Rewrite emulatorv1.0.0-alpha1

This is a complete rewrite and restructure of the entire emulator
project, as part of the effort in locking down the Bedrock specification
and in creating much better tooling for creating and using Bedrock
programs.

This commit adds a command-line argument scheme, an embedded assembler,
a headless emulator for use in non-graphical environments, deferred
window creation for programs that do not access the screen device,
and new versions of phosphor and bedrock-core. The new version of
phosphor supports multi-window programs, which will make it possible to
implement program forking in the system device later on, and the new
version of bedrock-core implements the final core specification.

4 files changed, 0 insertions, 399 deletions

diff --git a/src/devices/screen/draw_line.rs b/src/devices/screen/draw_line.rs
deleted file mode 100644
index 94066f4..0000000
--- a/src/devices/screen/draw_line.rs
+++ /dev/null
@@ -1,223 +0,0 @@
-use super::*;
-
-impl ScreenDevice {
-    pub fn draw_line(&mut self, colour: u8, layer: ScreenLayer) {
-        let [p0, p1] = [self.cursor, self.vector];
-        match (p0.x == p1.x, p0.y == p1.y) {
-            (false, false) =>   self.draw_diagonal_line(colour, layer),
-            (false,  true) => self.draw_horizontal_line(colour, layer),
-            ( true, false) =>   self.draw_vertical_line(colour, layer),
-            ( true,  true) =>           self.draw_pixel(colour, layer, p0),
-        };
-    }
-
-    pub fn draw_line_1bit(&mut self, params: u8, layer: ScreenLayer) {
-        let [p0, p1] = [self.cursor, self.vector];
-        match (p0.x == p1.x, p0.y == p1.y) {
-            (false, false) =>   self.draw_diagonal_line_1bit(params, layer),
-            (false,  true) => self.draw_horizontal_line_1bit(params, layer),
-            ( true, false) =>   self.draw_vertical_line_1bit(params, layer),
-            ( true,  true) =>           self.draw_pixel_1bit(params, layer, p0),
-        };
-    }
-
-    pub fn draw_pixel_1bit(&mut self, params: u8, layer: ScreenLayer, point: ScreenPosition) {
-        let dim = self.dimensions;
-        let sprite = self.sprite_buffer.get_1bit_sprite(params);
-        let colour = sprite[point.y as usize % 8][point.x as usize % 8];
-        if !dim.contains_point(point) || colour == 0xff { return }
-        let index = point.x as usize + ((dim.width as usize) * (point.y as usize));
-        match layer {
-            ScreenLayer::Background => self.background[index] = colour,
-            ScreenLayer::Foreground => self.foreground[index] = colour,
-        };
-    }
-
-    fn draw_horizontal_line(&mut self, colour: u8, layer: ScreenLayer) {
-        if let Some([x0, y, x1, _]) = self.find_vector_bounding_box() {
-            let screen_width = self.dimensions.width as usize;
-            let i = screen_width * y;
-            let buffer = match layer {
-                ScreenLayer::Background => &mut self.background,
-                ScreenLayer::Foreground => &mut self.foreground,
-            };
-            buffer[i+x0..=i+x1].fill(colour);
-        }
-    }
-
-    fn draw_horizontal_line_1bit(&mut self, params: u8, layer: ScreenLayer) {
-        if let Some([x0, y, x1, _]) = self.find_vector_bounding_box() {
-            let screen_width = self.dimensions.width as usize;
-            let i = screen_width * y;
-            let buffer = match layer {
-                ScreenLayer::Background => &mut self.background,
-                ScreenLayer::Foreground => &mut self.foreground,
-            };
-            let sprite = self.sprite_buffer.get_1bit_sprite(params);
-            let row = sprite[y % 8];
-            for x in x0..=x1 {
-                let colour = row[x % 8];
-                if colour != 0xff { buffer[i+x] = colour };
-            }
-        }
-    }
-
-    fn draw_vertical_line(&mut self, colour: u8, layer: ScreenLayer) {
-        if let Some([x, y0, _, y1]) = self.find_vector_bounding_box() {
-            let screen_width = self.dimensions.width as usize;
-            let mut i = (screen_width * y0) + x;
-            let buffer = match layer {
-                ScreenLayer::Background => &mut self.background,
-                ScreenLayer::Foreground => &mut self.foreground,
-            };
-            for _ in y0..=y1 {
-                buffer[i] = colour;
-                i += screen_width;
-            }
-        }
-    }
-
-    fn draw_vertical_line_1bit(&mut self, params: u8, layer: ScreenLayer) {
-        if let Some([x, y0, _, y1]) = self.find_vector_bounding_box() {
-            let screen_width = self.dimensions.width as usize;
-            let mut i = (screen_width * y0) + x;
-            let buffer = match layer {
-                ScreenLayer::Background => &mut self.background,
-                ScreenLayer::Foreground => &mut self.foreground,
-            };
-            let sprite = self.sprite_buffer.get_1bit_sprite(params);
-            let mut column = [0u8; 8];
-            for y in 0..8 { column[y] = sprite[y][x % 8] }
-            for y in y0..=y1 {
-                let colour = column[y % 8];
-                if colour != 0xff { buffer[i] = colour };
-                i += screen_width;
-            }
-        }
-    }
-
-    fn draw_diagonal_line(&mut self, colour: u8, layer: ScreenLayer) {
-        fn abs_diff(v0: u16, v1: u16) -> u16 {
-            let v = v1.wrapping_sub(v0);
-            if v > 0x8000 { !v + 1 } else { v }
-        }
-        let [p0, p1] = [self.cursor, self.vector];
-
-        // If the slope of the line is greater than 1.
-        if  abs_diff(p0.y, p1.y) > abs_diff(p0.x, p1.x) {
-            // Swap points 0 and 1 such that y0 is always smaller than y1.
-            let (x0, y0, x1, y1) = match p0.y > p1.y {
-                true  => (p1.x, p1.y, p0.x, p0.y),
-                false => (p0.x, p0.y, p1.x, p1.y),
-            };
-            let dy = y1 - y0;
-            let (dx, xi) = match x0 > x1 {
-                true  => (x0 - x1, 0xffff),
-                false => (x1 - x0, 0x0001),
-            };
-            let dxdy2 = (dx.wrapping_sub(dy)).wrapping_mul(2);
-            let dx2 = dx * 2;
-            let mut d = dx2.wrapping_sub(dy);
-            let mut x = x0;
-
-            for y in y0..=y1 {
-                self.draw_pixel(colour, layer, ScreenPosition::new(x, y));
-                if d < 0x8000 {
-                    x = x.wrapping_add(xi); d = d.wrapping_add(dxdy2);
-                } else {
-                    d = d.wrapping_add(dx2);
-                }
-            }
-        // If the slope of the line is less than or equal to 1.
-        } else {
-            // Swap points 0 and 1 so that x0 is always smaller than x1.
-            let (x0, y0, x1, y1) = match p0.x > p1.x {
-                true  => (p1.x, p1.y, p0.x, p0.y),
-                false => (p0.x, p0.y, p1.x, p1.y),
-            };
-            let dx = x1 - x0;
-            let (dy, yi) = match y0 > y1 {
-                true  => (y0 - y1, 0xffff),
-                false => (y1 - y0, 0x0001),
-            };
-            let dydx2 = (dy.wrapping_sub(dx)).wrapping_mul(2);
-            let dy2 = dy * 2;
-            let mut d = dy2.wrapping_sub(dx);
-            let mut y = y0;
-
-            for x in x0..=x1 {
-                self.draw_pixel(colour, layer, ScreenPosition::new(x, y));
-                if d < 0x8000 {
-                    y = y.wrapping_add(yi);
-                    d = d.wrapping_add(dydx2);
-                } else {
-                    d = d.wrapping_add(dy2);
-                }
-            }
-        }
-    }
-
-    fn draw_diagonal_line_1bit(&mut self, params: u8, layer: ScreenLayer) {
-        fn abs_diff(v0: u16, v1: u16) -> u16 {
-            let v = v1.wrapping_sub(v0);
-            if v > 0x8000 { !v + 1 } else { v }
-        }
-        let [p0, p1] = [self.cursor, self.vector];
-
-        // If the slope of the line is greater than 1.
-        if  abs_diff(p0.y, p1.y) > abs_diff(p0.x, p1.x) {
-            // Swap points 0 and 1 such that y0 is always smaller than y1.
-            let (x0, y0, x1, y1) = match p0.y > p1.y {
-                true  => (p1.x, p1.y, p0.x, p0.y),
-                false => (p0.x, p0.y, p1.x, p1.y),
-            };
-            let dy = y1 - y0;
-            let (dx, xi) = match x0 > x1 {
-                true  => (x0 - x1, 0xffff),
-                false => (x1 - x0, 0x0001),
-            };
-            let dxdy2 = (dx.wrapping_sub(dy)).wrapping_mul(2);
-            let dx2 = dx * 2;
-            let mut d = dx2.wrapping_sub(dy);
-            let mut x = x0;
-
-            for y in y0..=y1 {
-                self.draw_pixel_1bit(params, layer, ScreenPosition::new(x, y));
-                if d < 0x8000 {
-                    x = x.wrapping_add(xi); d = d.wrapping_add(dxdy2);
-                } else {
-                    d = d.wrapping_add(dx2);
-                }
-            }
-        // If the slope of the line is less than or equal to 1.
-        } else {
-            // Swap points 0 and 1 so that x0 is always smaller than x1.
-            let (x0, y0, x1, y1) = match p0.x > p1.x {
-                true  => (p1.x, p1.y, p0.x, p0.y),
-                false => (p0.x, p0.y, p1.x, p1.y),
-            };
-            let dx = x1 - x0;
-            let (dy, yi) = match y0 > y1 {
-                true  => (y0 - y1, 0xffff),
-                false => (y1 - y0, 0x0001),
-            };
-            let dydx2 = (dy.wrapping_sub(dx)).wrapping_mul(2);
-            let dy2 = dy * 2;
-            let mut d = dy2.wrapping_sub(dx);
-            let mut y = y0;
-
-            for x in x0..=x1 {
-                self.draw_pixel_1bit(params, layer, ScreenPosition::new(x, y));
-                if d < 0x8000 {
-                    y = y.wrapping_add(yi);
-                    d = d.wrapping_add(dydx2);
-                } else {
-                    d = d.wrapping_add(dy2);
-                }
-            }
-        }
-    }
-
-
-
-}
diff --git a/src/devices/screen/draw_rect.rs b/src/devices/screen/draw_rect.rs
deleted file mode 100644
index 265a87f..0000000
--- a/src/devices/screen/draw_rect.rs
+++ /dev/null
@@ -1,42 +0,0 @@
-use super::*;
-
-impl ScreenDevice {
-    pub fn draw_rect(&mut self, colour: u8, layer: ScreenLayer) {
-        if let Some([x0, y0, x1, y1]) = self.find_vector_bounding_box() {
-            let screen_width = self.dimensions.width as usize;
-            let rect_width = x1 - x0 + 1;
-            let mut i = x0 + (screen_width * y0);
-            let buffer = match layer {
-                ScreenLayer::Background => &mut self.background,
-                ScreenLayer::Foreground => &mut self.foreground,
-            };
-            for _ in y0..=y1 {
-                buffer[i..i+rect_width].fill(colour);
-                i += screen_width;
-            }
-        }
-    }
-
-    pub fn draw_rect_1bit(&mut self, params: u8, layer: ScreenLayer) {
-        if let Some([x0, y0, x1, y1]) = self.find_vector_bounding_box() {
-            let screen_width = self.dimensions.width as usize;
-            let rect_width = x1 - x0 + 1;
-            let mut i = x0 + (screen_width * y0);
-            let sprite = self.sprite_buffer.get_1bit_sprite(params);
-            let buffer = match layer {
-                ScreenLayer::Background => &mut self.background,
-                ScreenLayer::Foreground => &mut self.foreground,
-            };
-
-            for y in y0..=y1 {
-                let row = sprite[y % 8];
-                for x in x0..=x1 {
-                    let colour = row[x % 8];
-                    if colour != 0xff { buffer[i] = colour }
-                    i += 1;
-                }
-                i += screen_width - rect_width;
-            }
-        };
-    }
-}
diff --git a/src/devices/screen/draw_sprite.rs b/src/devices/screen/draw_sprite.rs
deleted file mode 100644
index 5676335..0000000
--- a/src/devices/screen/draw_sprite.rs
+++ /dev/null
@@ -1,25 +0,0 @@
-use super::*;
-
-impl ScreenDevice {
-    pub fn draw_sprite_1bit(&mut self, params: u8, layer: ScreenLayer) {
-        let sprite = self.sprite_buffer.get_1bit_sprite(params);
-        self.draw_sprite(sprite, layer);
-    }
-
-    pub fn draw_sprite_2bit(&mut self, params: u8, layer: ScreenLayer) {
-        let sprite = self.sprite_buffer.get_2bit_sprite(params);
-        self.draw_sprite(sprite, layer);
-    }
-
-    fn draw_sprite(&mut self, sprite: Sprite, layer: ScreenLayer) {
-        let mut pos = self.cursor;
-        for row in sprite {
-            for colour in row {
-                self.draw_pixel(colour, layer, pos);
-                pos.x = pos.x.wrapping_add(1);
-            }
-            pos.x = pos.x.wrapping_sub(8);
-            pos.y = pos.y.wrapping_add(1);
-        }
-    }
-}
diff --git a/src/devices/screen/sprite_data.rs b/src/devices/screen/sprite_data.rs
deleted file mode 100644
index 0a1d3c2..0000000
--- a/src/devices/screen/sprite_data.rs
+++ /dev/null
@@ -1,109 +0,0 @@
-use super::*;
-
-macro_rules! test { ($value:expr, $mask:expr) => { $value & $mask != 0 }; }
-
-
-pub struct SpriteBuffer {
-    data: [u8; 16],
-    pointer: usize,
-    colours: [u8; 4],
-}
-
-impl SpriteBuffer {
-    pub fn new() -> Self {
-        Self { data: [0; 16], pointer: 0, colours: [0; 4] }
-    }
-
-    pub fn push(&mut self, val: u8) {
-        self.data[self.pointer] = val;
-        self.pointer = (self.pointer + 1) % 16;
-    }
-
-    pub fn set_colour_high(&mut self, val: u8) {
-        self.colours[0] = val >> 4;
-        self.colours[1] = val & 0x0f;
-    }
-
-    pub fn set_colour_low(&mut self, val: u8) {
-        self.colours[2] = val >> 4;
-        self.colours[3] = val & 0x0f;
-    }
-
-    // Return the 64 transformed pixels of the current 1-bit sprite.
-    // Each pixel is the palette index of that pixel, or 0xff if transparent.
-    pub fn get_1bit_sprite(&self, params: u8) -> Sprite {
-        let mut sprite = [[0u8; 8]; 8];
-        let plane = self.get_low_plane(params);
-        let colours = self.get_colours(params);
-        for (y, row) in plane.into_iter().enumerate() {
-            for x in (0..8).rev() {
-                sprite[y][7-x] = colours[(row >> x & 0x1) as usize];
-            }
-        }
-        return sprite;
-    }
-
-    // Return the 64 transformed pixels of the current 2-bit sprite.
-    // Each pixel is the palette index of that pixel, or 0xff if transparent.
-    pub fn get_2bit_sprite(&self, params: u8) -> Sprite {
-        let mut sprite = [[0u8; 8]; 8];
-        let high_plane = self.get_high_plane(params);
-        let low_plane = self.get_low_plane(params);
-        let colours = self.get_colours(params);
-        for (y, (row_h, row_l)) in zip(high_plane, low_plane).enumerate() {
-            for x in (0..8).rev() {
-                let bit_h = (row_h >> x) & 0x1;
-                let bit_l = (row_l >> x) & 0x1;
-                sprite[y][7-x] = colours[(bit_h << 1 | bit_l) as usize];
-            }
-        }
-        return sprite;
-    }
-
-    fn get_high_plane(&self, params: u8) -> Plane {
-        let mut plane = [0u8; 8];
-        for (i, row) in plane.iter_mut().enumerate() {
-            *row = self.data[(self.pointer + i) % 16]
-        }
-        transform_plane(plane, params)
-    }
-
-    fn get_low_plane(&self, params: u8) -> Plane {
-        let mut plane = [0u8; 8];
-        for (i, row) in plane.iter_mut().enumerate() {
-            *row = self.data[(self.pointer + i + 8) % 16]
-        }
-        transform_plane(plane, params)
-    }
-
-    fn get_colours(&self, params: u8) -> [u8; 4] {
-        let mut colours = self.colours;
-        if test!(params, TRANSPARENT) {
-            colours[0] = 0xff;
-        }
-        return colours;
-    }
-}
-
-fn transform_plane(mut plane: Plane, params: u8) -> Plane {
-    if test!(params, FLIP_DIAGONAL) {
-        let mut flipped = [0u8; 8];
-        for mut row in plane {
-            for y in 0..8 {
-                flipped[y] = flipped[y] << 1 | row >> 7;
-                row <<= 1;
-            }
-        }
-        plane = flipped;
-    }
-    if test!(params, FLIP_VERTICAL) {
-        plane.reverse();
-    }
-    if test!(params, FLIP_HORIZONTAL) {
-        for row in plane.iter_mut() {
-            *row = row.reverse_bits();
-        }
-    }
-    return plane;
-}
-