Raph Levien raphlinus

Scene graph

enum Node {
    Group(Group),
    Fill(Fill),
    Stroke(Stroke),
    Clip(Clip),
}

Kenny Kerr posted My Rust adventure begins this morning, and I tweeted "This seems like a pretty big deal - Rust is uniquely able to bridge the gap between performant systems programming and the safe, high level abstractions needed to build applications." This was a strong statement, and sparked a little discussion, so I'd like to clarify a bit.

The main controversy was about whether Rust is truly unique in this regard, or whether other languages can possibly satisfy the requirement of being a solid foundation for operating systems while also avoiding the pitfalls of C and C++. I argue that this role requires a language to be suitable for a very wide range of problem domains. Latency-critical applications such as pro audio are a fairly minor niche, and the vast majority of things people do at computers don't require that kind of low-level control, but if supporting, say, pro audio is one of the requirements

layout

post

title

The smooth resize test

date

2019-06-17 07:26:42 -0700

scatter

This crate contains an implementation of Radial Basis Function multidimensional interpolation. For an excellent introduction to the topic, see the [SIGGRAPH 2014 course notes].

The input is a set of datapoints, each of which has coordinates in some multidimensional space, and a value, also provided as a vector. For example, for the colorfield images below, the coordinates are 2D, and the values are a 3-vector, one each for red, green, and blue. The result is a Scatter struct that can then be evaluated at any coordinate. The idea is that the values vary smoothly with the coordinates, but coincide with the input at each

	# Script to decompose components with mismatched 2x2 matrix
	# See https://github.com/googlefonts/fontmake/issues/595
	for glyph in Glyphs.font.glyphs:
	#print glyph
	xforms = []
	mismatch = []
	for (i, layer) in enumerate(glyph.layers):
	for (j, component) in enumerate(layer.components):
	if i == 0:
	xforms.append(component.transform)

	// Methodology: start with pctl_kernel.hlsl from https://github.com/bzm3r/piet-dx12
	// Expand includes by hand.
	// Use http://shader-playground.timjones.io/
	// Use DXC compiler, cs_6_0 profile, set entry point, SPIRV out
	// Chain spirv-cross, Metal out

	#include <metal_stdlib>
	#include <simd/simd.h>

	using namespace metal;

	//
	// AppDelegate.m
	// Pasteboard toy
	//
	// Created by Raph Levien on 8/10/19.
	// Copyright © 2019 Raph Levien. All rights reserved.
	//

	#import "AppDelegate.h"

	========================
	creating window...
	width: 1424
	height: 704
	tile_side_length_in_pixels: 8
	per_tile_command_lists_num_tiles_per_tg_x: 32
	per_tile_command_lists_num_tiles_per_tg_y: 1
	num_tiles_x: 192
	num_tiles_y: 88
	canvas_quad_width: 1536

	// Sketch of new widget scheme for druid. Some pseudocode within.

	/// Base of a widget.
	///
	/// Name should likely change, this name is chosen to express
	/// what's actually in it.
	pub struct Base<W: WidgetInner> {
	state: BaseState,

	inner: W,

	pub trait Lens<T, U> {
	fn get<'a>(&self, data: &'a T) -> &'a U;

	fn with_mut<F: FnOnce(&mut U)>(&self, data: &mut T, f: F);
	}