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/*
* Copyright 2021 QuantumBadger
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
//! Hardware-accelerated drawing of shapes, images, and text, with an easy to
//! use API.
//!
//! Speedy2D aims to be:
//!
//! - The simplest Rust API for creating a window, rendering graphics/text, and
//! handling input
//! - Compatible with any device supporting OpenGL 2.0+ or WebGL 2.0. Support
//! for OpenGL ES 2.0+ is planned.
//! - Very fast
//!
//! Supports Windows, Mac, Linux, and WebGL. Support for Android and iOS is in
//! development.
//!
//! By default, Speedy2D contains support for setting up a window with an OpenGL
//! context. If you'd like to handle this yourself, and use Speedy2D only for
//! rendering, you can disable the `windowing` feature.
//!
//! # Useful Links
//!
//! * [Source repository](https://github.com/QuantumBadger/Speedy2D)
//! * [Crate](https://crates.io/crates/speedy2d)
//!
//! # Getting Started (Windows/Mac/Linux)
//!
//! ## Create a window
//!
//! After adding Speedy2D to your Cargo.toml dependencies, create a window as
//! follows:
//!
//! ```rust,no_run
//! use speedy2d::Window;
//!
//! let window = Window::new_centered("Title", (640, 480)).unwrap();
//! ```
//!
//! You may also use [Window::new_fullscreen_borderless()],
//! [Window::new_with_options()], or [Window::new_with_user_events()].
//!
//! ## Implement the callbacks
//!
//! Create a struct implementing the `WindowHandler` trait. Override
//! whichever callbacks you're interested in, for example `on_draw()`,
//! `on_mouse_move()`, or `on_key_down()`.
//!
//! ```
//! use speedy2d::window::{WindowHandler, WindowHelper};
//! use speedy2d::Graphics2D;
//!
//! struct MyWindowHandler {}
//!
//! impl WindowHandler for MyWindowHandler
//! {
//! fn on_draw(&mut self, helper: &mut WindowHelper, graphics: &mut Graphics2D)
//! {
//! // Draw things here using `graphics`
//! }
//! }
//! ```
//!
//! The full list of possible callbacks is currently as follows. See
//! [WindowHandler] for full documentation.
//!
//! It's only necessary to implement the callbacks you actually want to use. The
//! default implementation will do nothing and continue the event loop.
//!
//! ```text
//! fn on_start()
//! fn on_user_event()
//! fn on_resize()
//! fn on_scale_factor_changed()
//! fn on_draw()
//! fn on_mouse_move()
//! fn on_mouse_button_down()
//! fn on_mouse_button_up()
//! fn on_key_down()
//! fn on_key_up()
//! fn on_keyboard_char()
//! fn on_keyboard_modifiers_changed()
//! ```
//!
//! Each callback gives you a [window::WindowHelper] instance, which
//! lets you perform window-related actions, like requesting that a new frame is
//! drawn using [window::WindowHelper::request_redraw()].
//!
//! Note: Unless you call [window::WindowHelper::request_redraw()], frames will
//! only be drawn when necessary, for example when resizing the window.
//!
//! ## Render some graphics
//!
//! The [WindowHandler::on_draw()] callback gives you a [Graphics2D]
//! instance, which lets you draw shapes, text, and images.
//!
//! ```
//! # use speedy2d::window::{WindowHandler, WindowHelper};
//! # use speedy2d::Graphics2D;
//! # use speedy2d::color::Color;
//! #
//! # struct MyWindowHandler {}
//! #
//! # impl WindowHandler for MyWindowHandler
//! # {
//! fn on_draw(&mut self, helper: &mut WindowHelper, graphics: &mut Graphics2D)
//! {
//! graphics.clear_screen(Color::from_rgb(0.8, 0.9, 1.0));
//! graphics.draw_circle((100.0, 100.0), 75.0, Color::BLUE);
//!
//! // Request that we draw another frame once this one has finished
//! helper.request_redraw();
//! }
//! # }
//! ```
//!
//! ## Start it running!
//!
//! Once you've implemented the callbacks you're interested in, start the event
//! loop running with [Window::run_loop()]:
//!
//! ```rust,no_run
//! # use speedy2d::Window;
//! # struct MyWindowHandler {}
//! # impl speedy2d::window::WindowHandler for MyWindowHandler {}
//! let window = Window::<()>::new_centered("Title", (640, 480)).unwrap();
//!
//! window.run_loop(MyWindowHandler{});
//! ```
//!
//! ## Alternative: Managing the GL context yourself
//!
//! If you'd rather handle the window creation and OpenGL context management
//! yourself, simply disable Speedy2D's `windowing` feature in your `Cargo.toml`
//! file, and create a context as follows. You will need to specify a loader
//! function to allow Speedy2D to obtain the OpenGL function pointers.
//!
//! ```rust,no_run
//! use speedy2d::GLRenderer;
//! # struct WindowContext {}
//! # impl WindowContext {
//! # fn get_proc_address(&self, fn_name: &str) -> *const std::ffi::c_void
//! # {
//! # std::ptr::null()
//! # }
//! # }
//! # let window_context = WindowContext {};
//!
//! let mut renderer = unsafe {
//! GLRenderer::new_for_gl_context((640, 480), |fn_name| {
//! window_context.get_proc_address(fn_name) as *const _
//! })
//! }.unwrap();
//! ```
//!
//! Then, draw a frame using [GLRenderer::draw_frame()]:
//!
//! ```rust,no_run
//! # use speedy2d::GLRenderer;
//! # use speedy2d::color::Color;
//! # let mut renderer = unsafe {
//! # GLRenderer::new_for_current_context((640, 480))
//! # }.unwrap();
//! renderer.draw_frame(|graphics| {
//! graphics.clear_screen(Color::WHITE);
//! graphics.draw_circle((100.0, 100.0), 75.0, Color::BLUE);
//! });
//! ```
//!
//! # Laying out text
//!
//! To render text, a font must be created. Call [font::Font::new()] with the
//! bytes from the TTF or OTF font file.
//!
//! (note: OTF support may be limited)
//!
//! ```rust,no_run
//! use speedy2d::font::Font;
//!
//! let bytes = include_bytes!("../assets/fonts/NotoSans-Regular.ttf");
//! let font = Font::new(bytes).unwrap();
//! ```
//!
//! Then, invoke `font.layout_text()` (part of the [font::TextLayout] trait) to
//! calculate the necessary line breaks and spacing. This will give you
//! a [font::FormattedTextBlock].
//!
//! ```rust,no_run
//! # use speedy2d::font::{Font, TextOptions};
//! # let font = Font::new(&[]).unwrap();
//! use speedy2d::font::TextLayout;
//!
//! let block = font.layout_text("Hello World", 32.0, TextOptions::new());
//! ```
//!
//! Finally, call [Graphics2D::draw_text()] to draw the text block!
//!
//! ```rust,no_run
//! # use speedy2d::GLRenderer;
//! # use speedy2d::color::Color;
//! # use speedy2d::font::{Font, TextOptions, TextLayout};
//! # let font = Font::new(&[]).unwrap();
//! # let block = font.layout_text("Hello World", 32.0, TextOptions::new());
//! # let mut renderer = unsafe {
//! # GLRenderer::new_for_current_context((640, 480))
//! # }.unwrap();
//! # renderer.draw_frame(|graphics| {
//! graphics.draw_text((100.0, 100.0), Color::BLUE, &block);
//! # });
//! ```
//!
//! ## Word wrap
//!
//! To wrap lines of text to a certain width, use
//! [font::TextOptions::with_wrap_to_width()]:
//!
//! ```rust,no_run
//! # use speedy2d::font::{Font, TextOptions};
//! # let font = Font::new(&[]).unwrap();
//! use speedy2d::font::{TextLayout, TextAlignment};
//!
//! let block = font.layout_text(
//! "The quick brown fox jumps over the lazy dog.",
//! 32.0,
//! TextOptions::new().with_wrap_to_width(300.0, TextAlignment::Left));
//! ```
//!
//! # Loading images
//!
//! Image files (in formats such as PNG, JPG, and BMP) can be loaded using the
//! following APIs, available in both `Graphics2D` and `GLRenderer`.
//!
//! * [Graphics2D::create_image_from_file_path()]
//! * [Graphics2D::create_image_from_file_bytes()]
//! * [GLRenderer::create_image_from_file_path()]
//! * [GLRenderer::create_image_from_file_bytes()]
//!
//! Alternatively, you can create an image from raw pixel data, using:
//!
//! * [Graphics2D::create_image_from_raw_pixels()]
//! * [GLRenderer::create_image_from_raw_pixels()]
//!
//! # Getting Started (WebGL)
//!
//! To use Speedy2D with WebGL, your app must be compiled for WebAssembly.
//! Speedy2D can attach itself to a `canvas` on the page using an ID you
//! specify.
//!
//! As with Windows/Mac/Linux targets, it's possible to use Speedy2D either in a
//! full rendering and event handling configuation, or for rendering only.
//!
//! For rendering only, use the following API:
//!
//! * [GLRenderer::new_for_web_canvas_by_id()]
//!
//! For full keyboard/mouse/etc event handling in addition to rendering, use:
//!
//! * [WebCanvas::new_for_id()]
//! * [WebCanvas::new_for_id_with_user_events()]
//!
//! After initialization, the usual [WindowHandler] callbacks and
//! [window::WindowHelper]/[Graphics2D] APIs should operate as on other
//! platforms.
//!
//! For an example, see the `examples/webgl` directory. To build this, first
//! install the prerequisites:
//!
//! ```shell
//! cargo install wasm-bindgen-cli just
//! ```
//!
//! Then use the following command to run the build:
//!
//! ```shell
//! just build-example-webgl
//! ```
#![deny(warnings)]
#![deny(missing_docs)]
use std::fmt::{Display, Formatter};
#[cfg(any(doc, doctest, all(target_arch = "wasm32", feature = "windowing")))]
use std::marker::PhantomData;
use std::rc::Rc;
#[cfg(any(feature = "image-loading", doc, doctest))]
use {
crate::image::ImageFileFormat,
std::io::{BufRead, Seek},
std::path::Path
};
use crate::color::Color;
use crate::dimen::{UVec2, Vec2};
use crate::error::{BacktraceError, ErrorMessage};
use crate::font::FormattedTextBlock;
use crate::glbackend::GLBackend;
#[cfg(not(target_arch = "wasm32"))]
use crate::glbackend::{GLBackendGLRS, GLBackendGlow};
use crate::glwrapper::{GLContextManager, GLVersion};
use crate::image::{ImageDataType, ImageHandle, ImageSmoothingMode, RawBitmapData};
use crate::renderer2d::Renderer2D;
use crate::shape::{Polygon, Rect, Rectangle};
#[cfg(target_arch = "wasm32")]
use crate::web::WebCanvasElement;
#[cfg(any(doc, doctest, feature = "windowing"))]
use crate::window::WindowHandler;
#[cfg(any(doc, doctest, all(feature = "windowing", not(target_arch = "wasm32"))))]
use crate::window::{
UserEventSender,
WindowCreationError,
WindowCreationOptions,
WindowPosition,
WindowSize
};
#[cfg(any(doc, doctest))]
use crate::window_internal_doctest::{WebCanvasImpl, WindowGlutin};
#[cfg(all(
feature = "windowing",
not(target_arch = "wasm32"),
not(any(doc, doctest))
))]
use crate::window_internal_glutin::WindowGlutin;
#[cfg(all(feature = "windowing", target_arch = "wasm32", not(any(doc, doctest))))]
use crate::window_internal_web::WebCanvasImpl;
/// Types representing colors.
pub mod color;
/// Types representing shapes.
pub mod shape;
/// Components for loading fonts and laying out text.
pub mod font;
/// Types representing sizes and positions.
pub mod dimen;
/// Utilities and traits for numeric values.
pub mod numeric;
/// Error types.
pub mod error;
/// Types relating to images.
pub mod image;
/// Utilities for accessing the system clock on all platforms.
pub mod time;
/// Allows for the creation and management of windows.
#[cfg(any(doc, doctest, feature = "windowing"))]
pub mod window;
#[cfg(all(
feature = "windowing",
not(target_arch = "wasm32"),
not(any(doc, doctest))
))]
mod window_internal_glutin;
#[cfg(all(feature = "windowing", target_arch = "wasm32", not(any(doc, doctest))))]
mod window_internal_web;
#[cfg(any(doc, doctest))]
mod window_internal_doctest;
#[cfg(any(target_arch = "wasm32"))]
mod web;
mod font_cache;
mod glbackend;
mod glwrapper;
mod renderer2d;
mod texture_packer;
mod utils;
/// An error encountered during the creation of a [GLRenderer].
#[derive(Clone, Debug)]
pub struct GLRendererCreationError
{
description: String
}
impl GLRendererCreationError
{
fn msg_with_cause<S, Cause>(description: S, cause: Cause) -> BacktraceError<Self>
where
S: AsRef<str>,
Cause: std::error::Error + 'static
{
BacktraceError::new_with_cause(
Self {
description: description.as_ref().to_string()
},
cause
)
}
#[allow(dead_code)]
fn msg<S>(description: S) -> BacktraceError<Self>
where
S: AsRef<str>
{
BacktraceError::new(Self {
description: description.as_ref().to_string()
})
}
}
impl Display for GLRendererCreationError
{
fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result
{
Display::fmt("GL renderer creation error: ", f)?;
Display::fmt(&self.description, f)
}
}
/// A graphics renderer using an OpenGL backend.
///
/// Note: There is no need to use this struct if you are letting Speedy2D create
/// a window for you.
pub struct GLRenderer
{
context: GLContextManager,
renderer: Graphics2D
}
impl GLRenderer
{
/// Creates a `GLRenderer` for the current OpenGL context.
/// `viewport_size_pixels` should be set to the initial viewport size,
/// however this can be changed later using [GLRenderer::
/// set_viewport_size_pixels()].
///
/// Note: This function must not be called if you are letting Speedy2D
/// create a window for you.
///
/// # Deprecation
///
/// Note: This function will be removed in a future version of Speedy2D.
/// Please use [GLRenderer::new_for_gl_context] instead.
///
/// # Safety
///
/// While a `GLRenderer` object is active, you must not make any changes to
/// the active GL context. Doing so may lead to undefined behavior,
/// which is why this function is marked `unsafe`. It is strongly
/// advised not to use any other OpenGL libraries in the same thread
/// as `GLRenderer`.
#[cfg(not(target_arch = "wasm32"))]
pub unsafe fn new_for_current_context<V: Into<UVec2>>(
viewport_size_pixels: V
) -> Result<Self, BacktraceError<GLRendererCreationError>>
{
Self::new_with_gl_backend(
viewport_size_pixels,
Rc::new(GLBackendGLRS {}),
GLVersion::OpenGL2_0
)
}
/// Creates a `GLRenderer` with the specified OpenGL loader function. The
/// loader function takes the name of an OpenGL function, and returns the
/// associated function pointer. `viewport_size_pixels` should be set to
/// the initial viewport size, however this can be changed later using
/// [GLRenderer:: set_viewport_size_pixels()].
///
/// Note: This function must not be called if you are letting Speedy2D
/// create a window for you.
///
/// # Safety
///
/// While a `GLRenderer` object is active, you must not make any changes to
/// the active GL context. Doing so may lead to undefined behavior,
/// which is why this function is marked `unsafe`. It is strongly
/// advised not to use any other OpenGL libraries in the same thread
/// as `GLRenderer`.
#[cfg(not(target_arch = "wasm32"))]
pub unsafe fn new_for_gl_context<V, F>(
viewport_size_pixels: V,
loader_function: F
) -> Result<Self, BacktraceError<GLRendererCreationError>>
where
V: Into<UVec2>,
F: FnMut(&str) -> *const std::os::raw::c_void
{
let backend =
GLBackendGlow::new(glow::Context::from_loader_function(loader_function));
Self::new_with_gl_backend(
viewport_size_pixels,
Rc::new(backend),
GLVersion::OpenGL2_0
)
}
/// Creates a `GLRenderer` for the specified HTML canvas. The canvas
/// will be found based on the specified ID.
///
/// The parameter `viewport_size_pixels` should be set to
/// the initial canvas size, however this can be changed later using
/// [GLRenderer:: set_viewport_size_pixels()].
#[cfg(any(doc, doctest, target_arch = "wasm32"))]
pub fn new_for_web_canvas_by_id<V, S>(
viewport_size_pixels: V,
element_id: S
) -> Result<Self, BacktraceError<GLRendererCreationError>>
where
V: Into<UVec2>,
S: AsRef<str>
{
WebCanvasElement::new_by_id(element_id.as_ref())
.map_err(|err| {
GLRendererCreationError::msg_with_cause("Failed to get canvas", err)
})?
.get_webgl2_context(viewport_size_pixels)
}
fn new_with_gl_backend<V: Into<UVec2>>(
viewport_size_pixels: V,
gl_backend: Rc<dyn GLBackend>,
gl_version: GLVersion
) -> Result<Self, BacktraceError<GLRendererCreationError>>
{
let viewport_size_pixels = viewport_size_pixels.into();
let context =
GLContextManager::create(gl_backend, gl_version).map_err(|err| {
GLRendererCreationError::msg_with_cause(
"GL context manager creation failed",
err
)
})?;
let renderer = Graphics2D {
renderer: Renderer2D::new(&context, viewport_size_pixels).map_err(|err| {
GLRendererCreationError::msg_with_cause("Renderer2D creation failed", err)
})?
};
Ok(GLRenderer { context, renderer })
}
/// Sets the renderer viewport to the specified pixel size, in response to a
/// change in the window size.
pub fn set_viewport_size_pixels(&mut self, viewport_size_pixels: UVec2)
{
self.renderer
.renderer
.set_viewport_size_pixels(viewport_size_pixels)
}
/// Creates a new [ImageHandle] from the specified raw pixel data.
///
/// The data provided in the `data` parameter must be in the format
/// specified by `data_type`.
///
/// The returned [ImageHandle] is valid only for the current graphics
/// context.
pub fn create_image_from_raw_pixels(
&mut self,
data_type: ImageDataType,
smoothing_mode: ImageSmoothingMode,
size: UVec2,
data: &[u8]
) -> Result<ImageHandle, BacktraceError<ErrorMessage>>
{
self.renderer
.create_image_from_raw_pixels(data_type, smoothing_mode, size, data)
}
/// Loads an image from the specified file path.
///
/// If no `data_type` is provided, an attempt will be made to guess the file
/// format.
///
/// For a list of supported image types, see [image::ImageFileFormat].
///
/// The returned [ImageHandle] is valid only for the current graphics
/// context.
#[cfg(any(feature = "image-loading", doc, doctest))]
pub fn create_image_from_file_path<S: AsRef<Path>>(
&mut self,
data_type: Option<ImageFileFormat>,
smoothing_mode: ImageSmoothingMode,
path: S
) -> Result<ImageHandle, BacktraceError<ErrorMessage>>
{
self.renderer
.create_image_from_file_path(data_type, smoothing_mode, path)
}
/// Loads an image from the provided encoded image file data.
///
/// If no `data_type` is provided, an attempt will be made to guess the file
/// format.
///
/// The data source must implement `std::io::BufRead` and `std::io::Seek`.
/// For example, if you have a `&[u8]`, you may wrap it in a
/// `std::io::Cursor` as follows:
///
/// ```rust,no_run
/// # use speedy2d::GLRenderer;
/// # use speedy2d::color::Color;
/// # use speedy2d::image::ImageSmoothingMode;
/// use std::io::Cursor;
/// # let mut renderer = unsafe {GLRenderer::new_for_current_context((0,0))}.unwrap();
///
/// let image_bytes : &[u8] = include_bytes!("../assets/screenshots/hello_world.png");
///
/// let image_result = renderer.create_image_from_file_bytes(
/// None,
/// ImageSmoothingMode::Linear,
/// Cursor::new(image_bytes));
/// ```
///
/// For a list of supported image types, see [image::ImageFileFormat].
///
/// The returned [ImageHandle] is valid only for the current graphics
/// context.
#[cfg(any(feature = "image-loading", doc, doctest))]
pub fn create_image_from_file_bytes<R: Seek + BufRead>(
&mut self,
data_type: Option<ImageFileFormat>,
smoothing_mode: ImageSmoothingMode,
file_bytes: R
) -> Result<ImageHandle, BacktraceError<ErrorMessage>>
{
self.renderer
.create_image_from_file_bytes(data_type, smoothing_mode, file_bytes)
}
/// Starts the process of drawing a frame. A `Graphics2D` object will be
/// provided to the callback. When the callback returns, the internal
/// render queue will be flushed.
///
/// Note: if calling this method, you are responsible for swapping the
/// window context buffers if necessary.
#[inline]
pub fn draw_frame<F: FnOnce(&mut Graphics2D) -> R, R>(&mut self, callback: F) -> R
{
self.renderer.set_clip(None);
let result = callback(&mut self.renderer);
self.renderer.renderer.finish_frame();
result
}
}
impl Drop for GLRenderer
{
fn drop(&mut self)
{
self.context.mark_invalid();
}
}
/// A `Graphics2D` object allows you to draw shapes, images, and text to the
/// screen.
///
/// An instance is provided in the [window::WindowHandler::on_draw] callback.
///
/// If you are managing the GL context yourself, you must invoke
/// [GLRenderer::draw_frame] to obtain an instance.
pub struct Graphics2D
{
renderer: Renderer2D
}
impl Graphics2D
{
/// Creates a new [ImageHandle] from the specified raw pixel data.
///
/// The data provided in the `data` parameter must be in the format
/// specified by `data_type`.
///
/// The returned [ImageHandle] is valid only for the current graphics
/// context.
pub fn create_image_from_raw_pixels<S: Into<UVec2>>(
&mut self,
data_type: ImageDataType,
smoothing_mode: ImageSmoothingMode,
size: S,
data: &[u8]
) -> Result<ImageHandle, BacktraceError<ErrorMessage>>
{
self.renderer.create_image_from_raw_pixels(
data_type,
smoothing_mode,
size.into(),
data
)
}
/// Loads an image from the specified file path.
///
/// If no `data_type` is provided, an attempt will be made to guess the file
/// format.
///
/// For a list of supported image types, see [image::ImageFileFormat].
///
/// The returned [ImageHandle] is valid only for the current graphics
/// context.
#[cfg(any(feature = "image-loading", doc, doctest))]
pub fn create_image_from_file_path<S: AsRef<Path>>(
&mut self,
data_type: Option<ImageFileFormat>,
smoothing_mode: ImageSmoothingMode,
path: S
) -> Result<ImageHandle, BacktraceError<ErrorMessage>>
{
self.renderer
.create_image_from_file_path(data_type, smoothing_mode, path)
}
/// Loads an image from the provided encoded image file data.
///
/// If no `data_type` is provided, an attempt will be made to guess the file
/// format.
///
/// The data source must implement `std::io::BufRead` and `std::io::Seek`.
/// For example, if you have a `&[u8]`, you may wrap it in a
/// `std::io::Cursor` as follows:
///
/// ```rust,no_run
/// # use speedy2d::GLRenderer;
/// # use speedy2d::color::Color;
/// # use speedy2d::image::ImageSmoothingMode;
/// use std::io::Cursor;
/// # let mut renderer = unsafe {GLRenderer::new_for_current_context((0,0))}.unwrap();
/// # renderer.draw_frame(|graphics| {
///
/// let image_bytes : &[u8] = include_bytes!("../assets/screenshots/hello_world.png");
///
/// let image_result = graphics.create_image_from_file_bytes(
/// None,
/// ImageSmoothingMode::Linear,
/// Cursor::new(image_bytes));
/// # });
/// ```
///
/// For a list of supported image types, see [image::ImageFileFormat].
///
/// The returned [ImageHandle] is valid only for the current graphics
/// context.
#[cfg(any(feature = "image-loading", doc, doctest))]
pub fn create_image_from_file_bytes<R: Seek + BufRead>(
&mut self,
data_type: Option<ImageFileFormat>,
smoothing_mode: ImageSmoothingMode,
file_bytes: R
) -> Result<ImageHandle, BacktraceError<ErrorMessage>>
{
self.renderer
.create_image_from_file_bytes(data_type, smoothing_mode, file_bytes)
}
/// Fills the screen with the specified color.
pub fn clear_screen(&mut self, color: Color)
{
self.renderer.clear_screen(color);
}
/// Draws the provided block of text at the specified position.
///
/// Lines of text can be prepared by loading a font (using
/// [crate::font::Font::new]), and calling `layout_text_line()` on that
/// font with your desired text.
///
/// To fall back to another font if a glyph isn't found, see
/// [crate::font::FontFamily].
///
/// To achieve good performance, it's possible to layout a line of text
/// once, and then re-use the same [crate::font::FormattedTextLine]
/// object whenever you need to draw that text to the screen.
///
/// Note: Text will be rendered with subpixel precision. If the subpixel
/// position changes between frames, performance may be degraded, as the
/// text will need to be re-rendered and re-uploaded. To avoid this,
/// call `round()` on the position coordinates, to ensure that
/// the text is always located at an integer pixel position.
pub fn draw_text<V: Into<Vec2>>(
&mut self,
position: V,
color: Color,
text: &Rc<FormattedTextBlock>
)
{
self.renderer.draw_text(position, color, text);
}
/// Draws the provided block of text at the specified position, cropped to
/// the specified window. Characters outside this window will not be
/// rendered. Characters partially inside the window will be cropped.
///
/// Both `position` and `crop_window` are relative to the overall render
/// window.
///
/// See the documentation for [Graphics2D::draw_text] for more details.
pub fn draw_text_cropped<V: Into<Vec2>>(
&mut self,
position: V,
crop_window: Rect,
color: Color,
text: &Rc<FormattedTextBlock>
)
{
self.renderer
.draw_text_cropped(position, crop_window, color, text);
}
/// Draws a polygon with a single color, with the specified offset in
/// pixels.
pub fn draw_polygon<V: Into<Vec2>>(
&mut self,
polygon: &Polygon,
offset: V,
color: Color
)
{
self.renderer.draw_polygon(polygon, offset, color)
}
/// Draws a triangle with the specified colors (one color for each corner).
///
/// The vertex positions (and associated colors) must be provided in
/// clockwise order.
pub fn draw_triangle_three_color(
&mut self,
vertex_positions_clockwise: [Vec2; 3],
vertex_colors_clockwise: [Color; 3]
)
{
self.renderer.draw_triangle_three_color(
vertex_positions_clockwise,
vertex_colors_clockwise
);
}
/// Draws part of an image, tinted with the provided colors, at the
/// specified location. The sub-image will be scaled to fill the
/// triangle described by the vertices in `vertex_positions_clockwise`.
///
/// The coordinates in `image_coords_normalized` should be in the range
/// `0.0` to `1.0`, and define the portion of the source image which
/// should be drawn.
///
/// The tinting is performed by for each pixel by multiplying each color
/// component in the image pixel by the corresponding color component in
/// the `color` parameter.
///
/// The vertex positions (and associated colors and image coordinates) must
/// be provided in clockwise order.
pub fn draw_triangle_image_tinted_three_color(
&mut self,
vertex_positions_clockwise: [Vec2; 3],
vertex_colors: [Color; 3],
image_coords_normalized: [Vec2; 3],
image: &ImageHandle
)
{
self.renderer.draw_triangle_image_tinted(
vertex_positions_clockwise,
vertex_colors,
image_coords_normalized,
image
);
}
/// Draws a triangle with the specified color.
///
/// The vertex positions must be provided in clockwise order.
#[inline]
pub fn draw_triangle(&mut self, vertex_positions_clockwise: [Vec2; 3], color: Color)
{
self.draw_triangle_three_color(vertex_positions_clockwise, [color, color, color]);
}
/// Draws a quadrilateral with the specified colors (one color for each
/// corner).
///
/// The vertex positions (and associated colors) must be provided in
/// clockwise order.
#[inline]
pub fn draw_quad_four_color(
&mut self,
vertex_positions_clockwise: [Vec2; 4],
vertex_colors: [Color; 4]
)
{
let vp = vertex_positions_clockwise;
let vc = vertex_colors;
self.draw_triangle_three_color([vp[0], vp[1], vp[2]], [vc[0], vc[1], vc[2]]);
self.draw_triangle_three_color([vp[2], vp[3], vp[0]], [vc[2], vc[3], vc[0]]);
}
/// Draws a quadrilateral with the specified color.
///
/// The vertex positions must be provided in clockwise order.
#[inline]
pub fn draw_quad(&mut self, vertex_positions_clockwise: [Vec2; 4], color: Color)
{
self.draw_quad_four_color(
vertex_positions_clockwise,
[color, color, color, color]
);
}
/// Draws part of an image, tinted with the provided colors, at the
/// specified location. The sub-image will be scaled to fill the
/// quadrilateral described by the vertices in
/// `vertex_positions_clockwise`.
///
/// The coordinates in `image_coords_normalized` should be in the range
/// `0.0` to `1.0`, and define the portion of the source image which
/// should be drawn.
///
/// The tinting is performed by for each pixel by multiplying each color
/// component in the image pixel by the corresponding color component in
/// the `color` parameter.
///
/// The vertex positions (and associated colors and image coordinates) must
/// be provided in clockwise order.
#[inline]
pub fn draw_quad_image_tinted_four_color(
&mut self,
vertex_positions_clockwise: [Vec2; 4],
vertex_colors: [Color; 4],
image_coords_normalized: [Vec2; 4],
image: &ImageHandle
)
{
let vp = vertex_positions_clockwise;
let vc = vertex_colors;
let ic = image_coords_normalized;
self.draw_triangle_image_tinted_three_color(
[vp[0], vp[1], vp[2]],
[vc[0], vc[1], vc[2]],
[ic[0], ic[1], ic[2]],
image
);
self.draw_triangle_image_tinted_three_color(
[vp[2], vp[3], vp[0]],
[vc[2], vc[3], vc[0]],
[ic[2], ic[3], ic[0]],
image
);
}
/// Draws part of an image, tinted with the provided color, at the specified
/// location. The sub-image will be scaled to fill the pixel coordinates
/// in the provided rectangle.
///
/// The coordinates in `image_coords_normalized` should be in the range
/// `0.0` to `1.0`, and define the portion of the source image which
/// should be drawn.
///
/// The tinting is performed by for each pixel by multiplying each color
/// component in the image pixel by the corresponding color component in
/// the `color` parameter.
#[inline]
pub fn draw_rectangle_image_subset_tinted(
&mut self,
rect: Rectangle,
color: Color,
image_coords_normalized: Rectangle,
image: &ImageHandle
)
{
self.draw_quad_image_tinted_four_color(
[
*rect.top_left(),
rect.top_right(),
*rect.bottom_right(),
rect.bottom_left()
],
[color, color, color, color],
[
*image_coords_normalized.top_left(),
image_coords_normalized.top_right(),
*image_coords_normalized.bottom_right(),
image_coords_normalized.bottom_left()
],
image
);
}
/// Draws an image, tinted with the provided color, at the specified
/// location. The image will be scaled to fill the pixel coordinates in
/// the provided rectangle.
///
/// The tinting is performed by for each pixel by multiplying each color
/// component in the image pixel by the corresponding color component in
/// the `color` parameter.
#[inline]
pub fn draw_rectangle_image_tinted(
&mut self,
rect: Rectangle,
color: Color,
image: &ImageHandle
)
{
self.draw_rectangle_image_subset_tinted(
rect,
color,
Rectangle::new(Vec2::ZERO, Vec2::new(1.0, 1.0)),
image
);
}
/// Draws an image at the specified location. The image will be
/// scaled to fill the pixel coordinates in the provided rectangle.
#[inline]
pub fn draw_rectangle_image(&mut self, rect: Rectangle, image: &ImageHandle)
{
self.draw_rectangle_image_tinted(rect, Color::WHITE, image);
}
/// Draws an image at the specified pixel location. The image will be
/// drawn at its original size with no scaling.
#[inline]
pub fn draw_image<P: Into<Vec2>>(&mut self, position: P, image: &ImageHandle)
{
let position = position.into();
self.draw_rectangle_image(
Rectangle::new(position, position + image.size().into_f32()),
image
);
}
/// Draws a single-color rectangle at the specified location. The
/// coordinates of the rectangle are specified in pixels.
#[inline]
pub fn draw_rectangle(&mut self, rect: Rectangle, color: Color)
{
self.draw_quad(
[
*rect.top_left(),
rect.top_right(),
*rect.bottom_right(),
rect.bottom_left()
],
color
);
}
/// Draws a single-color line between the given points, specified in pixels.
///
/// # Pixel alignment
///
/// On a display with square pixels, an integer-valued coordinate is located
/// at the boundary between two pixels, rather than the center of the
/// pixel. For example:
///
/// * `(0.0, 0.0)` = Top left of pixel
/// * `(0.5, 0.5)` = Center of pixel
/// * `(1.0, 1.0)` = Bottom right of pixel
///
/// If drawing a line of odd-numbered thickness, it is advisable to locate
/// the start and end of the line at the centers of pixels, rather than
/// the edges.
///
/// For example, a one-pixel-thick line between `(0.0, 10.0)` and `(100.0,
/// 10.0)` will be drawn as a rectangle with corners `(0.0, 9.5)` and
/// `(100.0, 10.5)`, meaning that the line's thickness will actually
/// span two half-pixels. Drawing the same line between `(0.0, 10.5)`
/// and `(100.0, 10.5)` will result in a pixel-aligned rectangle between
/// `(0.0, 10.0)` and `(100.0, 11.0)`.
pub fn draw_line<VStart: Into<Vec2>, VEnd: Into<Vec2>>(
&mut self,
start_position: VStart,
end_position: VEnd,
thickness: f32,
color: Color
)
{
let start_position = start_position.into();
let end_position = end_position.into();
let gradient_normalized = match (end_position - start_position).normalize() {
None => return,
Some(gradient) => gradient
};
let gradient_thickness = gradient_normalized * (thickness / 2.0);
let offset_anticlockwise = gradient_thickness.rotate_90_degrees_anticlockwise();
let offset_clockwise = gradient_thickness.rotate_90_degrees_clockwise();
let start_anticlockwise = start_position + offset_anticlockwise;
let start_clockwise = start_position + offset_clockwise;
let end_anticlockwise = end_position + offset_anticlockwise;
let end_clockwise = end_position + offset_clockwise;
self.draw_quad(
[
start_anticlockwise,
end_anticlockwise,
end_clockwise,
start_clockwise
],
color
);
}
/// Draws a circle, filled with a single color, at the specified pixel
/// location.
pub fn draw_circle<V: Into<Vec2>>(
&mut self,
center_position: V,
radius: f32,
color: Color
)
{
let center_position = center_position.into();
let top_left = center_position + Vec2::new(-radius, -radius);
let top_right = center_position + Vec2::new(radius, -radius);
let bottom_right = center_position + Vec2::new(radius, radius);
let bottom_left = center_position + Vec2::new(-radius, radius);
self.renderer.draw_circle_section(
[top_left, top_right, bottom_right],
[color, color, color],
[
Vec2::new(-1.0, -1.0),
Vec2::new(1.0, -1.0),
Vec2::new(1.0, 1.0)
]
);
self.renderer.draw_circle_section(
[bottom_right, bottom_left, top_left],
[color, color, color],
[
Vec2::new(1.0, 1.0),
Vec2::new(-1.0, 1.0),
Vec2::new(-1.0, -1.0)
]
);
}
/// Draws a triangular subset of a circle.
///
/// Put simply, this function will draw a triangle on the screen, textured
/// with a region of a circle.
///
/// The circle region is specified using `vertex_circle_coords_normalized`,
/// which denotes UV coordinates relative to an infinitely-detailed
/// circle of radius `1.0`, and center `(0.0, 0.0)`.
///
/// For example, to draw the top-right half of a circle with radius 100px:
///
/// ```rust,no_run
/// # use speedy2d::GLRenderer;
/// # use speedy2d::dimen::Vec2;
/// # use speedy2d::color::Color;
/// # let mut renderer = unsafe {GLRenderer::new_for_current_context((0,0))}.unwrap();
/// # renderer.draw_frame(|graphics| {
/// graphics.draw_circle_section_triangular_three_color(
/// [
/// Vec2::new(200.0, 200.0),
/// Vec2::new(300.0, 200.0),
/// Vec2::new(300.0, 300.0)],
/// [Color::MAGENTA; 3],
/// [
/// Vec2::new(-1.0, -1.0),
/// Vec2::new(1.0, -1.0),
/// Vec2::new(1.0, 1.0)]);
/// # });
/// ```
#[inline]
pub fn draw_circle_section_triangular_three_color(
&mut self,
vertex_positions_clockwise: [Vec2; 3],
vertex_colors: [Color; 3],
vertex_circle_coords_normalized: [Vec2; 3]
)
{
self.renderer.draw_circle_section(
vertex_positions_clockwise,
vertex_colors,
vertex_circle_coords_normalized
);
}
/// Sets the current clip to the rectangle specified by the given
/// coordinates. Rendering operations have no effect outside of the
/// clipping area.
pub fn set_clip(&mut self, rect: Option<Rectangle<i32>>)
{
self.renderer.set_clip(rect);
}
/// Captures a screenshot of the render window. The returned data contains
/// the color of each pixel. Pixels are represented using a `u8` for each
/// component (red, green, blue, and alpha). Use the `format` parameter to
/// specify the byte layout (and size) of each pixel.
pub fn capture(&mut self, format: ImageDataType) -> RawBitmapData
{
self.renderer.capture(format)
}
}
/// Struct representing a window.
#[cfg(any(doc, doctest, all(feature = "windowing", not(target_arch = "wasm32"))))]
pub struct Window<UserEventType = ()>
where
UserEventType: 'static
{
window_impl: WindowGlutin<UserEventType>,
renderer: GLRenderer
}
#[cfg(any(doc, doctest, all(feature = "windowing", not(target_arch = "wasm32"))))]
impl Window<()>
{
/// Create a new window, centered in the middle of the primary monitor.
pub fn new_centered<Str, Size>(
title: Str,
size: Size
) -> Result<Window<()>, BacktraceError<WindowCreationError>>
where
Str: AsRef<str>,
Size: Into<UVec2>
{
let size = size.into();
Self::new_with_options(
title.as_ref(),
WindowCreationOptions::new_windowed(
WindowSize::PhysicalPixels(size),
Some(WindowPosition::Center)
)
)
}
/// Create a new window, in fullscreen borderless mode on the primary
/// monitor.
pub fn new_fullscreen_borderless<Str>(
title: Str
) -> Result<Window<()>, BacktraceError<WindowCreationError>>
where
Str: AsRef<str>
{
Self::new_with_options(
title.as_ref(),
WindowCreationOptions::new_fullscreen_borderless()
)
}
/// Create a new window with the specified options.
pub fn new_with_options(
title: &str,
options: WindowCreationOptions
) -> Result<Window<()>, BacktraceError<WindowCreationError>>
{
Self::new_with_user_events(title, options)
}
}
#[cfg(any(doc, doctest, all(feature = "windowing", not(target_arch = "wasm32"))))]
impl<UserEventType: 'static> Window<UserEventType>
{
/// Create a new window with the specified options, with support for user
/// events. See [window::UserEventSender].
pub fn new_with_user_events(
title: &str,
options: WindowCreationOptions
) -> Result<Self, BacktraceError<WindowCreationError>>
{
let window_impl = WindowGlutin::new(title, options)?;
let renderer = GLRenderer::new_with_gl_backend(
window_impl.get_inner_size_pixels(),
window_impl.gl_backend().clone(),
GLVersion::OpenGL2_0
)
.map_err(|err| {
BacktraceError::new_with_cause(
WindowCreationError::RendererCreationFailed,
err
)
})?;
Ok(Window {
window_impl,
renderer
})
}
/// Creates a [window::UserEventSender], which can be used to post custom
/// events to this event loop from another thread.
///
/// If calling this, specify the type of the event data using
/// `Window::<YourTypeHere>::new_with_user_events()`.
///
/// See [UserEventSender::send_event], [WindowHandler::on_user_event].
pub fn create_user_event_sender(&self) -> UserEventSender<UserEventType>
{
self.window_impl.create_user_event_sender()
}
/// Run the window event loop, with the specified callback handler.
///
/// Once the event loop finishes running, the entire app will terminate,
/// even if other threads are still running. See
/// [window::WindowHelper::terminate_loop()].
pub fn run_loop<H>(self, handler: H) -> !
where
H: WindowHandler<UserEventType> + 'static
{
self.window_impl.run_loop(handler, self.renderer);
}
}
/// Struct representing an HTML canvas.
#[cfg(any(doc, doctest, all(target_arch = "wasm32", feature = "windowing")))]
pub struct WebCanvas<UserEventType = ()>
where
UserEventType: 'static
{
inner: Option<WebCanvasImpl>,
should_cleanup: bool,
user_event_type: PhantomData<UserEventType>
}
#[cfg(any(doc, doctest, all(target_arch = "wasm32", feature = "windowing")))]
impl WebCanvas<()>
{
/// Creates (and starts running) a new WebCanvas instance, attached to the
/// HTML canvas with the specified ID. Event handlers will be registered for
/// keyboard, mouse, and other events.
///
/// The event loop/handlers will continue to exist after the WebCanvas is
/// dropped. This behaviour can be avoided using
/// [WebCanvas::unregister_when_dropped].
///
/// The provided [WindowHandler] will start to receive callbacks as soon as
/// this function returns. Note that the main thread must not be blocked.
pub fn new_for_id<S, H>(
element_id: S,
handler: H
) -> Result<WebCanvas<()>, BacktraceError<ErrorMessage>>
where
S: AsRef<str>,
H: WindowHandler<()> + 'static
{
WebCanvas::<()>::new_for_id_with_user_events(element_id, handler)
}
}
#[cfg(any(doc, doctest, all(target_arch = "wasm32", feature = "windowing")))]
impl<UserEventType: 'static> WebCanvas<UserEventType>
{
/// Creates (and starts running) a new WebCanvas instance, attached to the
/// HTML canvas with the specified ID. Event handlers will be registered for
/// keyboard, mouse, and other events.
///
/// This variant has support for user-generated events. See
/// [window::UserEventSender] for more details.
///
/// The event loop/handlers will continue to exist after the WebCanvas is
/// dropped. This behaviour can be avoided using
/// [WebCanvas::unregister_when_dropped].
///
/// The provided [WindowHandler] will start to receive callbacks as soon as
/// this function returns. Note that the main thread must not be blocked.
pub fn new_for_id_with_user_events<S, H>(
element_id: S,
handler: H
) -> Result<Self, BacktraceError<ErrorMessage>>
where
S: AsRef<str>,
H: WindowHandler<UserEventType> + 'static
{
Ok(WebCanvas {
inner: Some(WebCanvasImpl::new(element_id, handler)?),
should_cleanup: false,
user_event_type: PhantomData::default()
})
}
/// Causes the WebCanvas event loop to terminate when the WebCanvas is
/// dropped. If this function is not called, then the event loop (and
/// associated event handlers) will continue to run after the WebCanvas
/// struct is dropped.
pub fn unregister_when_dropped(&mut self)
{
self.should_cleanup = true;
}
}
#[cfg(any(doc, doctest, all(target_arch = "wasm32", feature = "windowing")))]
impl<UserEventType: 'static> Drop for WebCanvas<UserEventType>
{
fn drop(&mut self)
{
if !self.should_cleanup {
std::mem::forget(self.inner.take());
log::info!(
"Deliberately leaking speedy2d::WebCanvas object. This is normally \
fine, but if you want to clean up before the page closes, call \
WebCanvas::unregister_when_dropped(), and retain ownership of the \
WebCanvas until you want to delete it."
)
}
}
}