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Diffstat (limited to 'src/drawing/rasterizer/polygon.rs')
| -rw-r--r-- | src/drawing/rasterizer/polygon.rs | 245 |
1 files changed, 0 insertions, 245 deletions
diff --git a/src/drawing/rasterizer/polygon.rs b/src/drawing/rasterizer/polygon.rs deleted file mode 100644 index 169b83a..0000000 --- a/src/drawing/rasterizer/polygon.rs +++ /dev/null @@ -1,245 +0,0 @@ -use crate::drawing::backend::{BackendCoord, BackendStyle, DrawingErrorKind}; -use crate::drawing::DrawingBackend; - -use crate::style::Color; - -use std::cmp::{Ord, Ordering, PartialOrd}; - -#[derive(Clone, Debug)] -struct Edge { - epoch: u32, - total_epoch: u32, - slave_begin: i32, - slave_end: i32, -} - -impl Edge { - fn horizontal_sweep(mut from: BackendCoord, mut to: BackendCoord) -> Option<Edge> { - if from.0 == to.0 { - return None; - } - - if from.0 > to.0 { - std::mem::swap(&mut from, &mut to); - } - - Some(Edge { - epoch: 0, - total_epoch: (to.0 - from.0) as u32, - slave_begin: from.1, - slave_end: to.1, - }) - } - - fn vertical_sweep(from: BackendCoord, to: BackendCoord) -> Option<Edge> { - Edge::horizontal_sweep((from.1, from.0), (to.1, to.0)) - } - - fn get_master_pos(&self) -> i32 { - (self.total_epoch - self.epoch) as i32 - } - - fn inc_epoch(&mut self) { - self.epoch += 1; - } - - fn get_slave_pos(&self) -> f64 { - f64::from(self.slave_begin) - + (i64::from(self.slave_end - self.slave_begin) * i64::from(self.epoch)) as f64 - / f64::from(self.total_epoch) - } -} - -impl PartialOrd for Edge { - fn partial_cmp(&self, other: &Self) -> Option<Ordering> { - self.get_slave_pos().partial_cmp(&other.get_slave_pos()) - } -} - -impl PartialEq for Edge { - fn eq(&self, other: &Self) -> bool { - self.get_slave_pos() == other.get_slave_pos() - } -} - -impl Eq for Edge {} - -impl Ord for Edge { - fn cmp(&self, other: &Self) -> Ordering { - self.get_slave_pos() - .partial_cmp(&other.get_slave_pos()) - .unwrap() - } -} - -pub fn fill_polygon<DB: DrawingBackend, S: BackendStyle>( - back: &mut DB, - vertices: &[BackendCoord], - style: &S, -) -> Result<(), DrawingErrorKind<DB::ErrorType>> { - if let Some((x_span, y_span)) = - vertices - .iter() - .fold(None, |res: Option<((i32, i32), (i32, i32))>, (x, y)| { - Some( - res.map(|((min_x, max_x), (min_y, max_y))| { - ( - (min_x.min(*x), max_x.max(*x)), - (min_y.min(*y), max_y.max(*y)), - ) - }) - .unwrap_or(((*x, *x), (*y, *y))), - ) - }) - { - // First of all, let's handle the case that all the points is in a same vertical or - // horizontal line - if x_span.0 == x_span.1 || y_span.0 == y_span.1 { - return back.draw_line((x_span.0, y_span.0), (x_span.1, y_span.1), style); - } - - let horizontal_sweep = x_span.1 - x_span.0 > y_span.1 - y_span.0; - - let mut edges: Vec<_> = vertices - .iter() - .zip(vertices.iter().skip(1)) - .map(|(a, b)| (*a, *b)) - .collect(); - edges.push((vertices[vertices.len() - 1], vertices[0])); - edges.sort_by_key(|((x1, y1), (x2, y2))| { - if horizontal_sweep { - *x1.min(x2) - } else { - *y1.min(y2) - } - }); - - for edge in &mut edges.iter_mut() { - if horizontal_sweep { - if (edge.0).0 > (edge.1).0 { - std::mem::swap(&mut edge.0, &mut edge.1); - } - } else if (edge.0).1 > (edge.1).1 { - std::mem::swap(&mut edge.0, &mut edge.1); - } - } - - let (low, high) = if horizontal_sweep { x_span } else { y_span }; - - let mut idx = 0; - - let mut active_edge: Vec<Edge> = vec![]; - - for sweep_line in low..=high { - let mut new_vec = vec![]; - - for mut e in active_edge { - if e.get_master_pos() > 0 { - e.inc_epoch(); - new_vec.push(e); - } - } - - active_edge = new_vec; - - loop { - if idx >= edges.len() { - break; - } - let line = if horizontal_sweep { - (edges[idx].0).0 - } else { - (edges[idx].0).1 - }; - if line > sweep_line { - break; - } - - let edge_obj = if horizontal_sweep { - Edge::horizontal_sweep(edges[idx].0, edges[idx].1) - } else { - Edge::vertical_sweep(edges[idx].0, edges[idx].1) - }; - - if let Some(edge_obj) = edge_obj { - active_edge.push(edge_obj); - } - - idx += 1; - } - - active_edge.sort(); - - let mut first = None; - let mut second = None; - - for edge in active_edge.iter() { - if first.is_none() { - first = Some(edge.clone()) - } else if second.is_none() { - second = Some(edge.clone()) - } - - if let Some(a) = first.clone() { - if let Some(b) = second.clone() { - if a.get_master_pos() == 0 && b.get_master_pos() != 0 { - first = Some(b); - second = None; - continue; - } - - if a.get_master_pos() != 0 && b.get_master_pos() == 0 { - first = Some(a); - second = None; - continue; - } - - let from = a.get_slave_pos(); - let to = b.get_slave_pos(); - - if a.get_master_pos() == 0 && b.get_master_pos() == 0 && to - from > 1.0 { - first = None; - second = None; - continue; - } - - if horizontal_sweep { - check_result!(back.draw_line( - (sweep_line, from.ceil() as i32), - (sweep_line, to.floor() as i32), - &style.as_color(), - )); - check_result!(back.draw_pixel( - (sweep_line, from.floor() as i32), - &style.as_color().mix(from.ceil() - from), - )); - check_result!(back.draw_pixel( - (sweep_line, to.ceil() as i32), - &style.as_color().mix(to - to.floor()), - )); - } else { - check_result!(back.draw_line( - (from.ceil() as i32, sweep_line), - (to.floor() as i32, sweep_line), - &style.as_color(), - )); - check_result!(back.draw_pixel( - (from.floor() as i32, sweep_line), - &style.as_color().mix(from.ceil() - from), - )); - check_result!(back.draw_pixel( - (to.ceil() as i32, sweep_line), - &style.as_color().mix(to.floor() - to), - )); - } - - first = None; - second = None; - } - } - } - } - } - - Ok(()) -} |