &mut path.to_skia_path();
-
-                if let Some(path_transform) = path_transform {
-                    skia_path = skia_path.transform(&path_transform);
-                    if let Some("evenodd") = svg_attrs.get("fill-rule").map(String::as_str) {
-                        skia_path.set_fill_type(skia::PathFillType::EvenOdd);
-                    }
-                    canvas.draw_path(&skia_path, &fill.to_paint(&selrect));
-                }
-            }
+            render_state
+                .surfaces
+                .draw_path_to(SurfaceId::Fills, shape, paint);
+        }
+        (_, _) => {
+            unreachable!("This shape should not have fills")
         }
-        (_, _) => unreachable!("This shape should not have fills"),
     }
 }

render-wasm/src/render/shadows.rs

@@ -1,17 +1,50 @@
 use skia_safe::{self as skia};
 
 use super::{RenderState, SurfaceId};
-use crate::shapes::Shadow;
+use crate::shapes::{Shadow, Shape, Type};
 
-pub fn render_drop_shadow(render_state: &mut RenderState, shadow: &Shadow, scale: f32) {
-    let shadow_paint = shadow.to_paint(scale);
-    render_state
-        .surfaces
-        .draw_into(SurfaceId::Fills, SurfaceId::Shadow, Some(&shadow_paint));
+pub fn render_drop_shadows(render_state: &mut RenderState, shape: &Shape) {
+    if shape.fills().len() > 0 {
+        for shadow in shape.drop_shadows().rev().filter(|s| !s.hidden()) {
+            render_fill_drop_shadow(render_state, &shape, &shadow);
+        }
+    } else {
+        let scale = render_state.viewbox.zoom * render_state.options.dpr();
+        for shadow in shape.drop_shadows().rev().filter(|s| !s.hidden()) {
+            render_stroke_drop_shadow(render_state, &shadow, scale);
+        }
+    }
+}
+
+fn render_fill_drop_shadow(render_state: &mut RenderState, shape: &Shape, shadow: &Shadow) {
+    let paint = &shadow.get_drop_shadow_paint();
+
+    match &shape.shape_type {
+        Type::Rect(_) | Type::Frame(_) => {
+            render_state
+                .surfaces
+                .draw_rect_to(SurfaceId::DropShadows, shape, paint);
+        }
+        Type::Circle => {
+            render_state
+                .surfaces
+                .draw_circle_to(SurfaceId::DropShadows, shape, paint);
+        }
+        Type::Path(_) | Type::Bool(_) => {
+            render_state
+                .surfaces
+                .draw_path_to(SurfaceId::DropShadows, shape, paint);
+        }
+        _ => {}
+    }
+}
+
+fn render_stroke_drop_shadow(render_state: &mut RenderState, shadow: &Shadow, scale: f32) {
+    let shadow_paint = &shadow.to_paint(scale);
 
     render_state
         .surfaces
-        .draw_into(SurfaceId::Strokes, SurfaceId::Shadow, Some(&shadow_paint));
+        .draw_into(SurfaceId::Strokes, SurfaceId::Shadow, Some(shadow_paint));
 
     render_state.surfaces.draw_into(
         SurfaceId::Shadow,

render-wasm/src/render/surfaces.rs

@@ -1,5 +1,6 @@
 use super::gpu_state::GpuState;
-use skia_safe as skia;
+use crate::shapes::Shape;
+use skia_safe::{self as skia, Paint, RRect};
 
 #[derive(Debug, PartialEq, Clone, Copy)]
 pub enum SurfaceId {
@@ -8,6 +9,7 @@ pub enum SurfaceId {
     Fills,
     Strokes,
     Shadow,
+    DropShadows,
     Overlay,
     Debug,
 }
@@ -23,6 +25,8 @@ pub struct Surfaces {
     shape_strokes: skia::Surface,
     // used for rendering shadows
     shadow: skia::Surface,
+    // used for new shadow rendering
+    drop_shadows: skia::Surface,
     // for drawing the things that are over shadows.
     overlay: skia::Surface,
     // for drawing debug info.
@@ -40,6 +44,7 @@ impl Surfaces {
         let mut target = gpu_state.create_target_surface(width, height);
         let current = target.new_surface_with_dimensions((width, height)).unwrap();
         let shadow = target.new_surface_with_dimensions((width, height)).unwrap();
+        let drop_shadows = target.new_surface_with_dimensions((width, height)).unwrap();
         let overlay = target.new_surface_with_dimensions((width, height)).unwrap();
         let shape_fills = target.new_surface_with_dimensions((width, height)).unwrap();
         let shape_strokes = target.new_surface_with_dimensions((width, height)).unwrap();
@@ -49,6 +54,7 @@ impl Surfaces {
             target,
             current,
             shadow,
+            drop_shadows,
             overlay,
             shape_fills,
             shape_strokes,
@@ -94,6 +100,7 @@ impl Surfaces {
             SurfaceId::Target => &mut self.target,
             SurfaceId::Current => &mut self.current,
             SurfaceId::Shadow => &mut self.shadow,
+            SurfaceId::DropShadows => &mut self.drop_shadows,
             SurfaceId::Overlay => &mut self.overlay,
             SurfaceId::Fills => &mut self.shape_fills,
             SurfaceId::Strokes => &mut self.shape_strokes,
@@ -107,7 +114,27 @@ impl Surfaces {
         self.current = self.target.new_surface_with_dimensions(dim).unwrap();
         self.overlay = self.target.new_surface_with_dimensions(dim).unwrap();
         self.shadow = self.target.new_surface_with_dimensions(dim).unwrap();
+        self.drop_shadows = self.target.new_surface_with_dimensions(dim).unwrap();
         self.shape_fills = self.target.new_surface_with_dimensions(dim).unwrap();
         self.debug = self.target.new_surface_with_dimensions(dim).unwrap();
     }
+
+    pub fn draw_rect_to(&mut self, id: SurfaceId, shape: &Shape, paint: &Paint) {
+        if let Some(corners) = shape.shape_type.corners() {
+            let rrect = RRect::new_rect_radii(shape.selrect, &corners);
+            self.canvas(id).draw_rrect(rrect, paint);
+        } else {
+            self.canvas(id).draw_rect(shape.selrect, paint);
+        }
+    }
+
+    pub fn draw_circle_to(&mut self, id: SurfaceId, shape: &Shape, paint: &Paint) {
+        self.canvas(id).draw_oval(shape.selrect, paint);
+    }
+
+    pub fn draw_path_to(&mut self, id: SurfaceId, shape: &Shape, paint: &Paint) {
+        if let Some(path) = shape.get_skia_path() {
+            self.canvas(id).draw_path(&path, paint);
+        }
+    }
 }

render-wasm/src/shapes.rs

@@ -646,6 +646,21 @@ impl Shape {
         }
     }
 
+    pub fn get_skia_path(&self) -> Option<skia::Path> {
+        if let Some(path) = self.shape_type.path() {
+            let mut skia_path = path.to_skia_path();
+            if let Some(path_transform) = self.to_path_transform() {
+                skia_path.transform(&path_transform);
+            }
+            if let Some("evenodd") = self.svg_attrs.get("fill-rule").map(String::as_str) {
+                skia_path.set_fill_type(skia::PathFillType::EvenOdd);
+            }
+            Some(skia_path)
+        } else {
+            None
+        }
+    }
+
     fn transform_selrect(&mut self, transform: &Matrix) {
         let mut center = self.selrect.center();
         center = transform.map_point(center);

render-wasm/src/shapes/shadows.rs

@@ -123,4 +123,33 @@ impl Shadow {
 
         filter
     }
+
+    // New methods for DropShadow
+    pub fn get_drop_shadow_paint(&self) -> skia::Paint {
+        let mut paint = skia::Paint::default();
+
+        let image_filter = self.get_drop_shadow_filter();
+
+        paint.set_image_filter(image_filter);
+        paint.set_anti_alias(true);
+
+        paint
+    }
+
+    fn get_drop_shadow_filter(&self) -> Option<ImageFilter> {
+        let mut filter = image_filters::drop_shadow_only(
+            (self.offset.0, self.offset.1),
+            (self.blur, self.blur),
+            self.color,
+            None,
+            None,
+            None,
+        );
+
+        if self.spread > 0. {
+            filter = image_filters::dilate((self.spread, self.spread), filter, None);
+        }
+
+        filter
+    }
 }