1 files changed, 86 insertions, 0 deletions

diff --git a/core/src/rendering.rs b/core/src/rendering.rs
new file mode 100644
index 0000000..f7a0189
--- /dev/null
+++ b/core/src/rendering.rs
@@ -0,0 +1,86 @@
+use super::core_shapes::*;
+use super::styles::{DefinedDashStyle, DefinedStrokeStyle, FillStyle, Pattern};
+use super::text::{DefinedFontDescription, FontDescription};
+use super::types::DefinedShapeContext;
+
+pub trait Renderer {
+    fn move_to(&mut self, x: f64, y: f64);
+    fn stroke(&mut self);
+    fn fill(&mut self);
+    fn fill_preserve(&mut self);
+    fn set_pattern(&mut self, pattern: &Pattern);
+    fn set_dash(&mut self, dash: &DefinedDashStyle);
+    fn clear_dash(&mut self);
+    fn set_line_width(&mut self, width: f64);
+    fn line_to(&mut self, x: f64, y: f64);
+    fn rectangle(&mut self, x: f64, y: f64, width: f64, height: f64);
+    // For a font of size 1.
+    fn text_extents(&self, text: &str, font: &FontDescription) -> (f64, f64);
+    fn show_text(&mut self, text: &str, font: &DefinedFontDescription);
+}
+
+pub trait Render {
+    fn render(&self, context: DefinedShapeContext, renderer: &mut dyn Renderer);
+}
+
+fn draw(fill: &FillStyle, stroke: &DefinedStrokeStyle, renderer: &mut dyn Renderer) {
+    let stroking = !stroke.pattern.is_none();
+
+    if !fill.pattern.is_none() {
+        renderer.set_pattern(&fill.pattern);
+        if stroking {
+            renderer.fill_preserve();
+        } else {
+            renderer.fill();
+        }
+    }
+
+    if !stroke.pattern.is_none() {
+        renderer.set_pattern(&stroke.pattern);
+        renderer.set_line_width(stroke.line_width);
+        if let Some(dash) = &stroke.dash {
+            renderer.set_dash(dash);
+        }
+        renderer.stroke();
+        renderer.clear_dash();
+    }
+}
+
+impl Render for Rectangle {
+    fn render(&self, context: DefinedShapeContext, renderer: &mut dyn Renderer) {
+        let bounds = &context.bounds;
+        renderer.rectangle(bounds.left, bounds.top, bounds.width, bounds.height);
+        draw(&context.fill, &context.stroke, renderer);
+    }
+}
+
+impl Render for DefinedText {
+    fn render(&self, context: DefinedShapeContext, renderer: &mut dyn Renderer) {
+        // TODO: select font, style, text shaping (renderer specific), etc.
+        let bounds = &context.bounds;
+        //renderer.move_to(bounds.left, bounds.top + self.font.size);
+        renderer.move_to(bounds.left, bounds.top);
+        // TODO: ???
+        //draw(&context.fill, &context.stroke, renderer);
+        renderer.show_text(&self.content, &self.font);
+    }
+}
+
+impl Render for DefinedStraightPath {
+    fn render(&self, context: DefinedShapeContext, renderer: &mut dyn Renderer) {
+        let mut iter = self.points.iter();
+
+        let first_point = match iter.next() {
+            Some(point) => point,
+            None => return,
+        };
+
+        renderer.move_to(first_point.x, first_point.y);
+
+        for point in iter {
+            renderer.line_to(point.x, point.y);
+        }
+
+        draw(&context.fill, &context.stroke, renderer);
+    }
+}