slint/sixtyfps_runtime/corelib/graphics.rs
Simon Hausmann 65dcb2cb33 Merge BuiltinItem and GeneratePropertyAccessors derive macros
... into the new SixtyFPSElement macro. This generates getters for all properties.
2021-01-14 08:53:13 +01:00

704 lines
24 KiB
Rust

/* LICENSE BEGIN
This file is part of the SixtyFPS Project -- https://sixtyfps.io
Copyright (c) 2020 Olivier Goffart <olivier.goffart@sixtyfps.io>
Copyright (c) 2020 Simon Hausmann <simon.hausmann@sixtyfps.io>
SPDX-License-Identifier: GPL-3.0-only
This file is also available under commercial licensing terms.
Please contact info@sixtyfps.io for more information.
LICENSE END */
#![warn(missing_docs)]
/*!
Graphics Abstractions.
This module contains the abstractions and convenience types to allow the runtime
library to instruct different graphics backends to render the tree of items.
The entry trait is [GraphicsBackend].
The run-time library also makes use of [RenderingCache] to store the rendering primitives
created by the backend in a type-erased manner.
*/
extern crate alloc;
use crate::item_rendering::CachedRenderingData;
use crate::properties::InterpolatedPropertyValue;
#[cfg(feature = "rtti")]
use crate::rtti::{BuiltinItem, FieldInfo, PropertyInfo, ValueType};
use crate::{Callback, SharedString};
use auto_enums::auto_enum;
use const_field_offset::FieldOffsets;
use sixtyfps_corelib_macros::*;
use std::{cell::RefCell, rc::Rc};
/// 2D Rectangle
pub type Rect = euclid::default::Rect<f32>;
/// 2D Rectangle with integer coordinates
pub type IntRect = euclid::default::Rect<i32>;
/// 2D Point
pub type Point = euclid::default::Point2D<f32>;
/// 2D Size
pub type Size = euclid::default::Size2D<f32>;
/// RgbaColor stores the red, green, blue and alpha components of a color
/// with the precision of the generic parameter T. For example if T is f32,
/// the values are normalized between 0 and 1. If T is u8, they values range
/// is 0 to 255.
/// This is merely a helper class for use with [`Color`].
#[derive(Copy, Clone, PartialEq, Debug, Default)]
pub struct RgbaColor<T> {
/// The alpha component.
pub alpha: T,
/// The red channel.
pub red: T,
/// The green channel.
pub green: T,
/// The blue channel.
pub blue: T,
}
/// Color represents a color in the SixtyFPS run-time, represented using 8-bit channels for
/// red, green, blue and the alpha (opacity).
/// It can be conveniently constructed and destructured using the to_ and from_ (a)rgb helper functions:
/// ```
/// # fn do_something_with_red_and_green(_:f32, _:f32) {}
/// # fn do_something_with_red(_:u8) {}
/// # use sixtyfps_corelib::graphics::{Color, RgbaColor};
/// # let some_color = Color::from_rgb_u8(0, 0, 0);
/// let col = some_color.to_argb_f32();
/// do_something_with_red_and_green(col.red, col.green);
///
/// let RgbaColor { red, blue, green, .. } = some_color.to_argb_u8();
/// do_something_with_red(red);
///
/// let new_col = Color::from(RgbaColor{ red: 0.5, green: 0.65, blue: 0.32, alpha: 1.});
/// ```
#[derive(Copy, Clone, PartialEq, Debug, Default)]
#[repr(C)]
pub struct Color {
red: u8,
green: u8,
blue: u8,
alpha: u8,
}
impl From<RgbaColor<u8>> for Color {
fn from(col: RgbaColor<u8>) -> Self {
Self { red: col.red, green: col.green, blue: col.blue, alpha: col.alpha }
}
}
impl From<Color> for RgbaColor<u8> {
fn from(col: Color) -> Self {
RgbaColor { red: col.red, green: col.green, blue: col.blue, alpha: col.alpha }
}
}
impl From<RgbaColor<u8>> for RgbaColor<f32> {
fn from(col: RgbaColor<u8>) -> Self {
Self {
red: (col.red as f32) / 255.0,
green: (col.green as f32) / 255.0,
blue: (col.blue as f32) / 255.0,
alpha: (col.alpha as f32) / 255.0,
}
}
}
impl From<Color> for RgbaColor<f32> {
fn from(col: Color) -> Self {
let u8col: RgbaColor<u8> = col.into();
u8col.into()
}
}
impl From<RgbaColor<f32>> for Color {
fn from(col: RgbaColor<f32>) -> Self {
Self {
red: (col.red * 255.) as u8,
green: (col.green * 255.) as u8,
blue: (col.blue * 255.) as u8,
alpha: (col.alpha * 255.) as u8,
}
}
}
impl Color {
/// Construct a color from an integer encoded as `0xAARRGGBB`
pub const fn from_argb_encoded(encoded: u32) -> Color {
Self {
red: (encoded >> 16) as u8,
green: (encoded >> 8) as u8,
blue: encoded as u8,
alpha: (encoded >> 24) as u8,
}
}
/// Returns `(alpha, red, green, blue)` encoded as u32
pub fn as_argb_encoded(&self) -> u32 {
((self.red as u32) << 16)
| ((self.green as u32) << 8)
| (self.blue as u32)
| ((self.alpha as u32) << 24)
}
/// Construct a color from the alpha, red, green and blue color channel parameters.
pub fn from_argb_u8(alpha: u8, red: u8, green: u8, blue: u8) -> Self {
Self { red, green, blue, alpha }
}
/// Construct a color from the red, green and blue color channel parameters. The alpha
/// channel will have the value 255.
pub fn from_rgb_u8(red: u8, green: u8, blue: u8) -> Self {
Self::from_argb_u8(255, red, green, blue)
}
/// Construct a color from the alpha, red, green and blue color channel parameters.
pub fn from_argb_f32(alpha: f32, red: f32, green: f32, blue: f32) -> Self {
RgbaColor { alpha, red, green, blue }.into()
}
/// Construct a color from the red, green and blue color channel parameters. The alpha
/// channel will have the value 255.
pub fn from_rgb_f32(red: f32, green: f32, blue: f32) -> Self {
Self::from_argb_f32(1.0, red, green, blue)
}
/// Converts this color to an RgbaColor struct for easy destructuring.
pub fn to_argb_u8(&self) -> RgbaColor<u8> {
RgbaColor::from(*self)
}
/// Converts this color to an RgbaColor struct for easy destructuring.
pub fn to_argb_f32(&self) -> RgbaColor<f32> {
RgbaColor::from(*self)
}
/// Returns the red channel of the color as u8 in the range 0..255.
pub fn red(self) -> u8 {
self.red
}
/// Returns the green channel of the color as u8 in the range 0..255.
pub fn green(self) -> u8 {
self.green
}
/// Returns the blue channel of the color as u8 in the range 0..255.
pub fn blue(self) -> u8 {
self.blue
}
/// Returns the alpha channel of the color as u8 in the range 0..255.
pub fn alpha(self) -> u8 {
self.alpha
}
}
impl InterpolatedPropertyValue for Color {
fn interpolate(self, target_value: Self, t: f32) -> Self {
Self {
red: self.red.interpolate(target_value.red, t),
green: self.green.interpolate(target_value.green, t),
blue: self.blue.interpolate(target_value.blue, t),
alpha: self.alpha.interpolate(target_value.alpha, t),
}
}
}
impl std::fmt::Display for Color {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "argb({}, {}, {}, {})", self.alpha, self.red, self.green, self.blue)
}
}
#[cfg(feature = "femtovg_backend")]
impl From<&Color> for femtovg::Color {
fn from(col: &Color) -> Self {
Self::rgba(col.red, col.green, col.blue, col.alpha)
}
}
#[cfg(feature = "femtovg_backend")]
impl From<Color> for femtovg::Color {
fn from(col: Color) -> Self {
Self::rgba(col.red, col.green, col.blue, col.alpha)
}
}
/// A resource is a reference to binary data, for example images. They can be accessible on the file
/// system or embedded in the resulting binary. Or they might be URLs to a web server and a downloaded
/// is necessary before they can be used.
#[derive(Clone, PartialEq, Debug)]
#[repr(u8)]
pub enum Resource {
/// A resource that does not represent any data.
None,
/// A resource that points to a file in the file system
AbsoluteFilePath(crate::SharedString),
/// A resource that is embedded in the program and accessible via pointer
/// The format is the same as in a file
EmbeddedData(super::slice::Slice<'static, u8>),
/// Raw ARGB
#[allow(missing_docs)]
EmbeddedRgbaImage { width: u32, height: u32, data: super::sharedvector::SharedVector<u32> },
}
impl Default for Resource {
fn default() -> Self {
Resource::None
}
}
pub struct CachedGraphicsData<T> {
pub data: T,
/// The property tracker that should be used to evaluate whether the primitive needs to be re-created
/// or not.
pub dependency_tracker: core::pin::Pin<Box<crate::properties::PropertyTracker>>,
}
impl<T> CachedGraphicsData<T> {
/// Creates a new TrackingRenderingPrimitive by evaluating the provided update_fn once, storing the returned
/// rendering primitive and initializing the dependency tracker.
pub fn new(update_fn: impl FnOnce() -> T) -> Self {
let dependency_tracker = Box::pin(crate::properties::PropertyTracker::default());
let data = dependency_tracker.as_ref().evaluate(update_fn);
Self { data, dependency_tracker }
}
}
pub type RenderingCache<T> = vec_arena::Arena<CachedGraphicsData<T>>;
/// FontRequest collects all the developer-configurable properties for fonts, such as family, weight, etc.
/// It is submitted as a request to the platform font system (i.e. CoreText on macOS) and in exchange we
/// store a Rc<FontHandle>
#[derive(Debug, Clone, PartialEq)]
#[repr(C)]
pub struct FontRequest {
pub family: SharedString,
pub weight: i32,
}
pub trait Font {
fn text_width(&self, pixel_size: f32, text: &str) -> f32;
fn text_offset_for_x_position<'a>(&self, pixel_size: f32, text: &'a str, x: f32) -> usize;
fn height(&self, pixel_size: f32) -> f32;
}
pub struct ScaledFont {
pub font: Rc<dyn Font>,
pub pixel_size: f32,
}
impl ScaledFont {
pub(crate) fn text_width(&self, text: &str) -> f32 {
self.font.text_width(self.pixel_size, text)
}
pub(crate) fn text_offset_for_x_position<'a>(&self, text: &'a str, x: f32) -> usize {
self.font.text_offset_for_x_position(self.pixel_size, text, x)
}
pub(crate) fn height(&self) -> f32 {
self.font.height(self.pixel_size)
}
}
/// GraphicsBackend is the trait that the the SixtyFPS run-time uses to convert [HighLevelRenderingPrimitive]
/// to an internal representation that is optimal for the backend, in order to render it later. The internal
/// representation is opaque but must be provided via the [GraphicsBackend::LowLevelRenderingPrimitive] associated type.
///
/// The backend operates in two modes:
/// 1. It can be used to create new rendering primitives, by calling [GraphicsBackend::new_rendering_primitives_builder]. This is
/// usually an expensive step, that involves uploading data to the GPU or performing other pre-calculations.
///
/// 1. A series of low-level rendering primitives can be rendered into a frame, that's started using [GraphicsBackend::new_frame].
/// The low-level rendering primitives are intended to be fast and ready for rendering.
pub trait GraphicsBackend: Sized {
type ItemRenderer: crate::item_rendering::ItemRenderer;
fn new_renderer(&mut self, clear_color: &Color) -> Self::ItemRenderer;
fn flush_renderer(&mut self, renderer: Self::ItemRenderer);
fn release_item_graphics_cache(&self, data: &CachedRenderingData);
fn font(&mut self, request: FontRequest) -> Rc<dyn Font>;
/// Returns the window that the backend is associated with.
fn window(&self) -> &winit::window::Window;
}
#[repr(C)]
#[derive(FieldOffsets, Default, SixtyFPSElement, Clone, Debug, PartialEq)]
#[pin]
/// PathLineTo describes the event of moving the cursor on the path to the specified location
/// along a straight line.
pub struct PathLineTo {
#[rtti_field]
/// The x coordinate where the line should go to.
pub x: f32,
#[rtti_field]
/// The y coordinate where the line should go to.
pub y: f32,
}
#[repr(C)]
#[derive(FieldOffsets, Default, SixtyFPSElement, Clone, Debug, PartialEq)]
#[pin]
/// PathArcTo describes the event of moving the cursor on the path across an arc to the specified
/// x/y coordinates, with the specified x/y radius and additional properties.
pub struct PathArcTo {
#[rtti_field]
/// The x coordinate where the arc should end up.
pub x: f32,
#[rtti_field]
/// The y coordinate where the arc should end up.
pub y: f32,
#[rtti_field]
/// The radius on the x-axis of the arc.
pub radius_x: f32,
#[rtti_field]
/// The radius on the y-axis of the arc.
pub radius_y: f32,
#[rtti_field]
/// The rotation along the x-axis of the arc in degress.
pub x_rotation: f32,
#[rtti_field]
/// large_arc indicates whether to take the long or the shorter path to complete the arc.
pub large_arc: bool,
#[rtti_field]
/// sweep indicates the direction of the arc. If true, a clockwise direction is chosen,
/// otherwise counter-clockwise.
pub sweep: bool,
}
#[repr(C)]
#[derive(Clone, Debug, PartialEq)]
/// PathElement describes a single element on a path, such as move-to, line-to, etc.
pub enum PathElement {
/// The LineTo variant describes a line.
LineTo(PathLineTo),
/// The PathArcTo variant describes an arc.
ArcTo(PathArcTo),
/// Indicates that the path should be closed now by connecting to the starting point.
Close,
}
#[repr(C)]
#[derive(Clone, Debug, PartialEq)]
/// PathEvent is a low-level data structure describing the composition of a path. Typically it is
/// generated at compile time from a higher-level description, such as SVG commands.
pub enum PathEvent {
/// The beginning of the path.
Begin,
/// A straight line on the path.
Line,
/// A quadratic bezier curve on the path.
Quadratic,
/// A cubic bezier curve on the path.
Cubic,
/// The end of the path that remains open.
EndOpen,
/// The end of a path that is closed.
EndClosed,
}
struct ToLyonPathEventIterator<'a> {
events_it: std::slice::Iter<'a, PathEvent>,
coordinates_it: std::slice::Iter<'a, Point>,
first: Option<&'a Point>,
last: Option<&'a Point>,
}
impl<'a> Iterator for ToLyonPathEventIterator<'a> {
type Item = lyon::path::Event<lyon::math::Point, lyon::math::Point>;
fn next(&mut self) -> Option<Self::Item> {
use lyon::path::Event;
self.events_it.next().map(|event| match event {
PathEvent::Begin => Event::Begin { at: self.coordinates_it.next().unwrap().clone() },
PathEvent::Line => Event::Line {
from: self.coordinates_it.next().unwrap().clone(),
to: self.coordinates_it.next().unwrap().clone(),
},
PathEvent::Quadratic => Event::Quadratic {
from: self.coordinates_it.next().unwrap().clone(),
ctrl: self.coordinates_it.next().unwrap().clone(),
to: self.coordinates_it.next().unwrap().clone(),
},
PathEvent::Cubic => Event::Cubic {
from: self.coordinates_it.next().unwrap().clone(),
ctrl1: self.coordinates_it.next().unwrap().clone(),
ctrl2: self.coordinates_it.next().unwrap().clone(),
to: self.coordinates_it.next().unwrap().clone(),
},
PathEvent::EndOpen => Event::End {
first: self.first.unwrap().clone(),
last: self.last.unwrap().clone(),
close: false,
},
PathEvent::EndClosed => Event::End {
first: self.first.unwrap().clone(),
last: self.last.unwrap().clone(),
close: true,
},
})
}
fn size_hint(&self) -> (usize, Option<usize>) {
self.events_it.size_hint()
}
}
impl<'a> ExactSizeIterator for ToLyonPathEventIterator<'a> {}
struct TransformedLyonPathIterator<EventIt> {
it: EventIt,
transform: lyon::math::Transform,
}
impl<EventIt: Iterator<Item = lyon::path::Event<lyon::math::Point, lyon::math::Point>>> Iterator
for TransformedLyonPathIterator<EventIt>
{
type Item = lyon::path::Event<lyon::math::Point, lyon::math::Point>;
fn next(&mut self) -> Option<Self::Item> {
self.it.next().map(|ev| ev.transformed(&self.transform))
}
fn size_hint(&self) -> (usize, Option<usize>) {
self.it.size_hint()
}
}
impl<EventIt: Iterator<Item = lyon::path::Event<lyon::math::Point, lyon::math::Point>>>
ExactSizeIterator for TransformedLyonPathIterator<EventIt>
{
}
/// PathDataIterator is a data structure that acts as starting point for iterating
/// through the low-level events of a path. If the path was constructed from said
/// events, then it is a very thin abstraction. If the path was created from higher-level
/// elements, then an intermediate lyon path is required/built.
pub struct PathDataIterator<'a> {
it: LyonPathIteratorVariant<'a>,
transform: Option<lyon::math::Transform>,
}
enum LyonPathIteratorVariant<'a> {
FromPath(lyon::path::Path),
FromEvents(&'a crate::SharedVector<PathEvent>, &'a crate::SharedVector<Point>),
}
impl<'a> PathDataIterator<'a> {
/// Create a new iterator for path traversal.
#[auto_enum(Iterator)]
pub fn iter(
&'a self,
) -> impl Iterator<Item = lyon::path::Event<lyon::math::Point, lyon::math::Point>> + 'a {
match &self.it {
LyonPathIteratorVariant::FromPath(path) => self.apply_transform(path.iter()),
LyonPathIteratorVariant::FromEvents(events, coordinates) => {
self.apply_transform(ToLyonPathEventIterator {
events_it: events.iter(),
coordinates_it: coordinates.iter(),
first: coordinates.first(),
last: coordinates.last(),
})
}
}
}
fn fit(&mut self, width: f32, height: f32) {
if width > 0. || height > 0. {
let br = lyon::algorithms::aabb::bounding_rect(self.iter());
self.transform = Some(lyon::algorithms::fit::fit_rectangle(
&br,
&Rect::from_size(Size::new(width, height)),
lyon::algorithms::fit::FitStyle::Min,
));
}
}
#[auto_enum(Iterator)]
fn apply_transform(
&'a self,
event_it: impl Iterator<Item = lyon::path::Event<lyon::math::Point, lyon::math::Point>> + 'a,
) -> impl Iterator<Item = lyon::path::Event<lyon::math::Point, lyon::math::Point>> + 'a {
match self.transform {
Some(transform) => TransformedLyonPathIterator { it: event_it, transform },
None => event_it,
}
}
}
#[repr(C)]
#[derive(Clone, Debug, PartialEq)]
/// PathData represents a path described by either high-level elements or low-level
/// events and coordinates.
pub enum PathData {
/// None is the variant when the path is empty.
None,
/// The Elements variant is used to make a Path from shared arrays of elements.
Elements(crate::SharedVector<PathElement>),
/// The Events variant describes the path as a series of low-level events and
/// associated coordinates.
Events(crate::SharedVector<PathEvent>, crate::SharedVector<Point>),
}
impl Default for PathData {
fn default() -> Self {
Self::None
}
}
impl PathData {
/// This function returns an iterator that allows traversing the path by means of lyon events.
pub fn iter(&self) -> PathDataIterator {
PathDataIterator {
it: match self {
PathData::None => LyonPathIteratorVariant::FromPath(lyon::path::Path::new()),
PathData::Elements(elements) => LyonPathIteratorVariant::FromPath(
PathData::build_path(elements.as_slice().iter()),
),
PathData::Events(events, coordinates) => {
LyonPathIteratorVariant::FromEvents(events, coordinates)
}
},
transform: None,
}
}
/// This function returns an iterator that allows traversing the path by means of lyon events.
pub fn iter_fitted(&self, width: f32, height: f32) -> PathDataIterator {
let mut it = self.iter();
it.fit(width, height);
it
}
fn build_path(element_it: std::slice::Iter<PathElement>) -> lyon::path::Path {
use lyon::geom::SvgArc;
use lyon::math::{Angle, Point, Vector};
use lyon::path::{
builder::{Build, FlatPathBuilder, SvgBuilder},
ArcFlags,
};
let mut path_builder = lyon::path::Path::builder().with_svg();
for element in element_it {
match element {
PathElement::LineTo(PathLineTo { x, y }) => {
path_builder.line_to(Point::new(*x, *y))
}
PathElement::ArcTo(PathArcTo {
x,
y,
radius_x,
radius_y,
x_rotation,
large_arc,
sweep,
}) => {
let radii = Vector::new(*radius_x, *radius_y);
let x_rotation = Angle::degrees(*x_rotation);
let flags = ArcFlags { large_arc: *large_arc, sweep: *sweep };
let to = Point::new(*x, *y);
let svg_arc = SvgArc {
from: path_builder.current_position(),
radii,
x_rotation,
flags,
to,
};
if svg_arc.is_straight_line() {
path_builder.line_to(to);
} else {
path_builder.arc_to(radii, x_rotation, flags, to)
}
}
PathElement::Close => path_builder.close(),
}
}
path_builder.build()
}
}
pub(crate) mod ffi {
#![allow(unsafe_code)]
use super::*;
#[allow(non_camel_case_types)]
type c_void = ();
/// Expand Rect so that cbindgen can see it. ( is in fact euclid::default::Rect<f32>)
#[cfg(cbindgen)]
#[repr(C)]
struct Rect {
x: f32,
y: f32,
width: f32,
height: f32,
}
/// Expand IntRect so that cbindgen can see it. ( is in fact euclid::default::Rect<i32>)
#[cfg(cbindgen)]
#[repr(C)]
struct IntRect {
x: i32,
y: i32,
width: i32,
height: i32,
}
/// Expand Point so that cbindgen can see it. ( is in fact euclid::default::PointD2<f32>)
#[cfg(cbindgen)]
#[repr(C)]
struct Point {
x: f32,
y: f32,
}
#[no_mangle]
/// This function is used for the low-level C++ interface to allocate the backing vector for a shared path element array.
pub unsafe extern "C" fn sixtyfps_new_path_elements(
out: *mut c_void,
first_element: *const PathElement,
count: usize,
) {
let arr = crate::SharedVector::from(std::slice::from_raw_parts(first_element, count));
core::ptr::write(out as *mut crate::SharedVector<PathElement>, arr.clone());
}
#[no_mangle]
/// This function is used for the low-level C++ interface to allocate the backing vector for a shared path event array.
pub unsafe extern "C" fn sixtyfps_new_path_events(
out_events: *mut c_void,
out_coordinates: *mut c_void,
first_event: *const PathEvent,
event_count: usize,
first_coordinate: *const Point,
coordinate_count: usize,
) {
let events =
crate::SharedVector::from(std::slice::from_raw_parts(first_event, event_count));
core::ptr::write(out_events as *mut crate::SharedVector<PathEvent>, events.clone());
let coordinates = crate::SharedVector::from(std::slice::from_raw_parts(
first_coordinate,
coordinate_count,
));
core::ptr::write(out_coordinates as *mut crate::SharedVector<Point>, coordinates.clone());
}
}
thread_local! {
/// Database used to keep track of fonts added by the application
pub static APPLICATION_FONTS: RefCell<fontdb::Database> = RefCell::new(fontdb::Database::new())
}
/// This function can be used to register a custom TrueType font with SixtyFPS,
/// for use with the `font-family` property. The provided slice must be a valid TrueType
/// font.
pub fn register_application_font_from_memory(
data: &'static [u8],
) -> Result<(), Box<dyn std::error::Error>> {
APPLICATION_FONTS.with(|fontdb| fontdb.borrow_mut().load_font_data(data.into()));
Ok(())
}