| use egui::{pos2, Pos2, Rect, Vec2}; |
| |
| pub trait ScreenBounds { |
| fn zoom_point(&mut self, center: Pos2, zoom_factor: f32); |
| fn calc_scale(&self, screen_bounds: Rect) -> f32; |
| fn translate(&mut self, delta: Vec2); |
| fn screen_pos_to_world(&self, screen_point: Pos2, screen_bounds: Rect) -> Pos2; |
| fn world_pos_to_screen(&self, world_point: Pos2, screen_bounds: Rect) -> Pos2; |
| |
| fn screen_rect_to_world(&self, screen_rect: Rect, screen_bounds: Rect) -> Rect; |
| fn world_rect_to_screen(&self, world_rect: Rect, screen_bounds: Rect) -> Rect; |
| } |
| |
| impl ScreenBounds for Rect { |
| fn zoom_point(&mut self, center: Pos2, zoom_factor: f32) { |
| let mut left = center.x - self.left(); |
| let mut right = self.right() - center.x; |
| left *= zoom_factor; |
| right *= zoom_factor; |
| let mut top = center.y - self.top(); |
| let mut bottom = self.bottom() - center.y; |
| top *= zoom_factor; |
| bottom *= zoom_factor; |
| |
| self.set_left(center.x - left); |
| self.set_right(center.x + right); |
| self.set_top(center.y - top); |
| self.set_bottom(center.y + bottom); |
| } |
| |
| fn calc_scale(&self, screen_bounds: Rect) -> f32 { |
| let x_scale = screen_bounds.width() / (self.right() - self.left()); |
| let y_scale = screen_bounds.height() / (self.bottom() - self.top()); |
| x_scale.min(y_scale) |
| } |
| |
| fn translate(&mut self, delta: Vec2) { |
| self.set_left(self.left() - delta.x); |
| self.set_right(self.right() - delta.x); |
| self.set_top(self.top() - delta.y); |
| self.set_bottom(self.bottom() - delta.y); |
| } |
| |
| fn screen_pos_to_world(&self, screen_point: Pos2, screen_bounds: Rect) -> Pos2 { |
| let scale = self.calc_scale(screen_bounds); |
| let world_x = (screen_point.x - screen_bounds.left()) / scale + self.left(); |
| let world_y = (screen_point.y - screen_bounds.top()) / scale + self.top(); |
| pos2(world_x, world_y) |
| } |
| |
| fn world_pos_to_screen(&self, world_point: Pos2, screen_bounds: Rect) -> Pos2 { |
| let scale = self.calc_scale(screen_bounds); |
| let screen_x = (world_point.x - self.left()) * scale + screen_bounds.left(); |
| let screen_y = (world_point.y - self.top()) * scale + screen_bounds.top(); |
| pos2(screen_x, screen_y) |
| } |
| |
| fn screen_rect_to_world(&self, screen_rect: Rect, screen_bounds: Rect) -> Rect { |
| let left_top = self.screen_pos_to_world(screen_rect.left_top(), screen_bounds); |
| let right_bottom = self.screen_pos_to_world(screen_rect.right_bottom(), screen_bounds); |
| Rect::from_min_max(left_top, right_bottom) |
| } |
| |
| fn world_rect_to_screen(&self, world_rect: Rect, screen_bounds: Rect) -> Rect { |
| let left_top = self.world_pos_to_screen(world_rect.left_top(), screen_bounds); |
| let right_bottom = self.world_pos_to_screen(world_rect.right_bottom(), screen_bounds); |
| Rect::from_min_max(left_top, right_bottom) |
| } |
| } |
