From 0240c3981b716c82ecb3364945815335b420a63e Mon Sep 17 00:00:00 2001 From: Héctor Ramón Jiménez Date: Sun, 10 Nov 2019 06:05:20 +0100 Subject: Draft custom layout engine based on `druid` --- native/src/layout/flex.rs | 155 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 155 insertions(+) create mode 100644 native/src/layout/flex.rs (limited to 'native/src/layout/flex.rs') diff --git a/native/src/layout/flex.rs b/native/src/layout/flex.rs new file mode 100644 index 00000000..98cc344e --- /dev/null +++ b/native/src/layout/flex.rs @@ -0,0 +1,155 @@ +// This code is heavily inspired by the [`druid`] codebase. +// +// [`druid`]: https://github.com/xi-editor/druid +// +// Copyright 2018 The xi-editor Authors, Héctor Ramón +// +// 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. +use crate::{ + layout::{Limits, Node}, + Element, Size, +}; + +#[derive(Debug)] +pub enum Axis { + Horizontal, + Vertical, +} + +impl Axis { + fn main(&self, size: Size) -> f32 { + match self { + Axis::Horizontal => size.width, + Axis::Vertical => size.height, + } + } + + fn cross(&self, size: Size) -> f32 { + match self { + Axis::Horizontal => size.height, + Axis::Vertical => size.width, + } + } + + fn pack(&self, main: f32, cross: f32) -> (f32, f32) { + match self { + Axis::Horizontal => (main, cross), + Axis::Vertical => (cross, main), + } + } +} + +// TODO: Remove `Message` type parameter +pub fn resolve( + axis: Axis, + renderer: &Renderer, + limits: &Limits, + padding: f32, + spacing: f32, + children: &[Element<'_, Message, Renderer>], +) -> Node +where + Renderer: crate::Renderer, +{ + let limits = limits.pad(padding); + + let mut total_non_fill = spacing as f32 * (children.len() - 1) as f32; + let mut fill_sum = 0; + + let mut nodes: Vec = Vec::with_capacity(children.len()); + nodes.resize(children.len(), Node::default()); + + for (i, child) in children.iter().enumerate() { + let fill_factor = match axis { + Axis::Horizontal => child.width(), + Axis::Vertical => child.height(), + } + .fill_factor(); + + if fill_factor == 0 { + let child_limits = Limits::new(Size::ZERO, limits.max()); + + let layout = child.layout(renderer, &child_limits); + + total_non_fill += axis.main(layout.size()); + + nodes[i] = layout; + } else { + fill_sum += fill_factor; + } + } + + let available = axis.main(limits.max()); + let remaining = (available - total_non_fill).max(0.0); + + for (i, child) in children.iter().enumerate() { + let fill_factor = match axis { + Axis::Horizontal => child.width(), + Axis::Vertical => child.height(), + } + .fill_factor(); + + if fill_factor != 0 { + let max_main = remaining * fill_factor as f32 / fill_sum as f32; + let min_main = if max_main.is_infinite() { + 0.0 + } else { + max_main + }; + + let (min_main, min_cross) = + axis.pack(min_main, axis.cross(limits.min())); + + let (max_main, max_cross) = + axis.pack(max_main, axis.cross(limits.max())); + + let child_limits = Limits::new( + Size::new(min_main, min_cross), + Size::new(max_main, max_cross), + ); + + let layout = child.layout(renderer, &child_limits); + + nodes[i] = layout; + } + } + + let mut main = padding; + let mut cross = axis.cross(limits.min()); + + for (i, node) in nodes.iter_mut().enumerate() { + if i > 0 { + main += spacing; + } + + let (x, y) = axis.pack(main, padding); + + node.bounds.x = x; + node.bounds.y = y; + + let size = node.size(); + + main += axis.main(size); + cross = cross.max(axis.cross(size)); + } + + let (width, height) = axis.pack(main, cross); + let size = limits.resolve(Size::new(width, height)); + + let (padding_x, padding_y) = axis.pack(padding, padding * 2.0); + + Node::with_children( + Size::new(size.width + padding_x, size.height + padding_y), + nodes, + ) +} -- cgit From bfe19193b95e9d1be0694bbc6a96e20a9aefdc09 Mon Sep 17 00:00:00 2001 From: Héctor Ramón Jiménez Date: Mon, 11 Nov 2019 03:20:33 +0100 Subject: Fix integer overflow in `flex::resolve` --- native/src/layout/flex.rs | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'native/src/layout/flex.rs') diff --git a/native/src/layout/flex.rs b/native/src/layout/flex.rs index 98cc344e..ec3e2d00 100644 --- a/native/src/layout/flex.rs +++ b/native/src/layout/flex.rs @@ -63,7 +63,8 @@ where { let limits = limits.pad(padding); - let mut total_non_fill = spacing as f32 * (children.len() - 1) as f32; + let mut total_non_fill = + spacing as f32 * (children.len() as i32 - 1).max(0) as f32; let mut fill_sum = 0; let mut nodes: Vec = Vec::with_capacity(children.len()); -- cgit From ceb02f4a36769c488c2525db2fb73f092a6c2706 Mon Sep 17 00:00:00 2001 From: Héctor Ramón Jiménez Date: Mon, 11 Nov 2019 05:26:08 +0100 Subject: Implement `Container` widget Remove `align_self` and `justify_content` methods --- native/src/layout/flex.rs | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) (limited to 'native/src/layout/flex.rs') diff --git a/native/src/layout/flex.rs b/native/src/layout/flex.rs index ec3e2d00..7a2b0d70 100644 --- a/native/src/layout/flex.rs +++ b/native/src/layout/flex.rs @@ -17,7 +17,7 @@ // limitations under the License. use crate::{ layout::{Limits, Node}, - Element, Size, + Align, Element, Size, }; #[derive(Debug)] @@ -56,6 +56,7 @@ pub fn resolve( limits: &Limits, padding: f32, spacing: f32, + align_items: Align, children: &[Element<'_, Message, Renderer>], ) -> Node where @@ -66,6 +67,7 @@ where let mut total_non_fill = spacing as f32 * (children.len() as i32 - 1).max(0) as f32; let mut fill_sum = 0; + let mut cross = axis.cross(limits.min()); let mut nodes: Vec = Vec::with_capacity(children.len()); nodes.resize(children.len(), Node::default()); @@ -81,8 +83,10 @@ where let child_limits = Limits::new(Size::ZERO, limits.max()); let layout = child.layout(renderer, &child_limits); + let size = layout.size(); - total_non_fill += axis.main(layout.size()); + total_non_fill += axis.main(size); + cross = cross.max(axis.cross(size)); nodes[i] = layout; } else { @@ -120,13 +124,13 @@ where ); let layout = child.layout(renderer, &child_limits); + cross = cross.max(axis.cross(layout.size())); nodes[i] = layout; } } let mut main = padding; - let mut cross = axis.cross(limits.min()); for (i, node) in nodes.iter_mut().enumerate() { if i > 0 { @@ -138,10 +142,18 @@ where node.bounds.x = x; node.bounds.y = y; + match axis { + Axis::Horizontal => { + node.align(Align::Start, align_items, Size::new(0.0, cross)); + } + Axis::Vertical => { + node.align(align_items, Align::Start, Size::new(cross, 0.0)); + } + } + let size = node.size(); main += axis.main(size); - cross = cross.max(axis.cross(size)); } let (width, height) = axis.pack(main, cross); -- cgit