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Dusk (#715)

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Co-authored-by: Stephen Gutekanst <stephen@hexops.com>
This commit is contained in:
Ali Chraghi 2023-03-05 22:44:54 +03:30 • committed by GitHub
parent 2b6f3fb1d9
commit 94fbc5d27f
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4
build.zig
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@ -9,6 +9,7 @@ const sysjs = @import("libs/sysjs/build.zig");
const earcut = @import("libs/earcut/build.zig");
const gamemode = @import("libs/gamemode/build.zig");
const model3d = @import("libs/model3d/build.zig");
const dusk = @import("libs/dusk/build.zig");
const wasmserve = @import("tools/wasmserve/wasmserve.zig");
const gpu_dawn = @import("libs/gpu-dawn/sdk.zig").Sdk(.{
.glfw_include_dir = sdkPath("/libs/glfw/upstream/glfw/include"),
@ -66,6 +67,7 @@ pub fn build(b: *std.Build) !void {
const basisu_test_step = b.step("test-basisu", "Run Basis-Universal library tests");
const sysaudio_test_step = b.step("test-sysaudio", "Run sysaudio library tests");
const model3d_test_step = b.step("test-model3d", "Run Model3D library tests");
const dusk_test_step = b.step("test-dusk", "Run Dusk library tests");
const mach_test_step = b.step("test-mach", "Run Engine library tests");
core_test_step.dependOn(&(try core.testStep(b, optimize, target)).step);
@ -74,6 +76,7 @@ pub fn build(b: *std.Build) !void {
basisu_test_step.dependOn(&basisu.testStep(b, optimize, target).step);
sysaudio_test_step.dependOn(&sysaudio.testStep(b, optimize, target).step);
model3d_test_step.dependOn(&model3d.testStep(b, optimize, target).step);
dusk_test_step.dependOn(&dusk.testStep(b, optimize, target).step);
mach_test_step.dependOn(&testStep(b, optimize, target).step);
all_tests_step.dependOn(core_test_step);
@ -82,6 +85,7 @@ pub fn build(b: *std.Build) !void {
all_tests_step.dependOn(freetype_test_step);
all_tests_step.dependOn(sysaudio_test_step);
all_tests_step.dependOn(model3d_test_step);
all_tests_step.dependOn(dusk_test_step);
all_tests_step.dependOn(mach_test_step);
const shaderexp_app = try App.init(

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@ -0,0 +1,2 @@
* text=auto eol=lf
upstream/** linguist-vendored

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github: slimsag

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Please send your change to [the main repository](https://github.com/hexops/mach/tree/main/libs/dusk) instead, sorry for the trouble!
This helps us avoid some complex merge conflicts we run into when changes are made to both repositories and history needs to be reconciled. Keeping PRs in just that repository enables us to use `git subtree` to trivially keep the two repositories in sync.
Once your PR is merged over there, it'll automatically sync to this repository.

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@ -0,0 +1,16 @@
name: CI
on:
- push
- pull_request
jobs:
x86_64-linux:
runs-on: ubuntu-latest
steps:
- name: Checkout
uses: actions/checkout@v2
- name: Setup Zig
run: |
sudo apt install xz-utils
sudo sh -c 'wget -c https://ziglang.org/builds/zig-linux-x86_64-0.11.0-dev.1605+abc9530a8.tar.xz -O - | tar -xJ --strip-components=1 -C /usr/local/bin'
- name: test
run: zig build test

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@ -0,0 +1,18 @@
# This file is for zig-specific build artifacts.
# If you have OS-specific or editor-specific files to ignore,
# such as *.swp or .DS_Store, put those in your global
# ~/.gitignore and put this in your ~/.gitconfig:
#
# [core]
# excludesfile = ~/.gitignore
#
# Cheers!
# -andrewrk
zig-cache/
zig-out/
/release/
/debug/
/build/
/build-*/
/docgen_tmp/

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libs/dusk/LICENSE Normal file
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@ -0,0 +1,13 @@
Copyright 2023, Hexops Contributors (given via the Git commit history).
All documentation, image, sound, font, and 2D/3D model files are CC-BY-4.0 licensed unless
otherwise noted. You may get a copy of this license at https://creativecommons.org/licenses/by/4.0
Files in a directory with a separate LICENSE file may contain files under different license terms,
described within that LICENSE file.
All other files are licensed under the Apache License, Version 2.0 (see LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
or the MIT license (see LICENSE-MIT or http://opensource.org/licenses/MIT), at your option.
All files in the project without exclusions may not be copied, modified, or distributed except
according to the terms above.

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@ -0,0 +1,202 @@
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@ -0,0 +1,25 @@
Copyright (c) 2021 Hexops Contributors (given via the Git commit history).
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SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.

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@ -0,0 +1,29 @@
# mach/dusk - WebGPU implementation in Zig
This repository is a separate copy of the same library in the [main Mach repository](https://github.com/hexops/mach), and is automatically kept in sync, so that anyone can use this library in their own project if they like!
## Current Status
Dusk is in **very early stages** and under heavy development; there are hundreds of known bugs/missing features.
### WGSL compiler
- [x] Parser
- [ ] Ast analysis (WIP!)
- [ ] Transpilation targets
- [ ] GLSL
- [ ] Spir-V
- [ ] HLSL
- [ ] Metal
## Join the community
Join the Mach community [on Discord](https://discord.gg/XNG3NZgCqp) to discuss this project, ask questions, get help, etc.
## Issues
Issues are tracked in the [main Mach repository](https://github.com/hexops/mach/issues?q=is%3Aissue+is%3Aopen+label%3Adusk).
## Contributing
Contributions are very welcome. Pull requests must be sent to [the main repository](https://github.com/hexops/mach/tree/main/libs/dusk) to avoid some complex merge conflicts we'd get by accepting contributions in both repositories. Once the changes are merged there, they'll get sync'd to this repository automatically.

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const std = @import("std");
pub fn build(b: *std.Build) !void {
const optimize = b.standardOptimizeOption(.{});
const target = b.standardTargetOptions(.{});
const test_step = b.step("test", "Run library tests");
test_step.dependOn(&testStep(b, optimize, target).step);
}
pub fn module(b: *std.build.Builder) *std.build.Module {
return b.createModule(.{ .source_file = .{ .path = sdkPath("/src/main.zig") } });
}
pub fn testStep(b: *std.Build, optimize: std.builtin.OptimizeMode, target: std.zig.CrossTarget) *std.build.RunStep {
const main_tests = b.addTest(.{
.name = "dusk-tests",
.kind = .test_exe,
.root_source_file = .{ .path = sdkPath("/test/main.zig") },
.target = target,
.optimize = optimize,
});
main_tests.addModule("dusk", module(b));
main_tests.install();
return main_tests.run();
}
fn sdkPath(comptime suffix: []const u8) []const u8 {
if (suffix[0] != '/') @compileError("suffix must be an absolute path");
return comptime blk: {
const root_dir = std.fs.path.dirname(@src().file) orelse ".";
break :blk root_dir ++ suffix;
};
}

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const std = @import("std");
const Ast = @import("Ast.zig");
const Token = @import("Token.zig");
const ErrorMsg = @import("main.zig").ErrorMsg;
const Analyse = @This();
allocator: std.mem.Allocator,
tree: *const Ast,
errors: std.ArrayListUnmanaged(ErrorMsg),
pub fn deinit(self: *Analyse) void {
for (self.errors.items) |*err_msg| err_msg.deinit(self.allocator);
self.errors.deinit(self.allocator);
}
pub fn analyseRoot(self: *Analyse) !void {
const global_items = self.tree.spanToList(0);
for (global_items, 0..) |node_i, i| {
try self.checkRedeclaration(global_items[i + 1 ..], node_i);
try self.globalDecl(global_items, node_i);
}
if (self.errors.items.len > 0) {
return error.Analysing;
}
}
pub fn globalDecl(self: *Analyse, parent_scope: []const Ast.Index, node_i: Ast.Index) !void {
switch (self.tree.nodeTag(node_i)) {
.global_variable => {}, // TODO
.struct_decl => try self.structDecl(parent_scope, node_i),
else => std.debug.print("Global Decl TODO: {}\n", .{self.tree.nodeTag(node_i)}),
}
}
pub fn structDecl(self: *Analyse, parent_scope: []const Ast.Index, node: Ast.Index) !void {
const member_list = self.tree.spanToList(self.tree.nodeLHS(node));
for (member_list, 0..) |member_node, i| {
try self.checkRedeclaration(member_list[i + 1 ..], member_node);
const member_loc = self.tree.tokenLoc(self.tree.nodeToken(member_node));
const member_name = member_loc.slice(self.tree.source);
const member_type_node = self.tree.nodeRHS(member_node);
switch (self.tree.nodeTag(member_type_node)) {
.scalar_type,
.vector_type,
.matrix_type,
.atomic_type,
=> {},
.array_type => {
if (self.tree.nodeRHS(member_type_node) == Ast.null_index and
i != member_list.len - 1)
{
try self.addError(
member_loc,
"struct member with runtime-sized array type, must be the last member of the structure",
.{},
null,
);
}
},
.user_type => {
_ = self.findDeclNode(parent_scope, member_name) orelse {
try self.addError(
member_loc, // TODO
"use of undeclared identifier '{s}'",
.{member_name},
null,
);
continue;
};
},
else => {
try self.addError(
member_loc,
"invalid struct member type '{s}'",
.{member_name},
null,
);
},
}
}
}
pub fn findDeclNode(self: *Analyse, scope_items: []const Ast.Index, name: []const u8) ?Ast.Index {
for (scope_items) |node| {
const node_token = self.declNameToken(node) orelse continue;
if (std.mem.eql(u8, name, self.tree.tokenLoc(node_token).slice(self.tree.source))) {
return node;
}
}
return null;
}
pub fn checkRedeclaration(self: *Analyse, scope_items: []const Ast.Index, decl_node: Ast.Index) !void {
const decl_token_loc = self.tree.tokenLoc(self.declNameToken(decl_node).?);
const decl_name = decl_token_loc.slice(self.tree.source);
for (scope_items) |redecl_node| {
std.debug.assert(decl_node != redecl_node);
const redecl_token_loc = self.tree.tokenLoc(self.declNameToken(redecl_node).?);
const redecl_name = redecl_token_loc.slice(self.tree.source);
if (std.mem.eql(u8, decl_name, redecl_name)) {
try self.addError(
redecl_token_loc,
"redeclaration of '{s}'",
.{decl_name},
try ErrorMsg.Note.create(
self.allocator,
decl_token_loc,
"other declaration here",
.{},
),
);
}
}
}
pub fn declNameToken(self: *Analyse, node: Ast.Index) ?Ast.Index {
return switch (self.tree.nodeTag(node)) {
.global_variable => self.tree.extraData(Ast.Node.GlobalVarDecl, self.tree.nodeLHS(node)).name,
.struct_decl,
.fn_decl,
.global_constant,
.override,
.type_alias,
=> self.tree.nodeToken(node) + 1,
.struct_member => self.tree.nodeToken(node),
else => null,
};
}
pub fn addError(
self: *Analyse,
loc: Token.Loc,
comptime format: []const u8,
args: anytype,
note: ?ErrorMsg.Note,
) !void {
const err_msg = try ErrorMsg.create(self.allocator, loc, format, args, note);
try self.errors.append(self.allocator, err_msg);
}

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const std = @import("std");
const Analyse = @import("Analyse.zig");
const Parser = @import("Parser.zig");
const Token = @import("Token.zig");
const Tokenizer = @import("Tokenizer.zig");
const ErrorMsg = @import("main.zig").ErrorMsg;
const Extension = @import("main.zig").Extension;
const Ast = @This();
pub const NodeList = std.MultiArrayList(Node);
pub const TokenList = std.MultiArrayList(Token);
source: [:0]const u8,
tokens: TokenList.Slice,
nodes: NodeList.Slice,
extra: []const Index,
pub fn deinit(tree: *Ast, allocator: std.mem.Allocator) void {
tree.tokens.deinit(allocator);
tree.nodes.deinit(allocator);
allocator.free(tree.extra);
tree.* = undefined;
}
pub const ParseResult = union(enum) {
errors: []ErrorMsg,
tree: Ast,
};
/// parses a TranslationUnit (WGSL Program)
pub fn parse(allocator: std.mem.Allocator, source: [:0]const u8) !ParseResult {
const estimated_tokens = source.len / 8;
var tokens = std.MultiArrayList(Token){};
try tokens.ensureTotalCapacity(allocator, estimated_tokens);
var tokenizer = Tokenizer.init(source);
while (true) {
const tok = tokenizer.next();
try tokens.append(allocator, tok);
if (tok.tag == .eof) break;
}
var p = Parser{
.allocator = allocator,
.source = source,
.tok_i = 0,
.tokens = tokens.toOwnedSlice(),
.nodes = .{},
.extra = .{},
.scratch = .{},
.errors = .{},
.extensions = Extension.Array.initFill(false),
};
defer p.deinit();
errdefer p.tokens.deinit(allocator);
// TODO: make sure tokens:nodes ratio is right
const estimated_node_count = (tokens.len + 2) / 2;
try p.nodes.ensureTotalCapacity(allocator, estimated_node_count);
p.parseRoot() catch |err| {
if (err == error.Parsing) {
p.tokens.deinit(allocator);
return .{ .errors = try p.errors.toOwnedSlice(allocator) };
}
return err;
};
return .{
.tree = .{
.source = source,
.tokens = p.tokens,
.nodes = p.nodes.toOwnedSlice(),
.extra = try p.extra.toOwnedSlice(allocator),
},
};
}
pub fn analyse(tree: Ast, allocator: std.mem.Allocator) !?[]ErrorMsg {
var analyser = Analyse{
.allocator = allocator,
.tree = &tree,
.errors = .{},
};
defer analyser.deinit();
analyser.analyseRoot() catch |err| {
if (err == error.Analysing) {
return try analyser.errors.toOwnedSlice(allocator);
}
return err;
};
return null;
}
pub fn spanToList(tree: Ast, span: Ast.Index) []const Ast.Index {
std.debug.assert(tree.nodeTag(span) == .span);
return tree.extra[tree.nodeLHS(span)..tree.nodeRHS(span)];
}
pub fn extraData(tree: Ast, comptime T: type, index: Ast.Index) T {
const fields = std.meta.fields(T);
var result: T = undefined;
inline for (fields, 0..) |field, i| {
comptime std.debug.assert(field.type == Ast.Index);
@field(result, field.name) = tree.extra[index + i];
}
return result;
}
pub fn tokenTag(tree: Ast, i: Index) Token.Tag {
return tree.tokens.items(.tag)[i];
}
pub fn tokenLoc(tree: Ast, i: Index) Token.Loc {
return tree.tokens.items(.loc)[i];
}
pub fn nodeTag(tree: Ast, i: Index) Node.Tag {
return tree.nodes.items(.tag)[i];
}
pub fn nodeToken(tree: Ast, i: Index) Index {
return tree.nodes.items(.main_token)[i];
}
pub fn nodeLHS(tree: Ast, i: Index) Index {
return tree.nodes.items(.lhs)[i];
}
pub fn nodeRHS(tree: Ast, i: Index) Index {
return tree.nodes.items(.rhs)[i];
}
pub const Index = u32;
pub const null_index: Index = 0;
pub const Node = struct {
tag: Tag,
main_token: Index,
lhs: Index = null_index,
rhs: Index = null_index,
pub const Tag = enum {
/// an slice to extra field [LHS..RHS]
/// TOK : undefined
/// LHS : Index
/// RHS : Index
span,
// ####### GlobalDecl #######
/// TOK : k_var
/// LHS : GlobalVarDecl
/// RHS : Expr?
global_variable,
/// TOK : k_const
/// LHS : Type
/// RHS : Expr
global_constant,
/// TOK : k_override
/// LHS : OverrideDecl
/// RHS : Expr
override,
/// TOK : k_type
/// LHS : Type
/// RHS : --
type_alias,
/// TOK : k_const_assert
/// LHS : Expr
/// RHS : --
const_assert,
/// TOK : k_struct
/// LHS : span(struct_member)
/// RHS : --
struct_decl,
/// TOK : ident
/// LHS : span(Attribute)
/// RHS : Type
struct_member,
/// TOK : k_fn
/// LHS : FnProto
/// RHS : block
fn_decl,
/// TOK : ident
/// LHS : ? Attributes
/// RHS : type
fn_param,
// ####### Statement #######
// block = span(Statement)
/// TOK : k_return
/// LHS : Expr?
/// RHS : --
@"return",
/// TOK : k_discard
/// LHS : --
/// RHS : --
discard,
/// TOK : k_loop
/// LHS : block
/// RHS : --
loop,
/// TOK : k_continuing
/// LHS : block
/// RHS : --
continuing,
/// TOK : k_break
/// LHS : Expr
/// RHS : --
break_if,
/// TOK : k_break
/// LHS : --
/// RHS : --
@"break",
/// TOK : k_continue
/// LHS : --
/// RHS : --
@"continue",
/// TOK : k_if
/// LHS : Expr
/// RHS : blcok
@"if",
/// RHS is else body
/// TOK : k_if
/// LHS : if
/// RHS : blcok
if_else,
/// TOK : k_if
/// LHS : if
/// RHS : if, if_else, if_else_if
if_else_if,
/// TOK : k_switch
/// LHS : Expr
/// RHS : span(switch_case, switch_default, switch_case_default)
@"switch",
/// TOK : k_case
/// LHS : span(Expr)
/// RHS : block
switch_case,
/// TOK : k_default
/// LHS : block
/// RHS : --
switch_default,
/// switch_case with default (`case 1, 2, default {}`)
/// TOK : k_case
/// LHS : span(Expr)
/// RHS : block
switch_case_default,
/// TOK : k_var
/// LHS : VarDecl
/// RHS : Expr?
var_decl,
/// TOK : k_const
/// LHS : Type?
/// RHS : Expr
const_decl,
/// TOK : k_let
/// LHS : Type?
/// RHS : Expr
let_decl,
/// TOK : k_while
/// LHS : Expr
/// RHS : block
@"while",
/// TOK : k_for
/// LHS : ForHeader
/// RHS : block
@"for",
/// TOK : plus_plus, minus_minus
/// LHS : Expr
increase_decrement,
/// TOK : plus_equal, minus_equal,
/// times_equal, division_equal,
/// modulo_equal, and_equal,
/// or_equal, xor_equal,
/// shift_right_equal, shift_left_equal
/// LHS : Expr
/// RHS : Expr
compound_assign,
/// TOK : equal
/// LHS : Expr
/// RHS : --
phony_assign,
// ####### Type #######
/// TOK : k_i32, k_u32, k_f32, k_f16, k_bool
/// LHS : --
/// RHS : --
scalar_type,
/// TOK : k_sampler, k_comparison_sampler
/// LHS : --
/// RHS : --
sampler_type,
/// TOK : k_vec2, k_vec3, k_vec4
/// LHS : Type
/// RHS : --
vector_type,
/// TOK : k_mat2x2, k_mat2x3, k_mat2x4,
/// k_mat3x2, k_mat3x3, k_mat3x4,
/// k_mat4x2, k_mat4x3, k_mat4x4
/// LHS : Type
/// RHS : --
matrix_type,
/// TOK : k_atomic
/// LHS : Type
/// RHS : --
atomic_type,
/// TOK : k_array
/// LHS : Type
/// RHS : Expr?
array_type,
/// TOK : k_ptr
/// LHS : Type
/// RHS : PtrType
ptr_type,
/// TOK : k_texture_1d, k_texture_2d, k_texture_2d_array,
/// k_texture_3d, k_texture_cube, k_texture_cube_array
/// LHS : Type
/// RHS : --
sampled_texture_type,
/// TOK : k_texture_multisampled_2d
/// LHS : Type
/// RHS : --
multisampled_texture_type,
/// TOK : k_texture_external
/// LHS : Type
/// RHS : --
external_texture_type,
/// TOK : k_texture_storage_1d, k_texture_storage_2d,
/// k_texture_storage_2d_array, k_texture_storage_3d
/// LHS : Index(Token(TexelFormat))
/// RHS : Index(Token(AccessMode))
storage_texture_type,
/// TOK : k_texture_depth_2d, k_texture_depth_2d_array
/// k_texture_depth_cube, k_texture_depth_cube_array
/// k_texture_depth_multisampled_2d
/// LHS : --
/// RHS : --
depth_texture_type,
/// TOK : ident
/// LHS : --
/// RHS : --
user_type,
// ####### Attr #######
// TOK : attr
attr,
/// TOK : attr
/// LHS : Expr
/// RHS : --
attr_one_arg,
/// TOK : attr
/// LHS : Index(Token(BuiltinValue))
/// RHS : --
attr_builtin,
/// TOK : attr
/// LHS : WorkgroupSize
/// RHS : --
attr_workgroup_size,
/// TOK : attr
/// LHS : Index(Token(InterpolationType))
/// RHS : Index(Token(InterpolationSample))
attr_interpolate,
// ####### Expr #######
// see both Parser.zig and https://gpuweb.github.io/gpuweb/wgsl/#expression-grammar
/// TOK : *
/// LHS : Expr
/// RHS : Expr
mul,
/// TOK : /
/// LHS : Expr
/// RHS : Expr
div,
/// TOK : %
/// LHS : Expr
/// RHS : Expr
mod,
/// TOK : +
/// LHS : Expr
/// RHS : Expr
add,
/// TOK : -
/// LHS : Expr
/// RHS : Expr
sub,
/// TOK : <<
/// LHS : Expr
/// RHS : Expr
shift_left,
/// TOK : >>
/// LHS : Expr
/// RHS : Expr
shift_right,
/// TOK : &
/// LHS : Expr
/// RHS : Expr
binary_and,
/// TOK : |
/// LHS : Expr
/// RHS : Expr
binary_or,
/// TOK : ^
/// LHS : Expr
/// RHS : Expr
binary_xor,
/// TOK : &&
/// LHS : Expr
/// RHS : Expr
circuit_and,
/// TOK : ||
/// LHS : Expr
/// RHS : Expr
circuit_or,
/// TOK : !
/// LHS : Expr
/// RHS : --
not,
/// TOK : -
/// LHS : Expr
/// RHS : --
negate,
/// TOK : *
/// LHS : Expr
/// RHS : --
deref,
/// TOK : &
/// LHS : Expr
/// RHS : --
addr_of,
/// TOK : ==
/// LHS : Expr
/// RHS : Expr
equal,
/// TOK : !=
/// LHS : Expr
/// RHS : Expr
not_equal,
/// TOK : <
/// LHS : Expr
/// RHS : Expr
less,
/// TOK : <=
/// LHS : Expr
/// RHS : Expr
less_equal,
/// TOK : >
/// LHS : Expr
/// RHS : Expr
greater,
/// TOK : >=
/// LHS : Expr
/// RHS : Expr
greater_equal,
/// for identifier, array without element type specified,
/// vector prefix (e.g. vec2) and matrix prefix (e.g. mat2x2) LHS is null
/// see callExpr in Parser.zig if you don't understand this
///
/// TOK : ident, k_array, 'scalar keywords', 'vector keywords', 'matrix keywords'
/// LHS : (scalar_type, vector_type, matrix_type, array_type)?
/// RHS : arguments (Expr span)
call,
/// TOK : k_bitcast
/// LHS : Type
/// RHS : Expr
bitcast,
/// TOK : ident
/// LHS : --
/// RHS : --
ident_expr,
/// LHS is prefix expression
/// TOK : ident
/// LHS : Expr
component_access,
/// LHS is prefix expression
/// TOK : bracket_left
/// LHS : Expr
/// RHS : Expr
index_access,
// ####### Literals #######
/// TOK : k_true, k_false
/// LHS : --
/// RHS : --
bool_literal,
/// TOK : number
/// LHS : --
/// RHS : --
number_literal,
};
pub const GlobalVarDecl = struct {
/// span(Attr)?
attrs: Index = null_index,
/// Token(ident)
name: Index,
/// Token(AddrSpace)?
addr_space: Index = null_index,
/// Token(AccessMode)?
access_mode: Index = null_index,
/// Type?
type: Index = null_index,
};
pub const VarDecl = struct {
/// Token(ident)
name: Index,
/// Token(AddrSpace)?
addr_space: Index = null_index,
/// Token(AccessMode)?
access_mode: Index = null_index,
/// Type?
type: Index = null_index,
};
pub const OverrideDecl = struct {
/// span(Attr)?
attrs: Index = null_index,
/// Type?
type: Index = null_index,
};
pub const PtrType = struct {
/// Token(AddrSpace)
addr_space: Index,
/// Token(AccessMode)?
access_mode: Index = null_index,
};
pub const WorkgroupSize = struct {
/// Expr
x: Index,
/// Expr?
y: Index = null_index,
/// Expr?
z: Index = null_index,
};
pub const FnProto = struct {
/// span(Attr)?
attrs: Index = null_index,
/// span(fn_param)?
params: Index = null_index,
/// span(Attr)?
result_attrs: Index = null_index,
/// Type?
result_type: Index = null_index,
};
pub const IfStatement = struct {
/// Expr
cond: Index,
/// block
body: Index,
};
pub const ForHeader = struct {
/// var_decl, const_decl, let_decl, phony_assign, compound_assign
init: Index = null_index,
/// Expr
cond: Index = null_index,
/// call, phony_assign, compound_assign
update: Index = null_index,
};
};
pub const BuiltinValue = enum {
vertex_index,
instance_index,
position,
front_facing,
frag_depth,
local_invocation_id,
local_invocation_index,
global_invocation_id,
workgroup_id,
num_workgroups,
sample_index,
sample_mask,
};
pub const InterpolationType = enum {
perspective,
linear,
flat,
};
pub const InterpolationSample = enum {
center,
centroid,
sample,
};
pub const AddressSpace = enum {
function,
private,
workgroup,
uniform,
storage,
};
pub const AccessMode = enum {
read,
write,
read_write,
};
pub const Attribute = enum {
invariant,
@"const",
vertex,
fragment,
compute,
@"align",
binding,
group,
id,
location,
size,
builtin,
workgroup_size,
interpolate,
};
pub const TexelFormat = enum {
rgba8unorm,
rgba8snorm,
rgba8uint,
rgba8sint,
rgba16uint,
rgba16sint,
rgba16float,
r32uint,
r32sint,
r32float,
rg32uint,
rg32sint,
rg32float,
rgba32uint,
rgba32sint,
rgba32float,
bgra8unorm,
};

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const std = @import("std");
tag: Tag,
loc: Loc,
pub const Loc = struct {
start: u32,
end: u32,
pub const Extra = struct {
line: u32,
col: u32,
line_start: u32,
line_end: u32,
};
pub fn slice(self: Loc, source: []const u8) []const u8 {
return source[self.start..self.end];
}
pub fn extraInfo(self: Loc, source: []const u8) Extra {
var result = Extra{
.line = 1,
.col = 1,
.line_start = 0,
.line_end = @intCast(u32, source.len),
};
for (source[0..self.start], 0..) |c, i| {
if (c == '\n') {
result.line += 1;
result.line_start = @intCast(u32, i) + 1;
}
}
for (source[self.end..], 0..) |c, i| {
if (c == '\n') {
result.line_end = self.end + @intCast(u32, i);
break;
}
}
result.col += self.start - result.line_start;
return result;
}
};
pub const Tag = enum {
eof,
invalid,
ident,
/// any number literal
number,
/// '&'
@"and",
/// '&&'
and_and,
/// '->'
arrow,
/// '@'
attr,
/// '/'
division,
/// '!'
bang,
/// '{'
brace_left,
/// '}'
brace_right,
/// '['
bracket_left,
/// ']'
bracket_right,
/// ':'
colon,
/// ','
comma,
/// '='
equal,
/// '=='
equal_equal,
/// '>'
greater_than,
/// '>='
greater_than_equal,
/// '>>'
shift_right,
/// '<'
less_than,
/// '<='
less_than_equal,
/// '<<'
shift_left,
/// '%'
mod,
/// '-'
minus,
/// '--'
minus_minus,
/// '!='
not_equal,
/// '.'
period,
/// '+'
plus,
/// '++'
plus_plus,
/// '|'
@"or",
/// '||'
or_or,
/// '('
paren_left,
/// ')'
paren_right,
/// ';'
semicolon,
/// '*'
star,
/// '~'
tilde,
/// '_'
underscore,
/// '^'
xor,
/// '+='
plus_equal,
/// '-='
minus_equal,
/// '*='
times_equal,
/// '/='
division_equal,
/// '%='
modulo_equal,
/// '&='
and_equal,
/// '|='
or_equal,
/// '^='
xor_equal,
/// '>>='
shift_right_equal,
/// '<<='
shift_left_equal,
/// 'array'
k_array,
/// 'atomic'
k_atomic,
/// 'bitcast'
k_bitcast,
/// 'bool'
k_bool,
/// 'break'
k_break,
/// 'case'
k_case,
/// 'const'
k_const,
/// 'continue'
k_continue,
/// 'continuing'
k_continuing,
/// 'discard'
k_discard,
/// 'default'
k_default,
/// 'else'
k_else,
/// 'enable'
k_enable,
/// 'f16'
k_f16,
/// 'f32'
k_f32,
/// 'fallthrough'
k_fallthrough,
/// 'false'
k_false,
/// 'fn'
k_fn,
/// 'for'
k_for,
/// 'i32'
k_i32,
/// 'if'
k_if,
/// 'let'
k_let,
/// 'loop'
k_loop,
/// 'mat2x2'
k_mat2x2,
/// 'mat2x3'
k_mat2x3,
/// 'mat2x4'
k_mat2x4,
/// 'mat3x2'
k_mat3x2,
/// 'mat3x3'
k_mat3x3,
/// 'mat3x4'
k_mat3x4,
/// 'mat4x2'
k_mat4x2,
/// 'mat4x3'
k_mat4x3,
/// 'mat4x4'
k_mat4x4,
/// 'override'
k_override,
/// 'ptr'
k_ptr,
/// 'return'
k_return,
/// 'sampler'
k_sampler,
/// 'sampler_comparison'
k_comparison_sampler,
/// 'const_assert'
k_const_assert,
/// 'struct'
k_struct,
/// 'switch'
k_switch,
/// 'texture_depth_2d'
k_texture_depth_2d,
/// 'texture_depth_2d_array'
k_texture_depth_2d_array,
/// 'texture_depth_cube'
k_texture_depth_cube,
/// 'texture_depth_cube_array'
k_texture_depth_cube_array,
/// 'texture_depth_multisampled_2d'
k_texture_depth_multisampled_2d,
/// 'texture_external'
k_texture_external,
/// 'texture_multisampled_2d'
k_texture_multisampled_2d,
/// 'texture_1d'
k_texture_sampled_1d,
/// 'texture_2d'
k_texture_sampled_2d,
/// 'texture_2d_array'
k_texture_sampled_2d_array,
/// 'texture_3d'
k_texture_sampled_3d,
/// 'texture_cube'
k_texture_sampled_cube,
/// 'texture_cube_array'
k_texture_sampled_cube_array,
/// 'texture_storage_1d'
k_texture_storage_1d,
/// 'texture_storage_2d'
k_texture_storage_2d,
/// 'texture_storage_2d_array'
k_texture_storage_2d_array,
/// 'texture_storage_3d'
k_texture_storage_3d,
/// 'true'
k_true,
/// 'type'
k_type,
/// 'u32'
k_u32,
/// 'var'
k_var,
/// 'vec2'
k_vec2,
/// 'vec3'
k_vec3,
/// 'vec4'
k_vec4,
/// 'while'
k_while,
pub fn symbol(self: Tag) []const u8 {
return switch (self) {
.eof => "EOF",
.invalid => "invalid bytes",
.ident => "an identifier",
.number => "a number literal",
.@"and" => "&",
.and_and => "&&",
.arrow => "->",
.attr => "@",
.division => "/",
.bang => "!",
.brace_left => "{",
.brace_right => "}",
.bracket_left => "[",
.bracket_right => "]",
.colon => ":",
.comma => ",",
.equal => "=",
.equal_equal => "==",
.greater_than => ">",
.greater_than_equal => ">=",
.shift_right => ">>",
.less_than => "<",
.less_than_equal => "<=",
.shift_left => "<<",
.mod => "%",
.minus => "-",
.minus_minus => "--",
.not_equal => "!=",
.period => ".",
.plus => "+",
.plus_plus => "++",
.@"or" => "|",
.or_or => "||",
.paren_left => "(",
.paren_right => ")",
.semicolon => ";",
.star => "*",
.tilde => "~",
.underscore => "_",
.xor => "^",
.plus_equal => "+=",
.minus_equal => "-=",
.times_equal => "*=",
.division_equal => "/=",
.modulo_equal => "%=",
.and_equal => "&=",
.or_equal => "|=",
.xor_equal => "^=",
.shift_right_equal => ">>=",
.shift_left_equal => "<<=",
.k_array => "array",
.k_atomic => "atomic",
.k_bitcast => "bitcast",
.k_bool => "bool",
.k_break => "break",
.k_case => "case",
.k_const => "const",
.k_continue => "continue",
.k_continuing => "continuing",
.k_discard => "discard",
.k_default => "default",
.k_else => "else",
.k_enable => "enable",
.k_f16 => "f16",
.k_f32 => "f32",
.k_fallthrough => "fallthrough",
.k_false => "false",
.k_fn => "fn",
.k_for => "for",
.k_i32 => "i32",
.k_if => "if",
.k_let => "let",
.k_loop => "loop",
.k_mat2x2 => "mat2x2",
.k_mat2x3 => "mat2x3",
.k_mat2x4 => "mat2x4",
.k_mat3x2 => "mat3x2",
.k_mat3x3 => "mat3x3",
.k_mat3x4 => "mat3x4",
.k_mat4x2 => "mat4x2",
.k_mat4x3 => "mat4x3",
.k_mat4x4 => "mat4x4",
.k_override => "override",
.k_ptr => "ptr",
.k_return => "return",
.k_sampler => "sampler",
.k_comparison_sampler => "sampler_comparison",
.k_const_assert => "const_assert",
.k_struct => "struct",
.k_switch => "switch",
.k_texture_depth_2d => "texture_depth_2d",
.k_texture_depth_2d_array => "texture_depth_2d_array",
.k_texture_depth_cube => "texture_depth_cube",
.k_texture_depth_cube_array => "texture_depth_cube_array",
.k_texture_depth_multisampled_2d => "texture_depth_multisampled_2d",
.k_texture_external => "texture_external",
.k_texture_multisampled_2d => "texture_multisampled_2d",
.k_texture_sampled_1d => "texture_1d",
.k_texture_sampled_2d => "texture_2d",
.k_texture_sampled_2d_array => "texture_2d_array",
.k_texture_sampled_3d => "texture_3d",
.k_texture_sampled_cube => "texture_cube",
.k_texture_sampled_cube_array => "texture_cube_array",
.k_texture_storage_1d => "texture_storage_1d",
.k_texture_storage_2d => "texture_storage_2d",
.k_texture_storage_2d_array => "texture_storage_2d_array",
.k_texture_storage_3d => "texture_storage_3d",
.k_true => "true",
.k_type => "type",
.k_u32 => "u32",
.k_var => "var",
.k_vec2 => "vec2",
.k_vec3 => "vec3",
.k_vec4 => "vec4",
.k_while => "while",
};
}
};
pub const keywords = std.ComptimeStringMap(Tag, .{
.{ "array", .k_array },
.{ "atomic", .k_atomic },
.{ "bitcast", .k_bitcast },
.{ "bool", .k_bool },
.{ "break", .k_break },
.{ "case", .k_case },
.{ "const", .k_const },
.{ "continue", .k_continue },
.{ "continuing", .k_continuing },
.{ "discard", .k_discard },
.{ "default", .k_default },
.{ "else", .k_else },
.{ "enable", .k_enable },
.{ "f16", .k_f16 },
.{ "f32", .k_f32 },
.{ "fallthrough", .k_fallthrough },
.{ "false", .k_false },
.{ "fn", .k_fn },
.{ "for", .k_for },
.{ "i32", .k_i32 },
.{ "if", .k_if },
.{ "let", .k_let },
.{ "loop", .k_loop },
.{ "mat2x2", .k_mat2x2 },
.{ "mat2x3", .k_mat2x3 },
.{ "mat2x4", .k_mat2x4 },
.{ "mat3x2", .k_mat3x2 },
.{ "mat3x3", .k_mat3x3 },
.{ "mat3x4", .k_mat3x4 },
.{ "mat4x2", .k_mat4x2 },
.{ "mat4x3", .k_mat4x3 },
.{ "mat4x4", .k_mat4x4 },
.{ "override", .k_override },
.{ "ptr", .k_ptr },
.{ "return", .k_return },
.{ "sampler", .k_sampler },
.{ "sampler_comparison", .k_comparison_sampler },
.{ "const_assert", .k_const_assert },
.{ "struct", .k_struct },
.{ "switch", .k_switch },
.{ "texture_depth_2d", .k_texture_depth_2d },
.{ "texture_depth_2d_array", .k_texture_depth_2d_array },
.{ "texture_depth_cube", .k_texture_depth_cube },
.{ "texture_depth_cube_array", .k_texture_depth_cube_array },
.{ "texture_depth_multisampled_2d", .k_texture_depth_multisampled_2d },
.{ "texture_external", .k_texture_external },
.{ "texture_multisampled_2d", .k_texture_multisampled_2d },
.{ "texture_1d", .k_texture_sampled_1d },
.{ "texture_2d", .k_texture_sampled_2d },
.{ "texture_2d_array", .k_texture_sampled_2d_array },
.{ "texture_3d", .k_texture_sampled_3d },
.{ "texture_cube", .k_texture_sampled_cube },
.{ "texture_cube_array", .k_texture_sampled_cube_array },
.{ "texture_storage_1d", .k_texture_storage_1d },
.{ "texture_storage_2d", .k_texture_storage_2d },
.{ "texture_storage_2d_array", .k_texture_storage_2d_array },
.{ "texture_storage_3d", .k_texture_storage_3d },
.{ "true", .k_true },
.{ "type", .k_type },
.{ "u32", .k_u32 },
.{ "var", .k_var },
.{ "vec2", .k_vec2 },
.{ "vec3", .k_vec3 },
.{ "vec4", .k_vec4 },
.{ "while", .k_while },
});

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const std = @import("std");
const Token = @import("Token.zig");
const Tokenizer = @This();
source: [:0]const u8,
index: u32,
const State = enum {
start,
invalid,
ident,
underscore,
number,
block_comment,
ampersand,
bang,
equal,
greater,
shift_right,
less,
shift_left,
minus,
mod,
pipe,
plus,
slash,
star,
xor,
};
pub fn dump(self: *Tokenizer, token: Token) void {
std.debug.print("\x1b[0;33m{s} \x1b[0;90m\"{s}\"\x1b[0m\n", .{ @tagName(token.tag), token.loc.slice(self.source) });
}
pub fn init(source: [:0]const u8) Tokenizer {
// Skip the UTF-8 BOM if present
const src_start: u32 = if (std.mem.startsWith(u8, source, "\xEF\xBB\xBF")) 3 else 0;
return Tokenizer{
.source = source[src_start..],
.index = 0,
};
}
pub fn peek(self: *Tokenizer) Token {
var index = self.index;
var state = State.start;
var result = Token{
.tag = .eof,
.loc = .{
.start = index,
.end = undefined,
},
};
while (true) : (index += 1) {
const c = self.source[index];
switch (state) {
.start => switch (c) {
0 => {
if (index != self.source.len) {
result.tag = .invalid;
result.loc.start = index;
index += 1;
result.loc.end = index;
return result;
}
break;
},
' ', '\n', '\t', '\r' => result.loc.start = index + 1,
'a'...'z', 'A'...'Z' => state = .ident,
'0'...'9' => state = .number,
'&' => state = .ampersand,
'!' => state = .bang,
'=' => state = .equal,
'>' => state = .greater,
'<' => state = .less,
'-' => state = .minus,
'%' => state = .mod,
'|' => state = .pipe,
'+' => state = .plus,
'/' => state = .slash,
'*' => state = .star,
'_' => state = .underscore,
'^' => state = .xor,
'@' => {
result.tag = .attr;
index += 1;
break;
},
'[' => {
result.tag = .bracket_left;
index += 1;
break;
},
']' => {
result.tag = .bracket_right;
index += 1;
break;
},
'{' => {
result.tag = .brace_left;
index += 1;
break;
},
'}' => {
result.tag = .brace_right;
index += 1;
break;
},
':' => {
result.tag = .colon;
index += 1;
break;
},
',' => {
result.tag = .comma;
index += 1;
break;
},
'(' => {
result.tag = .paren_left;
index += 1;
break;
},
')' => {
result.tag = .paren_right;
index += 1;
break;
},
'.' => {
result.tag = .period;
index += 1;
break;
},
';' => {
result.tag = .semicolon;
index += 1;
break;
},
'~' => {
result.tag = .tilde;
index += 1;
break;
},
else => {
state = .invalid;
result.tag = .invalid;
},
},
.invalid => break,
.ident => switch (c) {
'a'...'z', 'A'...'Z', '0'...'9', '_' => {},
else => {
result.tag = .ident;
if (Token.keywords.get(self.source[result.loc.start..index])) |tag| {
result.tag = tag;
}
break;
},
},
.underscore => switch (c) { // TODO: two underscore `__` https://www.w3.org/TR/WGSL/#identifiers
'a'...'z', 'A'...'Z', '_', '0'...'9' => state = .ident,
else => {
result.tag = .underscore;
break;
},
},
.number => switch (c) {
'0'...'9', '.', 'i', 'u', 'f', 'h', 'e', '-', '+' => {},
else => {
result.tag = .number;
break;
},
},
.block_comment => switch (c) {
0 => break,
'\n' => {
state = .start;
result.loc.start = index + 1;
},
else => {},
},
.ampersand => switch (c) {
'&' => {
result.tag = .and_and;
index += 1;
break;
},
'=' => {
result.tag = .and_equal;
index += 1;
break;
},
else => {
result.tag = .@"and";
break;
},
},
.bang => switch (c) {
'=' => {
result.tag = .not_equal;
index += 1;
break;
},
else => {
result.tag = .bang;
break;
},
},
.equal => switch (c) {
'=' => {
result.tag = .equal_equal;
index += 1;
break;
},
else => {
result.tag = .equal;
break;
},
},
.greater => switch (c) {
'>' => state = .shift_right,
'=' => {
result.tag = .greater_than_equal;
index += 1;
break;
},
else => {
result.tag = .greater_than;
break;
},
},
.shift_right => switch (c) {
'=' => {
result.tag = .shift_right_equal;
index += 1;
break;
},
else => {
result.tag = .shift_right;
break;
},
},
.less => switch (c) {
'<' => state = .shift_left,
'=' => {
result.tag = .less_than_equal;
index += 1;
break;
},
else => {
result.tag = .less_than;
break;
},
},
.shift_left => switch (c) {
'=' => {
result.tag = .shift_left_equal;
index += 1;
break;
},
else => {
result.tag = .shift_left;
break;
},
},
.minus => switch (c) {
'-' => {
result.tag = .minus_minus;
index += 1;
break;
},
'=' => {
result.tag = .minus_equal;
index += 1;
break;
},
'>' => {
result.tag = .arrow;
index += 1;
break;
},
else => {
result.tag = .minus;
break;
},
},
.mod => switch (c) {
'=' => {
result.tag = .modulo_equal;
index += 1;
break;
},
else => {
result.tag = .mod;
break;
},
},
.pipe => switch (c) {
'|' => {
result.tag = .or_or;
index += 1;
break;
},
'=' => {
result.tag = .or_equal;
index += 1;
break;
},
else => {
result.tag = .@"or";
break;
},
},
.plus => switch (c) {
'+' => {
result.tag = .plus_plus;
index += 1;
break;
},
'=' => {
result.tag = .plus_equal;
index += 1;
break;
},
else => {
result.tag = .plus;
break;
},
},
.slash => switch (c) {
'/' => state = .block_comment,
'=' => {
result.tag = .division_equal;
index += 1;
break;
},
else => {
result.tag = .division;
break;
},
},
.star => switch (c) {
'=' => {
result.tag = .times_equal;
index += 1;
break;
},
else => {
result.tag = .star;
break;
},
},
.xor => switch (c) {
'=' => {
result.tag = .xor_equal;
index += 1;
break;
},
else => {
result.tag = .xor;
break;
},
},
}
}
result.loc.end = index;
return result;
}
pub fn next(self: *Tokenizer) Token {
const tok = self.peek();
self.index = tok.loc.end;
return tok;
}
test "tokenize identifier and numbers" {
comptime var str: [:0]const u8 =
\\_ __ _iden iden 100.8i // cc
\\// commnet
\\
;
var tokenizer = Tokenizer.init(str);
try std.testing.expect(tokenizer.next().tag == .underscore);
try std.testing.expect(tokenizer.next().tag == .ident);
try std.testing.expect(tokenizer.next().tag == .ident);
try std.testing.expect(tokenizer.next().tag == .ident);
try std.testing.expect(tokenizer.next().tag == .number);
try std.testing.expect(tokenizer.next().tag == .eof);
}
test "tokenize other" {
comptime var str: [:0]const u8 = "";
inline for (std.meta.fields(Token.Tag), 0..) |field, i| comptime {
if (i > 3) {
str = str ++ " " ++ (Token.Tag.symbol(@intToEnum(Token.Tag, field.value)));
}
};
var tokenizer = Tokenizer.init(str);
comptime var i = 4; // skip identifiers and nums
inline while (i < std.meta.fields(Token.Tag).len) : (i += 1) {
const tag = @intToEnum(Token.Tag, i);
try std.testing.expect(tokenizer.next().tag == tag);
}
try std.testing.expect(tokenizer.next().tag == .eof);
}

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const std = @import("std");
pub const Ast = @import("Ast.zig");
pub const Analyse = @import("Analyse.zig");
pub const Parser = @import("Parser.zig");
pub const Token = @import("Token.zig");
pub const Tokenizer = @import("Tokenizer.zig");
pub const Extension = enum {
f16,
pub const Array = std.enums.EnumArray(Extension, bool);
};
pub const ErrorMsg = struct {
loc: Token.Loc,
msg: []const u8,
note: ?Note,
pub const Note = struct {
loc: ?Token.Loc,
msg: []const u8,
pub fn create(
allocator: std.mem.Allocator,
loc: ?Token.Loc,
comptime format: []const u8,
args: anytype,
) !Note {
return .{
.loc = loc,
.msg = try std.fmt.allocPrint(allocator, comptime format, args),
};
}
pub fn deinit(note: *Note, allocator: std.mem.Allocator) void {
allocator.free(note.msg);
note.* = undefined;
}
};
pub fn create(
allocator: std.mem.Allocator,
loc: Token.Loc,
comptime format: []const u8,
args: anytype,
note: ?Note,
) !ErrorMsg {
return .{
.loc = loc,
.msg = try std.fmt.allocPrint(allocator, comptime format, args),
.note = note,
};
}
pub fn deinit(err_msg: *ErrorMsg, allocator: std.mem.Allocator) void {
if (err_msg.note) |*note| note.*.deinit(allocator);
allocator.free(err_msg.msg);
err_msg.* = undefined;
}
};

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const NUM_PARTICLES: u32 = 1500u;
struct Particle {
pos : vec2<f32>,
vel : vec2<f32>,
}
struct SimParams {
deltaT : f32,
rule1Distance : f32,
rule2Distance : f32,
rule3Distance : f32,
rule1Scale : f32,
rule2Scale : f32,
rule3Scale : f32,
}
struct Particles {
particles : array<Particle>
}
@group(0) @binding(0) var<uniform> params : SimParams;
@group(0) @binding(1) var<storage> particlesSrc : Particles;
@group(0) @binding(2) var<storage,read_write> particlesDst : Particles;
// https://github.com/austinEng/Project6-Vulkan-Flocking/blob/master/data/shaders/computeparticles/particle.comp
@compute @workgroup_size(64)
fn main(@builtin(global_invocation_id) global_invocation_id : vec3<u32>) {
let index : u32 = global_invocation_id.x;
if index >= NUM_PARTICLES {
return;
}
var vPos = particlesSrc.particles[index].pos;
var vVel = particlesSrc.particles[index].vel;
var cMass = vec2<f32>(0.0, 0.0);
var cVel = vec2<f32>(0.0, 0.0);
var colVel = vec2<f32>(0.0, 0.0);
var cMassCount : i32 = 0;
var cVelCount : i32 = 0;
var pos : vec2<f32>;
var vel : vec2<f32>;
var i : u32 = 0u;
loop {
if i >= NUM_PARTICLES {
break;
}
if i == index {
continue;
}
pos = particlesSrc.particles[i].pos;
vel = particlesSrc.particles[i].vel;
if distance(pos, vPos) < params.rule1Distance {
cMass = cMass + pos;
cMassCount = cMassCount + 1;
}
if distance(pos, vPos) < params.rule2Distance {
colVel = colVel - (pos - vPos);
}
if distance(pos, vPos) < params.rule3Distance {
cVel = cVel + vel;
cVelCount = cVelCount + 1;
}
continuing {
i = i + 1u;
}
}
if cMassCount > 0 {
cMass = cMass / f32(cMassCount) - vPos;
}
if cVelCount > 0 {
cVel = cVel / f32(cVelCount);
}
vVel = vVel + (cMass * params.rule1Scale) +
(colVel * params.rule2Scale) +
(cVel * params.rule3Scale);
// clamp velocity for a more pleasing simulation
vVel = normalize(vVel) * clamp(length(vVel), 0.0, 0.1);
// kinematic update
vPos = vPos + (vVel * params.deltaT);
// Wrap around boundary
if vPos.x < -1.0 {
vPos.x = 1.0;
}
if vPos.x > 1.0 {
vPos.x = -1.0;
}
if vPos.y < -1.0 {
vPos.y = 1.0;
}
if vPos.y > 1.0 {
vPos.y = -1.0;
}
// Write back
particlesDst.particles[index].pos = vPos;
particlesDst.particles[index].vel = vVel;
}

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struct FragUniform {
type_: u32,
padding: vec3<f32>,
blend_color: vec4<f32>,
}
@binding(1) @group(0) var<storage> ubos: array<FragUniform>;
@binding(2) @group(0) var mySampler: sampler;
@binding(3) @group(0) var myTexture: texture_2d<f32>;
const wireframe = false;
const antialiased = true;
const aa_px = 1.0; // pixels to consume for AA
const dist_scale_px = 300.0; // TODO: do not hard code
@fragment fn main(
@location(0) uv: vec2<f32>,
@interpolate(linear) @location(1) bary_in: vec2<f32>,
@interpolate(flat) @location(2) triangle_index: u32,
) -> @location(0) vec4<f32> {
// Example 1: Visualize barycentric coordinates:
// let bary = bary_in;
// return vec4<f32>(bary.x, bary.y, 0.0, 1.0);
// return vec4<f32>(0.0, bary.x, 0.0, 1.0); // [1.0 (bottom-left vertex), 0.0 (bottom-right vertex)]
// return vec4<f32>(0.0, bary.y, 0.0, 1.0); // [1.0 (bottom-left vertex), 0.0 (top-right face)]
// Example 2: Very simple quadratic bezier
// let bary = bary_in;
// if (bary.x * bary.x - bary.y) > 0 {
// discard;
// }
// return vec4<f32>(0.0, 1.0, 0.0, 1.0);
// Example 3: Render gkurve primitives
let inversion = select( 1.0, -1.0, ubos[triangle_index].type_ == 0u || ubos[triangle_index].type_ == 1u);
// Texture uvs
var correct_uv = uv;
correct_uv.y = 1.0 - correct_uv.y;
var color = textureSample(myTexture, mySampler, correct_uv) * ubos[triangle_index].blend_color;
// Curve rendering
let border_color = vec4<f32>(1.0, 0.0, 0.0, 1.0);
let border_px = 30.0;
let is_semicircle = ubos[triangle_index].type_ == 1u || ubos[triangle_index].type_ == 3u;
var result = select(
curveColor(bary_in, border_px, border_color, color, inversion, is_semicircle),
color,
ubos[triangle_index].type_ == 4u, // triangle rendering
);
// Wireframe rendering
let wireframe_px = 1.0;
let wireframe_color = vec4<f32>(0.5, 0.5, 0.5, 1.0);
if (wireframe) {
result = wireframeColor(bary_in, wireframe_px, wireframe_color, result);
}
if (result.a == 0.0) { discard; }
return result;
}
// Performs alpha 'over' blending between two premultiplied-alpha colors.
fn alphaOver(a: vec4<f32>, b: vec4<f32>) -> vec4<f32> {
return a + (b * (1.0 - a.a));
}
// Calculates signed distance to a quadratic bézier curve using barycentric coordinates.
fn distanceToQuadratic(bary: vec2<f32>) -> f32 {
// Gradients
let px = dpdx(bary.xy);
let py = dpdy(bary.xy);
// Chain rule
let fx = (2.0 * bary.x) * px.x - px.y;
let fy = (2.0 * bary.x) * py.x - py.y;
return (bary.x * bary.x - bary.y) / sqrt(fx * fx + fy * fy);
}
// Calculates signed distance to a semicircle using barycentric coordinates.
fn distanceToSemicircle(bary: vec2<f32>) -> f32 {
let x = abs(((bary.x - 0.5) * 2.0)); // [0.0 left, 1.0 center, 0.0 right]
let y = ((bary.x-bary.y) * 4.0); // [2.0 bottom, 0.0 top]
let c = x*x + y*y;
// Gradients
let px = dpdx(bary.xy);
let py = dpdy(bary.xy);
// Chain rule
let fx = c * px.x - px.y;
let fy = c * py.x - py.y;
let d = (1.0 - (x*x + y*y)) - 0.2;
return (-d / 6.0) / sqrt(fx * fx + fy * fy);
}
// Calculates signed distance to the wireframe (i.e. faces) of the triangle using barycentric
// coordinates.
fn distanceToWireframe(bary: vec2<f32>) -> f32 {
let normal = vec3<f32>(
bary.y, // distance to right face
(bary.x - bary.y) * 2.0, // distance to bottom face
1.0 - (((bary.x - bary.y)) + bary.x), // distance to left face
);
let fw = sqrt(dpdx(normal)*dpdx(normal) + dpdy(normal)*dpdy(normal));
let d = normal / fw;
return min(min(d.x, d.y), d.z);
}
// Calculates the color of the wireframe, taking into account antialiasing and alpha blending with
// the desired background blend color.
fn wireframeColor(bary: vec2<f32>, px: f32, color: vec4<f32>, blend_color: vec4<f32>) -> vec4<f32> {
let dist = distanceToWireframe(bary);
if (antialiased) {
let outer = dist;
let inner = (px + (aa_px * 2.0)) - dist;
let in_wireframe = outer >= 0.0 && inner >= 0.0;
if (in_wireframe) {
// Note: If this is the outer edge of the wireframe, we do not want to perform alpha
// blending with the background blend color, since it is an antialiased edge and should
// be transparent. However, if it is the internal edge of the wireframe, we do want to
// perform alpha blending as it should be an overlay, not transparent.
let is_outer_edge = outer < inner;
if (is_outer_edge) {
let alpha = smoothstep(0.0, 1.0, outer*(1.0 / aa_px));
return vec4<f32>((color.rgb/color.a)*alpha, alpha);
} else {
let aa_inner = inner - aa_px;
let alpha = smoothstep(0.0, 1.0, aa_inner*(1.0 / aa_px));
let wireframe_color = vec4<f32>((color.rgb/color.a)*alpha, alpha);
return alphaOver(wireframe_color, blend_color);
}
}
return blend_color;
} else {
// If we're at the edge use the wireframe color, otherwise use the background blend_color.
return select(blend_color, color, (px - dist) >= 0.0);
}
}
// Calculates the color for a curve, taking into account antialiasing and alpha blending with
// the desired background blend color.
//
// inversion: concave (-1.0) or convex (1.0)
// is_semicircle: quadratic bezier (false) or semicircle (true)
fn curveColor(
bary: vec2<f32>,
border_px: f32,
border_color: vec4<f32>,
blend_color: vec4<f32>,
inversion: f32,
is_semicircle: bool,
) -> vec4<f32> {
let dist = select(
distanceToQuadratic(bary),
distanceToSemicircle(bary),
is_semicircle,
) * inversion;
let is_inverted = (inversion + 1.0) / 2.0; // 1.0 if inverted, 0.0 otherwise
if (antialiased) {
let outer = dist + ((border_px + (aa_px * 2.0)) * is_inverted); // bottom
let inner = ((border_px + (aa_px * 2.0)) * (1.0-is_inverted)) - dist; // top
let in_border = outer >= 0.0 && inner >= 0.0;
if (in_border) {
// Note: If this is the outer edge of the curve, we do not want to perform alpha
// blending with the background blend color, since it is an antialiased edge and should
// be transparent. However, if it is the internal edge of the curve, we do want to
// perform alpha blending as it should be an overlay, not transparent.
let is_outer_edge = outer < inner;
if (is_outer_edge) {
let aa_outer = outer - (aa_px * is_inverted);
let alpha = smoothstep(0.0, 1.0, aa_outer*(1.0 / aa_px));
return vec4<f32>((border_color.rgb/border_color.a)*alpha, alpha);
} else {
let aa_inner = inner - (aa_px * (1.0 - is_inverted));
let alpha = smoothstep(0.0, 1.0, aa_inner*(1.0 / aa_px));
let new_border_color = vec4<f32>((border_color.rgb/border_color.a)*alpha, alpha);
return alphaOver(new_border_color, blend_color);
}
return border_color;
} else if (outer >= 0.0) {
return blend_color;
} else {
return vec4<f32>(0.0);
}
} else {
let outer = dist + (border_px * is_inverted);
let inner = (border_px * (1.0-is_inverted)) - dist;
let in_border = outer >= 0.0 && inner >= 0.0;
if (in_border) {
return border_color;
} else if (outer >= 0.0) {
return blend_color;
} else {
return vec4<f32>(0.0);
}
}
}

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const std = @import("std");
const dusk = @import("dusk");
const expect = std.testing.expect;
const allocator = std.testing.allocator;
fn sdkPath(comptime suffix: []const u8) []const u8 {
if (suffix[0] != '/') @compileError("suffix must be an absolute path");
return comptime blk: {
const root_dir = std.fs.path.dirname(@src().file) orelse ".";
break :blk root_dir ++ suffix;
};
}
// TODO: move this to cli/main.zig
pub fn printErrors(errors: []dusk.ErrorMsg, source: []const u8, file_path: ?[]const u8) !void {
var bw = std.io.bufferedWriter(std.io.getStdErr().writer());
const b = bw.writer();
const term = std.debug.TTY.Config{ .escape_codes = {} };
for (errors) |*err| {
defer err.deinit(allocator);
const loc_extra = err.loc.extraInfo(source);
// 'file:line:column error: <MSG>'
try term.setColor(b, .Bold);
try b.print("{?s}:{d}:{d} ", .{ file_path, loc_extra.line, loc_extra.col });
try term.setColor(b, .Red);
try b.writeAll("error: ");
try term.setColor(b, .Reset);
try term.setColor(b, .Bold);
try b.writeAll(err.msg);
try b.writeByte('\n');
try printCode(b, term, source, err.loc);
// note
if (err.note) |note| {
if (note.loc) |note_loc| {
const note_loc_extra = note_loc.extraInfo(source);
try term.setColor(b, .Reset);
try term.setColor(b, .Bold);
try b.print("{?s}:{d}:{d} ", .{ file_path, note_loc_extra.line, note_loc_extra.col });
}
try term.setColor(b, .Cyan);
try b.writeAll("note: ");
try term.setColor(b, .Reset);
try term.setColor(b, .Bold);
try b.writeAll(note.msg);
try b.writeByte('\n');
if (note.loc) |note_loc| {
try printCode(b, term, source, note_loc);
}
}
try term.setColor(b, .Reset);
}
try bw.flush();
}
fn printCode(writer: anytype, term: std.debug.TTY.Config, source: []const u8, loc: dusk.Token.Loc) !void {
const loc_extra = loc.extraInfo(source);
try term.setColor(writer, .Dim);
try writer.print("{d} │ ", .{loc_extra.line});
try term.setColor(writer, .Reset);
try writer.writeAll(source[loc_extra.line_start..loc.start]);
try term.setColor(writer, .Green);
try writer.writeAll(source[loc.start..loc.end]);
try term.setColor(writer, .Reset);
try writer.writeAll(source[loc.end..loc_extra.line_end]);
try writer.writeByte('\n');
// location pointer
const line_number_len = (std.math.log10(loc_extra.line) + 1) + 3;
try writer.writeByteNTimes(
' ',
line_number_len + (loc_extra.col - 1),
);
try term.setColor(writer, .Bold);
try term.setColor(writer, .Green);
try writer.writeByte('^');
try writer.writeByteNTimes('~', loc.end - loc.start - 1);
try writer.writeByte('\n');
}
fn expectTree(source: [:0]const u8) !dusk.Ast {
var res = try dusk.Ast.parse(allocator, source);
switch (res) {
.tree => |*tree| {
errdefer tree.deinit(allocator);
if (try tree.analyse(allocator)) |errors| {
try printErrors(errors, source, null);
allocator.free(errors);
return error.Analysing;
}
return tree.*;
},
.errors => |err_msgs| {
try printErrors(err_msgs, source, null);
allocator.free(err_msgs);
return error.Parsing;
},
}
}
test "empty" {
const source = "";
var tree = try expectTree(source);
defer tree.deinit(allocator);
}
test "boids" {
const source = @embedFile("boids.wgsl");
var tree = try expectTree(source);
defer tree.deinit(allocator);
}
test "gkurve" {
if (true) return error.SkipZigTest;
const source = @embedFile("gkurve.wgsl");
var tree = try expectTree(source);
defer tree.deinit(allocator);
}
test "variable & expressions" {
const source = "var expr = 1 + 5 + 2 * 3 > 6 >> 7;";
var tree = try expectTree(source);
defer tree.deinit(allocator);
const root_node = 0;
try expect(tree.nodeLHS(root_node) + 1 == tree.nodeRHS(root_node));
const variable = tree.spanToList(root_node)[0];
const variable_name = tree.tokenLoc(tree.extraData(dusk.Ast.Node.GlobalVarDecl, tree.nodeLHS(variable)).name);
try expect(std.mem.eql(u8, "expr", variable_name.slice(source)));
try expect(tree.nodeTag(variable) == .global_variable);
try expect(tree.tokenTag(tree.nodeToken(variable)) == .k_var);
const expr = tree.nodeRHS(variable);
try expect(tree.nodeTag(expr) == .greater);
const @"1 + 5 + 2 * 3" = tree.nodeLHS(expr);
try expect(tree.nodeTag(@"1 + 5 + 2 * 3") == .add);
const @"1 + 5" = tree.nodeLHS(@"1 + 5 + 2 * 3");
try expect(tree.nodeTag(@"1 + 5") == .add);
const @"1" = tree.nodeLHS(@"1 + 5");
try expect(tree.nodeTag(@"1") == .number_literal);
const @"5" = tree.nodeRHS(@"1 + 5");
try expect(tree.nodeTag(@"5") == .number_literal);
const @"2 * 3" = tree.nodeRHS(@"1 + 5 + 2 * 3");
try expect(tree.nodeTag(@"2 * 3") == .mul);
const @"6 >> 7" = tree.nodeRHS(expr);
try expect(tree.nodeTag(@"6 >> 7") == .shift_right);
const @"6" = tree.nodeLHS(@"6 >> 7");
try expect(tree.nodeTag(@"6") == .number_literal);
const @"7" = tree.nodeRHS(@"6 >> 7");
try expect(tree.nodeTag(@"7") == .number_literal);
}