fix crash on export if a chamber or dungeon is empty

src/common.rs

@@ -167,6 +167,15 @@ impl BitAndAssign<BBox> for BBox {
     }
 }
 
+impl BBox {
+    pub fn is_valid(&self) -> bool {
+        self.min.x.is_finite()
+            && self.min.y.is_finite()
+            && self.max.x.is_finite()
+            && self.max.y.is_finite()
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::{BBox, Vec2};
@@ -206,4 +215,28 @@ mod tests {
         assert_eq!(a.max.x, 6.0);
         assert_eq!(a.max.y, 7.0);
     }
+
+    #[test]
+    fn test_invalid_bbox() {
+        let a = BBox {
+            min: Vec2 {
+                x: 1.0 / 0.0,
+                y: 1.0 / 0.0,
+            },
+            max: Vec2 {
+                x: 1.0 / 0.0,
+                y: 1.0 / 0.0,
+            },
+        };
+        assert_eq!(a.is_valid(), false)
+    }
+
+    #[test]
+    fn test_valid_bbox() {
+        let a = BBox {
+            min: Vec2 { x: 1.0, y: 1.0 },
+            max: Vec2 { x: 1.0, y: 1.0 },
+        };
+        assert_eq!(a.is_valid(), true)
+    }
 }

src/export.rs

@@ -226,6 +226,10 @@ fn prims_to_bbox(prims: &Vec<Box<dyn Primitive>>) -> BBox {
 fn draw_full_dungeon(dungeon: &Dungeon, ctx: &Context, include_hidden: bool) {
     let all_prims = dungeon_to_primitives(dungeon, include_hidden);
     let bbox = prims_to_bbox(&all_prims);
+    // early abort on empty dungeon
+    if !bbox.is_valid() {
+        return;
+    }
 
     let mut cur_h = START_H;
     let (_, tl) = layout_title();
@@ -355,41 +359,43 @@ fn chamber_headline(chamber: &Chamber) -> PdfElement {
                 bbox.min = bbox.min - Vec2 { x: 50.0, y: 50.0 };
                 bbox.max = bbox.max + Vec2 { x: 50.0, y: 50.0 };
 
-                let size = bbox.max - bbox.min;
-                let scale = IMAGE_SIZE / f64::max(size.x, size.y);
-                ctx.translate(
-                    -bbox.min.x * scale + LEFT_SPACE,
-                    -bbox.min.y * scale + cur_h,
-                );
-                ctx.scale(scale, scale);
-
-                let mut grid = Grid::new();
-                grid.color = Rgb {
-                    r: 0.5,
-                    g: 0.5,
-                    b: 0.5,
-                };
-                grid.width = 1.0;
-
-                // set clipping
-                ctx.rectangle(bbox.min.x, bbox.min.y, size.x, size.y);
-                ctx.clip();
-                ctx.new_path();
-
-                // draw grid
-                ctx.set_dash(&vec![10.0, 10.0], 0.0);
-                for prim in grid.draw(bbox.min.into(), bbox.max.into()) {
-                    prim.draw(&ctx)
+                if bbox.is_valid() {
+                    let size = bbox.max - bbox.min;
+                    let scale = IMAGE_SIZE / f64::max(size.x, size.y);
+                    ctx.translate(
+                        -bbox.min.x * scale + LEFT_SPACE,
+                        -bbox.min.y * scale + cur_h,
+                    );
+                    ctx.scale(scale, scale);
+
+                    let mut grid = Grid::new();
+                    grid.color = Rgb {
+                        r: 0.5,
+                        g: 0.5,
+                        b: 0.5,
+                    };
+                    grid.width = 1.0;
+
+                    // set clipping
+                    ctx.rectangle(bbox.min.x, bbox.min.y, size.x, size.y);
+                    ctx.clip();
+                    ctx.new_path();
+
+                    // draw grid
+                    ctx.set_dash(&vec![10.0, 10.0], 0.0);
+                    for prim in grid.draw(bbox.min.into(), bbox.max.into()) {
+                        prim.draw(&ctx)
+                    }
+                    ctx.set_dash(&vec![], 0.0);
+
+                    // draw chamber
+                    for prim in prims.iter() {
+                        prim.draw(&ctx)
+                    }
+
+                    ctx.reset_clip();
+                    ctx.identity_matrix();
                 }
-                ctx.set_dash(&vec![], 0.0);
-
-                // draw chamber
-                for prim in prims.iter() {
-                    prim.draw(&ctx)
-                }
-
-                ctx.reset_clip();
-                ctx.identity_matrix();
             }
         }),
     }
@@ -593,7 +599,14 @@ pub fn to_pdf(dungeon: &Dungeon, path: String) {
 pub fn to_full_player_map_pdf(dungeon: &Dungeon, path: String) {
     // Draw entire dungeon
     let all_prims = dungeon_to_primitives(dungeon, false);
+    // early abort of dungeon is empty (nothing to draw)
+    if all_prims.len() == 0 {
+        return;
+    }
     let bbox = prims_to_bbox(&all_prims);
+    if !bbox.is_valid() {
+        return;
+    }
 
     let size = bbox.max - bbox.min;
     // determine if page should be horizontal or vertical
@@ -657,3 +670,42 @@ pub fn to_full_player_map_pdf(dungeon: &Dungeon, path: String) {
     ctx.identity_matrix();
     ctx.show_page().unwrap();
 }
+
+#[cfg(test)]
+mod test {
+    use crate::{chamber::Chamber, dungeon::Dungeon};
+
+    use super::{to_full_player_map_pdf, to_pdf};
+
+    #[test]
+    fn test_to_full_player_map_pdf_empty() {
+        let dungeon = &Dungeon::new();
+        to_full_player_map_pdf(
+            dungeon,
+            "/tmp/test_to_full_player_map_pdf_empty.pdf".to_string(),
+        )
+    }
+    #[test]
+    fn test_to_full_player_map_pdf_empty_chamber() {
+        let mut dungeon = Dungeon::new();
+        let chamber = Chamber::new();
+        dungeon.add_chamber(chamber);
+        to_full_player_map_pdf(
+            &dungeon,
+            "/tmp/test_to_full_player_map_pdf_empty_chamber.pdf".to_string(),
+        )
+    }
+
+    #[test]
+    fn test_to_pdf_empty() {
+        let dungeon = &Dungeon::new();
+        to_pdf(dungeon, "/tmp/test_to_pdf_empty.pdf".to_string())
+    }
+    #[test]
+    fn test_to_pdf_empty_chamber() {
+        let mut dungeon = Dungeon::new();
+        let chamber = Chamber::new();
+        dungeon.add_chamber(chamber);
+        to_pdf(&dungeon, "/tmp/test_to_pdf_empty_chamber.pdf".to_string())
+    }
+}