added alpha channel

src/widget.rs

@@ -0,0 +1,96 @@
+use tui::{
+    buffer::Buffer,
+    layout::Rect,
+    style::{Color, Modifier},
+    widgets::Widget,
+};
+
+use crate::{
+    style::{convert, RinkColor, RinkStyle},
+    Config,
+};
+
+pub struct RinkBuffer<'a> {
+    buf: &'a mut Buffer,
+    cfg: Config,
+}
+
+impl<'a> RinkBuffer<'a> {
+    fn new(buf: &'a mut Buffer, cfg: Config) -> RinkBuffer<'a> {
+        Self { buf, cfg }
+    }
+
+    pub fn set(&mut self, x: u16, y: u16, new: &RinkCell) {
+        let mut cell = self.buf.get_mut(x, y);
+        cell.bg = convert(self.cfg.rendering_mode, new.bg.blend(cell.bg));
+        if &new.symbol == "" {
+            if &cell.symbol != "" {
+                // allows text to "shine through" transparent backgrounds
+                cell.fg = convert(self.cfg.rendering_mode, new.bg.blend(cell.fg));
+            }
+        } else {
+            cell.modifier = new.modifier;
+            cell.symbol = new.symbol.clone();
+            cell.fg = convert(self.cfg.rendering_mode, new.fg.blend(cell.bg));
+        }
+    }
+}
+
+pub trait RinkWidget {
+    fn render(self, area: Rect, buf: RinkBuffer);
+}
+
+pub struct WidgetWithContext<T: RinkWidget> {
+    widget: T,
+    config: Config,
+}
+
+impl<T: RinkWidget> WidgetWithContext<T> {
+    pub fn new(widget: T, config: Config) -> WidgetWithContext<T> {
+        WidgetWithContext { widget, config }
+    }
+}
+
+impl<T: RinkWidget> Widget for WidgetWithContext<T> {
+    fn render(self, area: Rect, buf: &mut Buffer) {
+        self.widget.render(area, RinkBuffer::new(buf, self.config))
+    }
+}
+
+#[derive(Clone)]
+pub struct RinkCell {
+    pub symbol: String,
+    pub bg: RinkColor,
+    pub fg: RinkColor,
+    pub modifier: Modifier,
+}
+
+impl Default for RinkCell {
+    fn default() -> Self {
+        Self {
+            symbol: "".to_string(),
+            fg: RinkColor {
+                color: Color::Rgb(0, 0, 0),
+                alpha: 0.0,
+            },
+            bg: RinkColor {
+                color: Color::Rgb(0, 0, 0),
+                alpha: 0.0,
+            },
+            modifier: Modifier::empty(),
+        }
+    }
+}
+
+impl RinkCell {
+    pub fn set_style(&mut self, style: RinkStyle) {
+        if let Some(c) = style.fg {
+            self.fg = c;
+        }
+        if let Some(c) = style.bg {
+            self.bg = c;
+        }
+        self.modifier = style.add_modifier;
+        self.modifier.remove(style.sub_modifier);
+    }
+}