From ac81ff714a9b0c959851105bb7efce6035bcdeb3 Mon Sep 17 00:00:00 2001 From: Marto Date: Fri, 23 Jan 2026 21:16:06 +0100 Subject: [PATCH] Initial commit --- .gitignore | 3 + build.zig | 168 +++++++++++++++++++++++ build.zig.zon | 48 +++++++ src/main.zig | 37 +++++ src/structures/internal/base_structs.zig | 5 + src/structures/internal/triangle.zig | 79 +++++++++++ src/structures/structures.zig | 2 + 7 files changed, 342 insertions(+) create mode 100644 .gitignore create mode 100644 build.zig create mode 100644 build.zig.zon create mode 100644 src/main.zig create mode 100644 src/structures/internal/base_structs.zig create mode 100644 src/structures/internal/triangle.zig create mode 100644 src/structures/structures.zig diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..f7a0f27 --- /dev/null +++ b/.gitignore @@ -0,0 +1,3 @@ +/.zig-cache +/.idea +/zig-out diff --git a/build.zig b/build.zig new file mode 100644 index 0000000..b943d2c --- /dev/null +++ b/build.zig @@ -0,0 +1,168 @@ +const std = @import("std"); + +// Although this function looks imperative, it does not perform the build +// directly and instead it mutates the build graph (`b`) that will be then +// executed by an external runner. The functions in `std.Build` implement a DSL +// for defining build steps and express dependencies between them, allowing the +// build runner to parallelize the build automatically (and the cache system to +// know when a step doesn't need to be re-run). +pub fn build(b: *std.Build) void { + // Standard target options allow the person running `zig build` to choose + // what target to build for. Here we do not override the defaults, which + // means any target is allowed, and the default is native. Other options + // for restricting supported target set are available. + const target = b.standardTargetOptions(.{}); + // Standard optimization options allow the person running `zig build` to select + // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not + // set a preferred release mode, allowing the user to decide how to optimize. + const optimize = b.standardOptimizeOption(.{}); + // It's also possible to define more custom flags to toggle optional features + // of this build script using `b.option()`. All defined flags (including + // target and optimize options) will be listed when running `zig build --help` + // in this directory. + + // This creates a module, which represents a collection of source files alongside + // some compilation options, such as optimization mode and linked system libraries. + // Zig modules are the preferred way of making Zig code available to consumers. + // addModule defines a module that we intend to make available for importing + // to our consumers. We must give it a name because a Zig package can expose + // multiple modules and consumers will need to be able to specify which + // module they want to access. + // const mod = b.addModule("rasteriser", .{ + // // The root source file is the "entry point" of this module. Users of + // // this module will only be able to access public declarations contained + // // in this file, which means that if you have declarations that you + // // intend to expose to consumers that were defined in other files part + // // of this module, you will have to make sure to re-export them from + // // the root file. + // .root_source_file = b.path("src/root.zig"), + // // Later on we'll use this module as the root module of a test executable + // // which requires us to specify a target. + // .target = target, + // }); + + const raylib_dep = b.dependency("raylib_zig", .{ + .target = target, + .optimize = optimize, + }); + + const raylib = raylib_dep.module("raylib"); + const raylib_artifact = raylib_dep.artifact("raylib"); + + // Here we define an executable. An executable needs to have a root module + // which needs to expose a `main` function. While we could add a main function + // to the module defined above, it's sometimes preferable to split business + // logic and the CLI into two separate modules. + // + // If your goal is to create a Zig library for others to use, consider if + // it might benefit from also exposing a CLI tool. A parser library for a + // data serialization format could also bundle a CLI syntax checker, for example. + // + // If instead your goal is to create an executable, consider if users might + // be interested in also being able to embed the core functionality of your + // program in their own executable in order to avoid the overhead involved in + // subprocessing your CLI tool. + // + // If neither case applies to you, feel free to delete the declaration you + // don't need and to put everything under a single module. + const exe = b.addExecutable(.{ + .name = "rasteriser", + .root_module = b.createModule(.{ + // b.createModule defines a new module just like b.addModule but, + // unlike b.addModule, it does not expose the module to consumers of + // this package, which is why in this case we don't have to give it a name. + .root_source_file = b.path("src/main.zig"), + // Target and optimization levels must be explicitly wired in when + // defining an executable or library (in the root module), and you + // can also hardcode a specific target for an executable or library + // definition if desireable (e.g. firmware for embedded devices). + .target = target, + .optimize = optimize, + // List of modules available for import in source files part of the + // root module. + .imports = &.{ + // Here "rasteriser" is the name you will use in your source code to + // import this module (e.g. `@import("rasteriser")`). The name is + // repeated because you are allowed to rename your imports, which + // can be extremely useful in case of collisions (which can happen + // importing modules from different packages). + // .{ .name = "rasteriser", .module = mod }, + + .{ .name = "raylib", .module = raylib}, + }, + }), + }); + + exe.linkLibrary(raylib_artifact); + + // This declares intent for the executable to be installed into the + // install prefix when running `zig build` (i.e. when executing the default + // step). By default the install prefix is `zig-out/` but can be overridden + // by passing `--prefix` or `-p`. + b.installArtifact(exe); + + // This creates a top level step. Top level steps have a name and can be + // invoked by name when running `zig build` (e.g. `zig build run`). + // This will evaluate the `run` step rather than the default step. + // For a top level step to actually do something, it must depend on other + // steps (e.g. a Run step, as we will see in a moment). + const run_step = b.step("run", "Run the app"); + + // This creates a RunArtifact step in the build graph. A RunArtifact step + // invokes an executable compiled by Zig. Steps will only be executed by the + // runner if invoked directly by the user (in the case of top level steps) + // or if another step depends on it, so it's up to you to define when and + // how this Run step will be executed. In our case we want to run it when + // the user runs `zig build run`, so we create a dependency link. + const run_cmd = b.addRunArtifact(exe); + run_step.dependOn(&run_cmd.step); + + // By making the run step depend on the default step, it will be run from the + // installation directory rather than directly from within the cache directory. + run_cmd.step.dependOn(b.getInstallStep()); + + // This allows the user to pass arguments to the application in the build + // command itself, like this: `zig build run -- arg1 arg2 etc` + if (b.args) |args| { + run_cmd.addArgs(args); + } + + // Creates an executable that will run `test` blocks from the provided module. + // Here `mod` needs to define a target, which is why earlier we made sure to + // set the releative field. + // const mod_tests = b.addTest(.{ + // .root_module = mod, + // }); + + // A run step that will run the test executable. + // const run_mod_tests = b.addRunArtifact(mod_tests); + + // Creates an executable that will run `test` blocks from the executable's + // root module. Note that test executables only test one module at a time, + // hence why we have to create two separate ones. + const exe_tests = b.addTest(.{ + .root_module = exe.root_module, + }); + + // A run step that will run the second test executable. + const run_exe_tests = b.addRunArtifact(exe_tests); + + // A top level step for running all tests. dependOn can be called multiple + // times and since the two run steps do not depend on one another, this will + // make the two of them run in parallel. + const test_step = b.step("test", "Run tests"); + // test_step.dependOn(&run_mod_tests.step); + test_step.dependOn(&run_exe_tests.step); + + // Just like flags, top level steps are also listed in the `--help` menu. + // + // The Zig build system is entirely implemented in userland, which means + // that it cannot hook into private compiler APIs. All compilation work + // orchestrated by the build system will result in other Zig compiler + // subcommands being invoked with the right flags defined. You can observe + // these invocations when one fails (or you pass a flag to increase + // verbosity) to validate assumptions and diagnose problems. + // + // Lastly, the Zig build system is relatively simple and self-contained, + // and reading its source code will allow you to master it. +} diff --git a/build.zig.zon b/build.zig.zon new file mode 100644 index 0000000..a7717ca --- /dev/null +++ b/build.zig.zon @@ -0,0 +1,48 @@ +.{ + // This is the default name used by packages depending on this one. For + // example, when a user runs `zig fetch --save `, this field is used + // as the key in the `dependencies` table. Although the user can choose a + // different name, most users will stick with this provided value. + // + // It is redundant to include "zig" in this name because it is already + // within the Zig package namespace. + .name = .rasteriser, + // This is a [Semantic Version](https://semver.org/). + // In a future version of Zig it will be used for package deduplication. + .version = "0.0.0", + // Together with name, this represents a globally unique package + // identifier. This field is generated by the Zig toolchain when the + // package is first created, and then *never changes*. This allows + // unambiguous detection of one package being an updated version of + // another. + // + // When forking a Zig project, this id should be regenerated (delete the + // field and run `zig build`) if the upstream project is still maintained. + // Otherwise, the fork is *hostile*, attempting to take control over the + // original project's identity. Thus it is recommended to leave the comment + // on the following line intact, so that it shows up in code reviews that + // modify the field. + .fingerprint = 0xde5064b97e2d76b, // Changing this has security and trust implications. + // Tracks the earliest Zig version that the package considers to be a + // supported use case. + .minimum_zig_version = "0.15.2", + // This field is optional. + // Each dependency must either provide a `url` and `hash`, or a `path`. + // `zig build --fetch` can be used to fetch all dependencies of a package, recursively. + // Once all dependencies are fetched, `zig build` no longer requires + // internet connectivity. + .dependencies = .{ + .raylib_zig = .{ + .url = "git+https://github.com/raylib-zig/raylib-zig?ref=devel#7d4761b878f43671024ce197f721827b5355a67e", + .hash = "raylib_zig-5.6.0-dev-KE8REGlNBQDR7NML06VBtT7gP3VZNY70E5WohAxzqrNn", + }, + }, + .paths = .{ + "build.zig", + "build.zig.zon", + "src", + // For example... + //"LICENSE", + //"README.md", + }, +} diff --git a/src/main.zig b/src/main.zig new file mode 100644 index 0000000..e876d76 --- /dev/null +++ b/src/main.zig @@ -0,0 +1,37 @@ +const std = @import("std"); +const rl = @import("raylib"); +const structures = @import("structures/structures.zig"); + +pub fn main() !void { + const screen = .{.width = 800, .height = 600}; + rl.initWindow(screen.width, screen.height, "Rasteriser"); + defer rl.closeWindow(); + + rl.setTargetFPS(60); + + const point_a = rl.Vector2 {.x = 50, .y = 550}; // A + const point_b = rl.Vector2 {.x = 750, .y = 550}; // B + const point_c = rl.Vector2 {.x = 400, .y = 100}; // C + + var triangle = structures.Triangle.new(point_a, point_b, point_c); + const range = triangle.getCoordsLimit(); + + while (!rl.windowShouldClose()) { + rl.beginDrawing(); + defer rl.endDrawing(); + + rl.clearBackground(.gray); + + for (range.y.min..range.y.max+1) |y| { + for (range.x.min..range.x.max+1) |x| { + const point = rl.Vector2 { + .x = @floatFromInt(x), + .y = @floatFromInt(y), + }; + + const colour = triangle.pixelColour(point) orelse continue; + rl.drawPixelV(point, colour); + } + } + } +} \ No newline at end of file diff --git a/src/structures/internal/base_structs.zig b/src/structures/internal/base_structs.zig new file mode 100644 index 0000000..710c8e4 --- /dev/null +++ b/src/structures/internal/base_structs.zig @@ -0,0 +1,5 @@ +/// Tracks minimum and maximum possible x/y coordinate of the triangle (or any other object we wish to render) +pub const MinMaxLimit = struct{ + x: struct{min: usize, max: usize}, + y: struct{min: usize, max: usize}, +}; \ No newline at end of file diff --git a/src/structures/internal/triangle.zig b/src/structures/internal/triangle.zig new file mode 100644 index 0000000..8e308e0 --- /dev/null +++ b/src/structures/internal/triangle.zig @@ -0,0 +1,79 @@ +const rl = @import("raylib"); +const BaseStructures = @import("base_structs.zig"); + +pub const Triangle = struct { + point_a: rl.Vector2, + point_b: rl.Vector2, + point_c: rl.Vector2, + + /// Constructor + pub fn new(point_a: rl.Vector2, point_b: rl.Vector2, point_c: rl.Vector2) Triangle { + return .{ + .point_a = point_a, + .point_b = point_b, + .point_c = point_c, + }; + } + + /// Calculates the pixel colour or returns null if the pixle is not within the triangle + pub fn pixelColour(self: *Triangle, point: rl.Vector2) ?rl.Color { + const acp = edgeFunction(self.point_a, self.point_c, point); + const cbp = edgeFunction(self.point_c, self.point_b, point); + const apb = edgeFunction(self.point_a, point, self.point_b); + if (acp < 0 or cbp < 0 or apb < 0) return null; + + // normalize values + const abc = edgeFunction(self.point_a, self.point_c, self.point_b); + // a red, b blue, c green + const weight_a = cbp / abc; + const weight_b = acp / abc; + const weight_c = apb / abc; + + const colour_a = rl.Vector3 { + .x = @floatFromInt(rl.Color.red.r), + .y = @floatFromInt(rl.Color.red.g), + .z = @floatFromInt(rl.Color.red.b), + }; + const colour_b = rl.Vector3 { + .x = @floatFromInt(rl.Color.blue.r), + .y = @floatFromInt(rl.Color.blue.g), + .z = @floatFromInt(rl.Color.blue.b), + }; + const colour_c = rl.Vector3 { + .x = @floatFromInt(rl.Color.green.r), + .y = @floatFromInt(rl.Color.green.g), + .z = @floatFromInt(rl.Color.green.b), + }; + + // craft colours + const r = colour_a.x * weight_a + colour_b.x * weight_b + colour_c.x * weight_c; + const g = colour_a.y * weight_a + colour_b.y * weight_b + colour_c.y * weight_c; + const b = colour_a.z * weight_a + colour_b.z * weight_b + colour_c.z * weight_c; + + return .{ + .r = @intFromFloat(r), + .g = @intFromFloat(g), + .b = @intFromFloat(b), + .a = 255, + }; + } + + /// Calculates point's orientation + fn edgeFunction(a: rl.Vector2, b: rl.Vector2, c: rl.Vector2) f32 { + return (b.x - a.x) * (c.y - a.y) - (b.y - a.y) * (c.x - a.x); + } + + /// Returns what the triangle's minimum and maximum x and y are + pub fn getCoordsLimit(self: *Triangle) BaseStructures.MinMaxLimit { + return .{ + .x = .{ + .min = @intFromFloat(@min(self.point_a.x, self.point_b.x, self.point_c.x)), + .max = @intFromFloat(@max(self.point_a.x, self.point_b.x, self.point_c.x)), + }, + .y = .{ + .min = @intFromFloat(@min(self.point_a.y, self.point_b.y, self.point_c.y)), + .max = @intFromFloat(@max(self.point_a.y, self.point_b.y, self.point_c.y)), + } + }; + } +}; \ No newline at end of file diff --git a/src/structures/structures.zig b/src/structures/structures.zig new file mode 100644 index 0000000..20b42fe --- /dev/null +++ b/src/structures/structures.zig @@ -0,0 +1,2 @@ +pub const Triangle = @import("internal/triangle.zig").Triangle; +pub const BaseStr = @import("internal/base_structs.zig"); \ No newline at end of file