Screen trait

src/writers/mod.rs

@@ -46,14 +46,18 @@ static BLANK_CHARACTER: ScreenCharacter = ScreenCharacter {
     color: TextModeColor::new(Color16Bit::Yellow, Color16Bit::Black),
 };
 
-/// A helper trait used to interact with various vga text modes.
-pub trait TextWriter {
-    /// Returns the width of the `TextWriter`.
+/// A helper trait used to interact with various vga screens.
+pub trait Screen {
+    /// Returns the width of the `Screen`.
     fn get_width(&self) -> usize;
-
-    /// Returns the height of the `TextWriter`.
+    /// Returns the height of the `Screen`.
     fn get_height(&self) -> usize;
+    /// Returns the size of the `Screen`.
+    fn get_size(&self) -> usize;
+}
 
+/// A helper trait used to interact with various vga text modes.
+pub trait TextWriter: Screen {
     /// Sets the graphics device to a video mode as determined by
     /// the `TextWriter` implementation.
     fn set_mode(&self);

src/writers/text_40x25.rs

@@ -1,4 +1,4 @@
-use super::TextWriter;
+use super::{Screen, TextWriter};
 use crate::{
     colors::DEFAULT_PALETTE,
     fonts::TEXT_8X16_FONT,
@@ -29,7 +29,7 @@ const HEIGHT: usize = 25;
 #[derive(Default)]
 pub struct Text40x25;
 
-impl TextWriter for Text40x25 {
+impl Screen for Text40x25 {
     fn get_width(&self) -> usize {
         WIDTH
     }
@@ -38,6 +38,12 @@ impl TextWriter for Text40x25 {
         HEIGHT
     }
 
+    fn get_size(&self) -> usize {
+        WIDTH * HEIGHT
+    }
+}
+
+impl TextWriter for Text40x25 {
     /// Sets the graphics device to `VideoMode::Mode40x25`.
     fn set_mode(&self) {
         let mut vga = VGA.lock();

src/writers/text_40x50.rs

@@ -1,4 +1,4 @@
-use super::TextWriter;
+use super::{Screen, TextWriter};
 use crate::{
     colors::DEFAULT_PALETTE,
     fonts::TEXT_8X8_FONT,
@@ -29,7 +29,7 @@ const HEIGHT: usize = 50;
 #[derive(Default)]
 pub struct Text40x50;
 
-impl TextWriter for Text40x50 {
+impl Screen for Text40x50 {
     fn get_width(&self) -> usize {
         WIDTH
     }
@@ -38,6 +38,12 @@ impl TextWriter for Text40x50 {
         HEIGHT
     }
 
+    fn get_size(&self) -> usize {
+        WIDTH * HEIGHT
+    }
+}
+
+impl TextWriter for Text40x50 {
     /// Sets the graphics device to `VideoMode::Mode40x50`.
     fn set_mode(&self) {
         let mut vga = VGA.lock();

src/writers/text_80x25.rs

@@ -1,4 +1,4 @@
-use super::TextWriter;
+use super::{Screen, TextWriter};
 use crate::{
     colors::DEFAULT_PALETTE,
     fonts::TEXT_8X16_FONT,
@@ -29,7 +29,7 @@ const HEIGHT: usize = 25;
 #[derive(Default)]
 pub struct Text80x25;
 
-impl TextWriter for Text80x25 {
+impl Screen for Text80x25 {
     fn get_width(&self) -> usize {
         WIDTH
     }
@@ -38,6 +38,12 @@ impl TextWriter for Text80x25 {
         HEIGHT
     }
 
+    fn get_size(&self) -> usize {
+        WIDTH * HEIGHT
+    }
+}
+
+impl TextWriter for Text80x25 {
     fn set_mode(&self) {
         let mut vga = VGA.lock();
         vga.set_video_mode(VideoMode::Mode80x25);