Merge pull request 'cpu_text_sprite' (#1) from cpu_text_sprite into master

Reviewed-on: https://git.steins7.ovh/Steins7/canvas/pulls/1

.editorconfig

@@ -0,0 +1,5 @@
+[*.rs]
+indent_style = tab
+indent_size = 4
+max_line_length = 100
+

.gitignore

@@ -1,3 +1,6 @@
 /target
 *.log
 *.bkp
+*.perf
+*.data
+*.html

Cargo.lock

@@ -147,6 +147,7 @@ dependencies = [
  "cgmath",
  "chrono",
  "fern",
+ "fontdue",
  "image",
  "log",
  "pollster",
@@ -504,6 +505,16 @@ version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
 
+[[package]]
+name = "fontdue"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a62391ecb864cf12ed06b2af4eda2e609b97657950d6a8f06841b17726ab253"
+dependencies = [
+ "hashbrown 0.11.2",
+ "ttf-parser",
+]
+
 [[package]]
 name = "foreign-types"
 version = "0.3.2"
@@ -578,7 +589,7 @@ checksum = "0b0c02e1ba0bdb14e965058ca34e09c020f8e507a760df1121728e0aef68d57a"
 dependencies = [
  "bitflags",
  "gpu-descriptor-types",
- "hashbrown",
+ "hashbrown 0.12.3",
 ]
 
 [[package]]
@@ -590,6 +601,15 @@ dependencies = [
  "bitflags",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.11.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ab5ef0d4909ef3724cc8cce6ccc8572c5c817592e9285f5464f8e86f8bd3726e"
+dependencies = [
+ "ahash",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.12.3"
@@ -666,7 +686,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "10a35a97730320ffe8e2d410b5d3b69279b98d2c14bdb8b70ea89ecf7888d41e"
 dependencies = [
  "autocfg",
- "hashbrown",
+ "hashbrown 0.12.3",
 ]
 
 [[package]]
@@ -1319,6 +1339,12 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "ttf-parser"
+version = "0.15.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7b3e06c9b9d80ed6b745c7159c40b311ad2916abb34a49e9be2653b90db0d8dd"
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.5"

Cargo.toml

@@ -13,6 +13,7 @@ fern = { version = "^0.6.1", features = ["colored"] }
 bitflags = "^1.3.2"
 cgmath = { version = "^0.18.0", features = ["bytemuck"] }
 pollster = "^0.2.5"
+fontdue = "0.7.2"
 
 # surface creation
 winit = "^0.26.1"
@@ -33,3 +34,6 @@ features = ["png", "jpeg"]
 [patch.crates-io]
 cgmath = { path = "cgmath" }
 
+[profile.release]
+debug = 1
+

src/canvas.rs

@@ -28,7 +28,7 @@ pub trait Application<S> {
 //--Canvas struct-----------------------------------------------------------------------------------
 pub struct Canvas {
     default_texture: TextureHandle,
-    clear_color: Pixel,
+    clear_color: Color,
 
     renderer: WgpuRenderer,
 }
@@ -80,8 +80,14 @@ impl Canvas {
         )
     }
 
-    pub fn create_text_sprite(&mut self, _size: Size, _scale: f32) -> TextSprite {
-        unimplemented!();
+    pub fn create_text_sprite(&mut self, text: &'static str, size: Size, text_size: f32)
+        -> TextSprite {
+        TextSprite::new(
+            text,
+            size,
+            text_size,
+            &self.renderer,
+        )
     }
 
     pub fn create_shape_sprite(&mut self) -> ShapeSprite {
@@ -143,7 +149,7 @@ impl Canvas {
         sprite.render(&mut self.renderer);
     }
 
-    pub fn set_clear_color(&mut self, color: Pixel) {
+    pub fn set_clear_color(&mut self, color: Color) {
         self.clear_color = color;
     }
 

src/lib.rs

@@ -106,7 +106,7 @@ mod tests {
                     message
                 ))
             })
-            .level(log::LevelFilter::Trace)
+            .level(log::LevelFilter::Debug)
             .chain(std::io::stdout())
             .chain(fern::log_file("output.log")?)
             .apply()?;

src/main.rs

@@ -5,7 +5,7 @@ use canvas::{
     Application,
     Canvas,
     texture::TextureHandle,
-    sprite::TextureSprite,
+    sprite::{TextureSprite, TextSprite},
     utils::Position,
 };
 
@@ -40,10 +40,13 @@ struct ExampleState {
     pub texture: TextureHandle,
     pub tex_sprite: TextureSprite,
     pub sub_sprite: TextureSprite,
+    pub sub_sprite2: TextureSprite,
+    pub txt_sprite: TextSprite,
     pub last_instant: Instant,
     pub last_offset: u32,
     pub last_pos: Position,
     pub last_rot: f32,
+    pub frame_counter: u8,
 }
 
 struct ExampleApp {}
@@ -51,16 +54,35 @@ struct ExampleApp {}
 impl Application<ExampleState> for ExampleApp {
 
     fn init(canvas: &mut Canvas) -> Result<ExampleState, &'static str> {
-        use canvas::utils::Size;
+        use canvas::{
+            utils::{Size, Color},
+            sprite::{Sprite, Center},
+        };
 
         //// 20 x 20 sprite of a picture
         let texture = canvas.create_texture_from_file("assets/camel.jpg", None, None, None)
             .unwrap();
         let mut tex_sprite = canvas.create_texture_sprite(Size {w: 1280, h: 720});
         tex_sprite.set_texture(texture.clone(), Some(Position {x: 0, y: 0}), 1.0);
+        tex_sprite.set_center(Center::BotLeft);
+        tex_sprite.set_position(Position {x: 0, y: 0});
 
-        let mut sub_sprite = canvas.create_texture_sprite(Size {w: 200, h: 200});
-        sub_sprite.set_texture(texture.clone(), Some(Position {x: 350, y: 0}), 1.0);
+        let mut sub_sprite = canvas.create_texture_sprite(Size {w: 100, h: 100});
+        sub_sprite.set_texture(texture.clone(), Some(Position {x: 0, y: 0}), 1.0);
+        sub_sprite.set_position(Position {x: 100, y: 100});
+        sub_sprite.set_scale(2.0);
+
+        let mut sub_sprite2 = canvas.create_texture_sprite(Size {w: 200, h: 200});
+        sub_sprite2.set_texture(texture.clone(), Some(Position {x: 100, y: 0}), 1.0);
+        sub_sprite2.set_center(Center::Custom(Position {x:100, y:100}));
+        sub_sprite2.set_rotation(0.0);
+        sub_sprite2.set_position(Position {x: 100, y: 100});
+
+        let mut txt_sprite = canvas.create_text_sprite("00", Size {w: 100, h: 100}, 22.0);
+        txt_sprite.set_center(Center::BotLeft);
+        txt_sprite.set_position(Position {x:100, y:100});
+        txt_sprite.set_bg_color(Color::WHITE);
+        txt_sprite.set_scale(1.0);
 
         canvas.clear();
         canvas.update();
@@ -71,32 +93,54 @@ impl Application<ExampleState> for ExampleApp {
             texture,
             tex_sprite,
             sub_sprite,
+            sub_sprite2,
+            txt_sprite,
             last_instant,
             last_offset: 0,
-            last_pos: Position::origin(),
+            last_pos: Position {x: 0, y: 0},
             last_rot: 0.0,
+            frame_counter: 0,
         })
     }
 
     fn tick(state: &mut ExampleState, canvas: &mut Canvas) -> Result<(), &'static str> {
-        use canvas::sprite::Sprite;
+        use canvas::{
+            sprite::Sprite,
+            utils::Color,
+        };
 
         let now = Instant::now();
         let elapsed = now.duration_since(state.last_instant).as_millis();
         state.last_instant = now;
         debug!("frame time: {}ms", elapsed);
-
+        state.frame_counter += 1;
+        if state.frame_counter >= 60 {
+            state.frame_counter = 0;
+            state.txt_sprite.set_text(&format!("{}", elapsed));
+            state.txt_sprite.set_text_size(elapsed as f32);
+        }
+        match state.frame_counter {
+            0 => state.txt_sprite.set_fg_color(Color::RED),
+            20 => state.txt_sprite.set_fg_color(Color::BLUE),
+            40 => state.txt_sprite.set_fg_color(Color::GREEN),
+            _ => (),
+        }
         //state.sub_sprite.for_each(|pix| unsafe {pix.flat = pix.flat.wrapping_add(1);});
 
-        state.last_offset += 1;
-        state.last_pos.y += 1;
+       // state.last_offset += 1;
+        //state.last_pos.x += 1;
+        //state.last_pos.y += 1;
         state.last_rot += 1.0;
+        debug!("{:#?}", state.last_pos);
         state.tex_sprite.set_texture(state.texture.clone(), None, state.last_rot/100.0);
-        state.sub_sprite.set_texture(state.texture.clone(),
-                                     Some(Position {x: state.last_offset, y: 0}), 1.0);
-        state.sub_sprite.set_position(state.last_pos);
+       // state.sub_sprite.set_texture(state.texture.clone(),
+       //                             Some(Position {x: state.last_offset, y: 0}), 1.0);
+//        state.sub_sprite.set_position(state.last_pos);
+//        state.sub_sprite2.set_position(state.last_pos);
         state.sub_sprite.set_rotation(state.last_rot);
+        state.sub_sprite2.set_rotation(state.last_rot + 45.0);
 
+//		state.txt_sprite.set_rotation(state.last_rot);
         //state.sub_sprite.set_scale(state.last_rot/1000.0);
 
         // inputs
@@ -108,6 +152,7 @@ impl Application<ExampleState> for ExampleApp {
         //    unimplemented!();
         //}
         //
+        //
         //match canvas.get_key_presses() {
         //    Key::A => unimplemented!(),
         //    _ => (),
@@ -156,6 +201,8 @@ impl Application<ExampleState> for ExampleApp {
 
         canvas.draw(&mut state.tex_sprite);
         canvas.draw(&mut state.sub_sprite);
+        canvas.draw(&mut state.sub_sprite2);
+        canvas.draw(&mut state.txt_sprite);
         canvas.update();
 
         Ok(())

src/renderer.rs

@@ -4,7 +4,7 @@ use log::{debug, error, info, trace, warn};
 use raw_window_handle::HasRawWindowHandle;
 use wgpu;
 
-use crate::utils::{Pixel, Size};
+use crate::utils::{Color, Size};
 
 pub mod utils;
 
@@ -96,7 +96,11 @@ impl WgpuRenderer {
         })
     }
 
-    pub fn clear(&mut self, color: Pixel) {
+    pub fn get_surface_size(&self) -> Size {
+        self.surface_size
+    }
+
+    pub fn clear(&mut self, color: Color) {
 
         let view = self.create_texture_view();
         let mut encoder = self.device.create_command_encoder(&wgpu::CommandEncoderDescriptor {
@@ -221,16 +225,23 @@ impl WgpuRenderer {
 
 //--Renderer struct utils---------------------------------------------------------------------------
 
-impl From<Pixel> for wgpu::Color {
+//impl From<Pixel> for wgpu::Color {
+//
+//	fn from(value: Pixel) -> Self {
+//		Self {
+//			r: f64::from(value.r) / 255.0,
+//			g: f64::from(value.g) / 255.0,
+//			b: f64::from(value.b) / 255.0,
+//			a: f64::from(value.a) / 255.0,
+//		}
+//	}
+//}
 
-    fn from(pix: Pixel) -> Self {
-        let rgba = pix.to_rgba();
-        Self {
-            r: (rgba.r as f64) / 255.0,
-            g: (rgba.g as f64) / 255.0,
-            b: (rgba.b as f64) / 255.0,
-            a: (rgba.a as f64) / 255.0,
-        }
-    }
+impl From<Color> for wgpu::Color {
+
+	fn from(value: Color) -> Self {
+		value.into_wgpu_color()
+	}
 }
 
+

src/renderer/matrix.rs

@@ -16,8 +16,10 @@ pub const MATRIX_SIZE: usize = 48;//std::mem::size_of::<Matrix3<f32>>();
 //--ModelMatrix struct------------------------------------------------------------------------------
 pub struct ModelMatrix {
     position: Position,
+    center: Position,
     rotation: Deg<f32>,
     scale: f32,
+    aspect_matrix: Matrix3<f32>,
 
     uniform: Uniform<MATRIX_SIZE>,
     is_synced: bool,
@@ -26,19 +28,27 @@ pub struct ModelMatrix {
 impl ModelMatrix {
 
     pub fn new(renderer: &WgpuRenderer,
-               pos: Position,
-               rot: f32,
+               position: Position,
+               rotation: f32,
                scale: f32)
         -> Self
     {
+        let surface_size: Vector2<f32> = renderer.get_surface_size().into();
+        //A factor 2 is used since the gpu coords go from -1.0 to 1.0 while the engine coords only
+        //go from 0 to 1
+        let aspect_matrix = Matrix3::from_nonuniform_scale(2.0 / surface_size.x,
+														   2.0 / surface_size.y)
+			* Matrix3::from_translation(-surface_size / 2.0);
 
-       Self {
-           position: pos,
-           rotation: Deg (rot),
-           scale,
+        Self {
+            position,
+            center: Position::origin(),
+            rotation: Deg(rotation),
+            scale,
+            aspect_matrix,
 
-           uniform: Uniform::create(renderer, &renderer.matrix_layout),
-           is_synced: false,
+            uniform: Uniform::create(renderer, &renderer.matrix_layout),
+            is_synced: false,
        }
     }
 
@@ -46,13 +56,8 @@ impl ModelMatrix {
         Self::new(renderer, Position::origin(), 0.0, 1.0)
     }
 
-    pub fn set_position(&mut self, pos: Position) {
-        self.position = pos;
-        self.is_synced = false;
-    }
-
-    pub fn set_rotation(&mut self, rot: f32) {
-        self.rotation = Deg (rot);
+    pub fn set_position(&mut self, position: Position) {
+        self.position = position;
         self.is_synced = false;
     }
 
@@ -61,22 +66,37 @@ impl ModelMatrix {
         self.is_synced = false;
     }
 
+    pub fn set_rotation(&mut self, rotation: f32) {
+        self.rotation = Deg(rotation);
+        self.is_synced = false;
+    }
+
+    pub fn set_center(&mut self, center: Position) {
+        self.center = center;
+        self.is_synced = false;
+    }
+
     pub fn get_uniform(&mut self) -> &mut Uniform<MATRIX_SIZE> {
         use cgmath::{Basis3, Rotation3};
 
         if self.is_synced == false {
 
-            let pos_vec = Vector2 {
-                x: self.position.x as f32,
-                y: self.position.y as f32,
-            };
-            let rotation_mat = Matrix3::from(Basis3::from_angle_z(self.rotation));
-            let scale_mat = Matrix3::from_scale(self.scale);
-            let translation_mat = Matrix3::from_translation(pos_vec);
-            let aspect_mat = Matrix3::from_nonuniform_scale(1.0/1280.0, 1.0/720.0);
+            let position = Matrix3::from_translation(self.position.into());
+            let scale = Matrix3::from_scale(self.scale);
+            let center = Matrix3::from_translation((self.center * -1.0).into());
+            let rotation = Matrix3::from(Basis3::from_angle_z(self.rotation));
+
+			//to be read in reverse: scale is applied first, then the center offset is applied in
+			//reverse, so that it lines up with the world's origin. The rotation is then applied
+			//around the world's origin (and ence, the center). FInally, the translation is applied
+			//before the aspect matrix can move use from window-space (w x h) to normalized space
+			//(-1.0 to 1.0)
+            let matrix = self.aspect_matrix * position * rotation * center * scale;
 
-            let matrix = aspect_mat * translation_mat * rotation_mat * scale_mat;
             let mat_bytes: [u8; 36] = bytemuck::bytes_of(&matrix).try_into().unwrap();
+
+            //wgsl uses 16 bytes-aligned matrixes, but ours is 12 bytes-aligned. Fix that by adding
+            //4 paddings bytes after each 12 bytes
             let mut bytes = [0; 48];
             for i in 0..12 {
                 bytes[i] = mat_bytes[i];

src/renderer/utils.rs

@@ -123,7 +123,8 @@ where
             }
         );
 
-        let index_buffer = device.create_buffer( &wgpu_types::BufferDescriptor {
+        let index_buffer = device.create_buffer(
+			&wgpu_types::BufferDescriptor {
                 label: Some("Index Buffer"),
                 size: (I_NB * size_of::<u16>()) as u64,
                 usage: Usages::INDEX | Usages::COPY_DST,

src/sprite.rs

@@ -19,6 +19,16 @@ use crate::{
 
 //--External imports--------------------------------------------------------------------------------
 
+//--Center enum-------------------------------------------------------------------------------------
+pub enum Center {
+	Geometric,
+	TopLeft,
+	TopRight,
+	BotLeft,
+	BotRight,
+	Custom(Position),
+}
+
 //--Sprite trait------------------------------------------------------------------------------------
 
 /// The interface for everything that can be rendered by the engine.
@@ -27,19 +37,22 @@ use crate::{
 /// well as the unique function necessary for it to be rendered
 pub trait Sprite {
 
-    /// Set the position of the [Sprite] on the screen
-    fn set_position(&mut self, pos: Position);
+    /// Sets the position of the [`Sprite`] on the screen
+    fn set_position(&mut self, position: Position);
 
-    /// Set the rotation of the [Sprite] on the screen
-    fn set_rotation(&mut self, rot: f32);
+    /// Sets the center of the [`Sprite`] for rotations as well as translations
+    fn set_center(&mut self, center: Center);
 
-    /// Set the alpha of the [Sprite] on the screen
+    /// Sets the rotation of the [`Sprite`] on the screen
+    fn set_rotation(&mut self, rotation: f32);
+
+    /// Sets the alpha of the [`Sprite`] on the screen
     fn set_alpha(&mut self, alpha: u8);
 
-    /// Set the scale of the [Sprite] on the screen
+    /// Sets the scale of the [`Sprite`] on the screen
     fn set_scale(&mut self, scale: f32);
 
-    /// Renders the [Sprite] using the given rendering context
+    /// Renders the [`Sprite`] using the given rendering context
     fn render(&mut self, renderer: &mut WgpuRenderer);
 }
 

src/sprite/shaders/texture.wgsl

@@ -14,12 +14,12 @@ struct VertexOutput {
 var<uniform> model_matrix: mat3x3<f32>;
 
 @vertex
-fn vs_main(model: VertexInput) -> VertexOutput {
+fn vs_main(vertex: VertexInput) -> VertexOutput {
 
     var out: VertexOutput;
-    out.tex_coords = model.tex_coords;
-	out.clip_position 
-		= vec4<f32>(model_matrix * vec3<f32>(model.position, 1.0), 1.0);
+    out.tex_coords = vertex.tex_coords;
+	out.clip_position
+		= vec4<f32>(model_matrix * vec3<f32>(vertex.position, 1.0), 1.0);
     return out;
 }
 

src/sprite/shape_sprite.rs

@@ -5,7 +5,7 @@ use log::{debug, error, info, trace, warn};
 
 use crate::{
     renderer::WgpuRenderer,
-    sprite::Sprite,
+    sprite::{Sprite, Center},
     shape::Shape,
     utils::{Pixel, Position, Size},
 };
@@ -35,11 +35,15 @@ impl ShapeSprite {
 
 impl Sprite for ShapeSprite {
 
-    fn set_position(&mut self, _pos: Position) {
+    fn set_position(&mut self, _position: Position) {
         todo!();
     }
 
-    fn set_rotation(&mut self, _rot: f32) {
+    fn set_center(&mut self, _center: Center) {
+        todo!();
+    }
+
+    fn set_rotation(&mut self, _rotation: f32) {
         todo!();
     }
 

src/sprite/text_sprite.rs

@@ -5,53 +5,168 @@ use log::{debug, error, info, trace, warn};
 
 use crate::{
     renderer::WgpuRenderer,
-    sprite::Sprite,
-    utils::{Pixel, Position, Size},
+    sprite::{Sprite, Center},
+    utils::{Pixel, Color, Position, Size},
 };
+use super::TextureSprite;
 
 //--External imports--------------------------------------------------------------------------------
 
-use cgmath::Matrix4;
-
 //--TextSprite struct-------------------------------------------------------------------------------
-#[allow(dead_code)]
 pub struct TextSprite {
-    matrix: Matrix4<f32>,
-    size: Size,
-    text: &'static str, //TODO: temporary
+    texture_sprite: TextureSprite,
+
+    text: String,
+    text_size: f32,
+    fg_color: Color,
+    bg_color: Color,
+
+    font: fontdue::Font,
+    layout: fontdue::layout::Layout,
+    text_generation_needed: bool,
 }
 
 impl TextSprite {
 
-    pub fn set_text(&mut self, _text: &'static str) {
-        todo!();
+    pub fn new(text: &'static str, size: Size, text_size: f32, renderer: &WgpuRenderer) -> Self {
+        use crate::{
+            renderer::Texture,
+            texture::TextureHandle,
+        };
+        use fontdue::layout::{CoordinateSystem, Layout, TextStyle};
+
+        let font = Self::configure_font(text_size);
+        let mut layout = Layout::new(CoordinateSystem::PositiveYDown);
+
+        //configure text layout to fit sprite size, keep default settings
+        layout.append(&[&font], &TextStyle::new(text, text_size, 0));
+
+        //draw text to the texture
+        let raw_texture : Vec::<Pixel>
+            = vec![Color::NONE.into(); (size.h * size.w).try_into().unwrap()];
+
+        //create the texture
+        let texture = Texture::create(renderer, bytemuck::cast_slice(&raw_texture), size);
+        let texture_handle = TextureHandle::from_texture(texture);
+
+        let texture_sprite = TextureSprite::new(texture_handle, size, &renderer);
+
+        Self {
+            texture_sprite,
+            text: text.to_string(),
+            text_size,
+            fg_color: Color::BLACK,
+            bg_color: Color::NONE,
+            font,
+            layout,
+            text_generation_needed: true,
+        }
     }
 
-    pub fn set_color(&mut self, _color: Pixel) {
-        todo!();
+    pub fn set_text(&mut self, text: &str) {
+        self.text = text.to_string();
+        self.text_generation_needed = true;
+    }
+
+    pub fn set_text_size(&mut self, text_size: f32) {
+        self.text_size = text_size;
+        self.text_generation_needed = true;
+    }
+
+    pub fn set_fg_color(&mut self, color: Color) {
+        if self.fg_color != color {
+            self.fg_color = color;
+            self.text_generation_needed = true;
+        }
+    }
+
+    pub fn set_bg_color(&mut self, color: Color) {
+        if self.bg_color != color {
+            self.bg_color = color;
+            self.text_generation_needed = true;
+        }
+    }
+
+    fn generate_text(&mut self) {
+
+        self.layout.clear();
+        self.layout.append(&[&self.font],
+                           &fontdue::layout::TextStyle::new(&self.text, self.text_size, 0));
+
+        let size = self.texture_sprite.get_size();
+        self.texture_sprite.fill(self.bg_color.into());
+
+        //draw each glyph at the corresponding position on the texture
+        for glyph in self.layout.glyphs() {
+            let (_metrics, bitmap) = self.font.rasterize_config(glyph.key);
+
+            let glyph_x = glyph.x as usize;
+            let glyph_y = glyph.y as usize;
+            let size_w = size.w as usize;
+            let size_h = size.h as usize;
+
+            //only try to draw a glyph if its origin fits in the texture
+            if glyph_x < size_w && glyph_y < size_h {
+
+                //glyphs that do not fit on the texture are cropped at the edge of the latter
+                for x in 0..std::cmp::min(glyph.width, size_w - glyph_x) {
+                    for y in 0..std::cmp::min(glyph.height, size_h - glyph_y) {
+
+                        self.fg_color.set_alpha(bitmap[x + y * glyph.width]);
+
+                        self.texture_sprite.set_pixel(
+                            Position {
+                                x: (glyph_x + x) as i32,
+                                y: (glyph_y + y) as i32,
+                            },
+
+                            Color::alpha_blend(&self.fg_color, &self.bg_color).into()
+                        );
+            } } } }
+    }
+
+    fn configure_font(text_size: f32) -> fontdue::Font
+    {
+        let font = include_bytes!("../../assets/DejaVuSansMono.ttf");
+        let settings = fontdue::FontSettings {
+            scale: text_size,
+            ..fontdue::FontSettings::default()
+        };
+        fontdue::Font::from_bytes(&font[..], settings).unwrap()
     }
 }
 
 impl Sprite for TextSprite {
 
-    fn set_position(&mut self, _pos: Position) {
-        todo!();
+    fn set_position(&mut self, position: Position) {
+        self.texture_sprite.set_position(position);
     }
 
-    fn set_rotation(&mut self, _rot: f32) {
-        todo!();
+    fn set_center(&mut self, center: Center) {
+        self.texture_sprite.set_center(center);
     }
 
-    fn set_alpha(&mut self, _alpha: u8) {
-        todo!();
+    fn set_rotation(&mut self, rotation: f32) {
+        self.texture_sprite.set_rotation(rotation);
     }
 
-    fn set_scale(&mut self, _scale: f32) {
-        todo!();
+    fn set_alpha(&mut self, alpha: u8) {
+        self.texture_sprite.set_alpha(alpha);
     }
 
-    fn render(&mut self, _renderer: &mut WgpuRenderer) {
-        todo!();
+    fn set_scale(&mut self, scale: f32) {
+        self.texture_sprite.set_scale(scale);
+    }
+
+    fn render(&mut self, renderer: &mut WgpuRenderer) {
+
+        // generate text if any setting changed
+        if self.text_generation_needed == true {
+            self.generate_text();
+            self.text_generation_needed = false;
+        }
+
+        self.texture_sprite.render(renderer);
     }
 }
 

src/sprite/texture_sprite.rs

@@ -3,7 +3,7 @@ use log::{debug, error, info, trace, warn};
 
 //--Internal imports--------------------------------------------------------------------------------
 
-use super::Sprite;
+use super::{Sprite, Center};
 
 use crate::{
     texture::TextureHandle,
@@ -91,11 +91,20 @@ impl TextureSprite {
         self.texture.for_each_in_area(func, self.offset, self.inner_size);
     }
 
+    pub fn fill(&mut self, pixel: Pixel) {
+        self.texture.fill(pixel);
+    }
+
+    pub fn get_size(&self) -> Size {
+        self.texture.get_size()
+    }
+
     fn update_vertices(&mut self, renderer: &WgpuRenderer) {
 
         debug!("Updating vertices...");
         let size = self.texture.get_size();
 
+
         // compute normalized coordinates
         let x_size = self.inner_size.w as f32 / size.w as f32 * self.scale;
         let y_size = self.inner_size.h as f32 / size.h as f32 * self.scale;
@@ -103,8 +112,10 @@ impl TextureSprite {
         let y_offset = self.offset.y as f32 / size.h as f32;
 
         // compute mesh size
-        let w = self.inner_size.w as f32;
-        let h = self.inner_size.h as f32;
+
+		//divide by 2 since the quad's coords go from -0.5 to 0.5
+        let w = self.inner_size.w as f32 / 2.0;
+        let h = self.inner_size.h as f32 / 2.0;
 
         let mesh = [
             TextureVertex {
@@ -133,12 +144,36 @@ impl TextureSprite {
 
 impl Sprite for TextureSprite {
 
-    fn set_position(&mut self, pos: Position) {
-        self.matrix.set_position(pos);
+    fn set_position(&mut self, position: Position) {
+        self.matrix.set_position(position);
     }
 
-    fn set_rotation(&mut self, rot: f32) {
-        self.matrix.set_rotation(rot);
+    fn set_center(&mut self, center: Center) {
+        let center_pos = match center {
+            Center::Geometric => Position {x: 0, y: 0},
+            Center::TopLeft   => Position {
+				x: -(self.inner_size.w as i32) / 2,
+				y:  (self.inner_size.h as i32) / 2
+			},
+            Center::TopRight  => Position {
+				x:  (self.inner_size.w as i32) / 2,
+				y:  (self.inner_size.h as i32) / 2
+			},
+            Center::BotLeft   => Position {
+				x: -(self.inner_size.w as i32) / 2,
+				y: -(self.inner_size.h as i32) / 2
+			},
+            Center::BotRight  => Position {
+				x:  (self.inner_size.w as i32) / 2,
+				y: -(self.inner_size.h as i32) / 2
+			},
+            Center::Custom(pos) => pos,
+        };
+        self.matrix.set_center(center_pos);
+    }
+
+    fn set_rotation(&mut self, rotation: f32) {
+        self.matrix.set_rotation(rotation);
     }
 
     fn set_alpha(&mut self, _alpha: u8) {
@@ -235,7 +270,7 @@ fn initialize_pipeline(renderer: &WgpuRenderer) -> wgpu::RenderPipeline {
             entry_point: "fs_main",
             targets: &[Some(wgpu::ColorTargetState {
                 format: renderer.config.format,
-                blend: Some(wgpu::BlendState::REPLACE),
+                blend: Some(wgpu::BlendState::ALPHA_BLENDING),
                 write_mask: wgpu::ColorWrites::ALL,
             })],
         }),

src/texture.rs

@@ -30,7 +30,7 @@ impl TextureHandle {
 
         //TODO check pos ?
         let mut texture = self.texture.borrow_mut();
-        let width = texture.size.w;
+        let width = texture.size.w as i32;
         texture.buffer[(pos.x + pos.y*width) as usize] = pix;
         texture.is_synced = false;
     }
@@ -51,15 +51,21 @@ impl TextureHandle {
     {
         //TODO check offset and pos ?
         let mut texture = self.texture.borrow_mut();
-        let width = texture.size.w;
-        for x in offset.x..(offset.x + size.w) {
-            for y in offset.y..(offset.y + size.h) {
+        let width = texture.size.w as i32;
+        for x in offset.x..(offset.x + size.w as i32) {
+            for y in offset.y..(offset.y + size.h as i32) {
                 func(&mut texture.buffer[(x + y*width) as usize]);
             }
         }
         texture.is_synced = false;
     }
 
+    pub fn fill (&mut self, pixel: Pixel) {
+        let mut texture = self.texture.borrow_mut();
+        texture.buffer.fill(pixel);
+        texture.is_synced = false;
+    }
+
     pub fn texture(&self) -> &Rc<RefCell<Texture>> {
         //TODO improve that
         &self.texture
@@ -70,4 +76,3 @@ impl TextureHandle {
     }
 }
 
-

src/utils.rs

@@ -3,13 +3,13 @@ use log::{debug, error, info, trace, warn};
 
 use winit;
 
-use cgmath::Vector3;
+use cgmath::{Vector3, Vector2};
 
 //--Position struct---------------------------------------------------------------------------------
-#[derive(Copy, Clone)]
+#[derive(Copy, Clone, Debug)]
 pub struct Position {
-    pub x: u32, 
-    pub y: u32,
+    pub x: i32,
+    pub y: i32,
 }
 
 impl Position {
@@ -23,12 +23,19 @@ impl Position {
 }
 
 impl From<Position> for Vector3<f32> {
-    
+
     fn from(pos: Position) -> Self {
         Self::new(pos.x as f32, pos.y as f32, 0.0)
     }
 }
 
+impl From<Position> for Vector2<f32> {
+
+    fn from(pos: Position) -> Self {
+        Self::new(pos.x as f32, pos.y as f32)
+    }
+}
+
 impl std::ops::Add for Position {
     type Output = Self;
 
@@ -40,6 +47,17 @@ impl std::ops::Add for Position {
     }
 }
 
+impl std::ops::Mul<f32> for Position {
+    type Output = Self;
+
+    fn mul(self, rhs: f32) -> Self::Output {
+        Position {
+            x: ((self.x as f32) * rhs) as i32,
+            y: ((self.y as f32) * rhs) as i32,
+        }
+    }
+}
+
 //--Size struct-------------------------------------------------------------------------------------
 #[derive(Copy, Clone)]
 pub struct Size {
@@ -52,7 +70,7 @@ impl From<Size> for winit::dpi::Size {
     fn from(size: Size) -> Self {
         winit::dpi::Size::Physical (
             winit::dpi::PhysicalSize {
-                width: size.w, 
+                width: size.w,
                 height: size.h,
         })
     }
@@ -79,48 +97,118 @@ impl From<winit::dpi::PhysicalSize<u32>> for Size {
     }
 }
 
+impl From<Size> for Vector2<f32> {
+
+    fn from(size: Size) -> Self {
+        Self::new(size.w as f32, size.h as f32)
+    }
+}
+
 //--Pixel struct------------------------------------------------------------------------------------
-#[derive(Copy, Clone, bytemuck::Pod, bytemuck::Zeroable)]
-#[repr(C)]
-pub struct Rgba {
-    pub r: u8,
-    pub g: u8,
-    pub b: u8,
-    pub a: u8,
+#[repr(packed, C)]
+#[derive(Copy, Clone, PartialEq, bytemuck::Pod, bytemuck::Zeroable)]
+pub struct Pixel {
+	pub r: u8,
+	pub g: u8,
+	pub b: u8,
+	pub a: u8,
 }
 
-#[derive(Copy, Clone, bytemuck::Zeroable)]
-pub union Pixel {
-    pub flat: u32,
-    rgba: Rgba,
-}
+impl From<Color> for Pixel {
 
-unsafe impl bytemuck::Pod for Pixel {}
+	fn from(value: Color) -> Self {
+		value.into_pixel()
+	}
+}
 
 impl Pixel {
-    
-    pub fn rgb(r: u8, g: u8, b: u8) -> Pixel {
-        Pixel {
-            rgba: Rgba{r, g, b, a: 255},
-        }
-    }
 
-    pub fn to_rgba(&self) -> Rgba {
-        unsafe { self.rgba }
-    }
+    pub const fn from_hex(hex: u32) -> Self {
+		let bytes = hex.to_be_bytes();
+		Self { r: bytes[0], g: bytes[1], b: bytes[2], a: bytes[3] }
+	}
+
 }
 
 //--Color values------------------------------------------------------------------------------------
 #[non_exhaustive]
-pub struct Color;
-
-impl Color {
-    pub const NONE:  Pixel = Pixel {flat: 0x00000000};
-    pub const WHITE: Pixel = Pixel {flat: 0xffffffff};
-    pub const BLACK: Pixel = Pixel {flat: 0x000000ff};
-    pub const RED:   Pixel = Pixel {flat: 0xff0000ff};
-    pub const GREEN: Pixel = Pixel {flat: 0x00ff00ff};
-    pub const BLUE:  Pixel = Pixel {flat: 0x0000ffff};
+#[derive(Copy, Clone, PartialEq)]
+pub struct Color {
+	r: f32,
+	g: f32,
+	b: f32,
+	a: f32,
 }
 
+impl From<Pixel> for Color {
+
+	fn from(value: Pixel) -> Self {
+		Self {
+			r: f32::from(value.r) / 255.0,
+			g: f32::from(value.g) / 255.0,
+			b: f32::from(value.b) / 255.0,
+			a: f32::from(value.a) / 255.0,
+		}
+	}
+}
+
+impl Color {
+
+	pub fn set_alpha(&mut self, a: u8) {
+		self.a = f32::from(a) / 255.0;
+	}
+
+	pub fn from_rgb(r: u8, g: u8, b: u8) -> Self {
+        Pixel { r, g, b, a: 255 }.into()
+    }
+
+    pub fn from_rgba(r: u8, g: u8, b: u8, a: u8) -> Self {
+        Pixel { r, g, b, a }.into()
+    }
+
+	pub fn from_hex(hex: u32) -> Self {
+        Pixel::from_hex(hex).into()
+	}
+
+	pub fn into_pixel(self) -> Pixel {
+		//unsafe block is used here for "to_int_unchecked" since the struct's invariant garentees
+		//that the values are within [0.0, 1.0], meaning we won't ever overflow an u8
+		unsafe {
+			Pixel {
+				r: self.r.to_int_unchecked::<u8>() * 255,
+				g: self.g.to_int_unchecked::<u8>() * 255,
+				b: self.b.to_int_unchecked::<u8>() * 255,
+				a: self.a.to_int_unchecked::<u8>() * 255,
+			}
+		}
+	}
+
+	pub fn into_wgpu_color(self) -> wgpu::Color {
+		wgpu::Color {
+			r: f64::from(self.r),
+			g: f64::from(self.g),
+			b: f64::from(self.b),
+			a: f64::from(self.a),
+		}
+	}
+
+    pub fn alpha_blend(&self, other: &Self) -> Self {
+		//apply alpha compisting's "over" operator, see
+		//[https://en.wikipedia.org/wiki/Alpha_compositing] for more detail
+		let a = self.a + other.a * (1.0 - self.a);
+		Self {
+			r: (self.r * self.a + other.r * other.a * (1.0 - self.a)) / a,
+			g: (self.g * self.a + other.g * other.a * (1.0 - self.a)) / a,
+			b: (self.b * self.a + other.b * other.a * (1.0 - self.a)) / a,
+			a,
+		}
+    }
+
+    pub const NONE:  Self = Self {r: 0.0, g: 0.0, b: 0.0, a: 0.0};
+    pub const WHITE: Self = Self {r: 1.0, g: 1.0, b: 1.0, a: 1.0};
+    pub const BLACK: Self = Self {r: 0.0, g: 0.0, b: 0.0, a: 1.0};
+    pub const RED:   Self = Self {r: 1.0, g: 0.0, b: 0.0, a: 1.0};
+    pub const GREEN: Self = Self {r: 0.0, g: 1.0, b: 0.0, a: 1.0};
+    pub const BLUE:  Self = Self {r: 0.0, g: 0.0, b: 1.0, a: 1.0};
+}