model3d: add m3d implementation / bindings (#589)

libs/model3d/build.zig

@@ -0,0 +1,36 @@
+const std = @import("std");
+
+pub const pkg = std.build.Pkg{
+    .name = "model3d",
+    .source = .{ .path = sdkPath("/src/main.zig") },
+};
+
+pub fn build(b: *std.build.Builder) void {
+    const mode = b.standardReleaseOptions();
+    const target = b.standardTargetOptions(.{});
+    const test_step = b.step("test", "Run library tests");
+    test_step.dependOn(&testStep(b, mode, target).step);
+}
+
+pub fn testStep(b: *std.build.Builder, mode: std.builtin.Mode, target: std.zig.CrossTarget) *std.build.RunStep {
+    const main_tests = b.addTestExe("model3d-tests", "src/main.zig");
+    main_tests.setBuildMode(mode);
+    main_tests.setTarget(target);
+    link(main_tests);
+    main_tests.install();
+    return main_tests.run();
+}
+
+pub fn link(step: *std.build.LibExeObjStep) void {
+    step.addCSourceFile(sdkPath("/src/c/m3d.c"), &.{});
+    step.addIncludePath(sdkPath("/src/c"));
+    step.linkLibC();
+}
+
+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;
+    };
+}

libs/model3d/src/c/m3d.c

@@ -0,0 +1,3 @@
+#define M3D_IMPLEMENTATION
+#define M3D_EXPORTER
+#include "m3d.h"

libs/model3d/src/main.zig

@@ -0,0 +1,231 @@
+const std = @import("std");
+const c = @cImport(@cInclude("m3d.h"));
+const testing = std.testing;
+
+pub const Error = error{
+    /// memory allocation error
+    OutOfMemory,
+    /// malformed text file (ASCII import only)
+    BadFile,
+    /// unimplemented interpreter (procedural surface)
+    Unimplemented,
+    /// unknown material property record
+    Unknown,
+    /// unknown mesh record (only triangles supported)
+    UnknownMeshRecord,
+    /// unknown image format (PNG only)
+    UnknownImageFormat,
+    /// unknown action or frame or missing bones
+    UnknownActionFrame,
+    /// unknown shape command record
+    UnknownCommand,
+    /// no voxel dimension or voxel size defined
+    UnknownVoxel,
+    /// either the precision or number of bones truncated
+    Truncated,
+    /// too many or no chunk of color map
+    UnexpectedColorMapCount,
+    /// too many or no chunk of texture map
+    UnexpectedTextureMapCount,
+    /// too many or no chunk of vertices
+    UnexpectedVerticeCount,
+    /// too many or no chunk of bones
+    UnexpectedBoneCount,
+    /// too many or no chunk of material
+    UnexpectedMaterialCount,
+    /// too many or no chunk of shape
+    UnexpectedShapeCount,
+    /// too many or no chunk of voxel
+    UnexpectedVoxelCount,
+};
+
+const M3d = @This();
+
+handle: *c.m3d_t,
+
+pub fn load(data: [:0]u8, readfile_fn: ?ReadFn, free_fn: ?FreeFn, mtllib: ?M3d) ?M3d {
+    return .{
+        .handle = c.m3d_load(
+            data.ptr,
+            readfile_fn,
+            free_fn,
+            if (mtllib) |m| m.handle else null,
+        ) orelse return null,
+    };
+}
+
+pub fn deinit(self: M3d) void {
+    c.m3d_free(self.handle);
+}
+
+/// return value must be freed with c_allocator
+pub fn save(self: M3d, quality: Quality, flags: Flags) Error![]u8 {
+    var size: u32 = 0;
+    return if (c.m3d_save(
+        self.handle,
+        @enumToInt(quality),
+        @bitCast(c_int, flags),
+        &size,
+    )) |res|
+        res[0..size]
+    else
+        return intToError(self.errCode());
+}
+
+pub fn frame(self: M3d, action_id: u32, frame_id: u32, skeleton: []Transform) Error![]Transform {
+    return if (c.m3d_frame(self.handle, action_id, frame_id, skeleton.ptr)) |res|
+        res[0..self.handle.numbone]
+    else
+        intToError(self.errCode());
+}
+
+pub fn pose(self: M3d, action_id: u32, msec: u32) Error![]Bone {
+    return if (c.m3d_pose(self.handle, action_id, msec)) |res|
+        res[0..self.handle.numbone]
+    else
+        intToError(self.errCode());
+}
+
+pub fn name(self: M3d) [:0]const u8 {
+    return std.mem.span(self.handle.name);
+}
+
+pub fn license(self: M3d) [:0]const u8 {
+    return std.mem.span(self.handle.license);
+}
+
+pub fn author(self: M3d) [:0]const u8 {
+    return std.mem.span(self.handle.author);
+}
+
+pub fn description(self: M3d) [:0]const u8 {
+    return std.mem.span(self.handle.desc);
+}
+
+pub fn scale(self: M3d) f32 {
+    return self.handle.scale;
+}
+
+pub fn preview(self: M3d) InlineAsset {
+    return self.handle.preview;
+}
+
+pub fn textures(self: M3d) []TextureData {
+    return self.handle.texture[0..self.handle.numtexture];
+}
+
+pub fn materials(self: M3d) []Material {
+    return self.handle.material[0..self.handle.nummaterial];
+}
+
+pub fn errCode(self: M3d) c_int {
+    return self.handle.errcode;
+}
+
+pub const TextureIndex = c.m3d_texturedata_t;
+pub const TextureData = c.m3d_texturedata_t;
+pub const Weight = c.m3d_weight_t;
+pub const Skin = c.m3d_skin_t;
+pub const Bone = c.m3d_bone_t;
+pub const Vertex = c.m3d_vertex_t;
+pub const Material = c.m3d_material_t;
+pub const Face = c.m3d_face_t;
+pub const VoxelItem = c.m3d_voxelitem_t;
+pub const VoxelType = c.m3d_voxeltype_t;
+pub const Voxel = c.m3d_voxel_t;
+pub const ShapeCommand = c.m3d_shapecommand_t;
+pub const Shape = c.m3d_shape_t;
+pub const Label = c.m3d_label_t;
+pub const Transform = c.m3d_transform_t;
+pub const Frame = c.m3d_frame_t;
+pub const Action = c.m3d_action_t;
+pub const InlineAsset = c.m3d_inlinedasset_t;
+pub const ReadFn = *const fn (filename: [*c]u8, size: [*c]c_uint) callconv(.C) [*c]u8;
+pub const FreeFn = *const fn (ptr: ?*anyopaque) callconv(.C) void;
+
+pub const Quality = enum(u2) {
+    // export with -128 to 127 coordinate precision
+    int8 = c.M3D_EXP_INT8,
+    // export with -32768 to 32767 precision
+    int16 = c.M3D_EXP_INT16,
+    // export with 32 bit floating point precision
+    float = c.M3D_EXP_FLOAT,
+    // export with 64 bit floatint point precision
+    double = c.M3D_EXP_DOUBLE,
+};
+
+pub const Flags = packed struct {
+    // don't export color map
+    nocmap: bool = false,
+    // don't export materials
+    nomaterial: bool = false,
+    // don't export model face
+    noface: bool = false,
+    // don't export normal vectors
+    nonormal: bool = false,
+    // don't export texture UV
+    notxtcrd: bool = false,
+    // flip V in texture UVs
+    fliptxtcrd: bool = false,
+    // don't recalculate coordinates
+    norecalc: bool = false,
+    // the input is left-handed
+    idosuck: bool = false,
+    // don't export skeleton
+    nobone: bool = false,
+    // no animation nor skeleton saved
+    noaction: bool = false,
+    // inline assets into the model
+    inline_assets: bool = false,
+    // export unknown chunks too
+    extra: bool = false,
+    // export into uncompressed binary
+    nozlib: bool = false,
+    // export into ASCII format
+    ascii: bool = false,
+    // don't export maximum vertex
+    novrtmax: bool = false,
+
+    _padding: u17 = 0,
+};
+
+fn intToError(int: c_int) Error {
+    return switch (int) {
+        c.M3D_SUCCESS => unreachable,
+        c.M3D_ERR_ALLOC => error.OutOfMemory,
+        c.M3D_ERR_BADFILE => error.BadFile,
+        c.M3D_ERR_UNIMPL => error.Unimplemented,
+        c.M3D_ERR_UNKPROP => error.Unknown,
+        c.M3D_ERR_UNKMESH => error.UnknownMeshRecord,
+        c.M3D_ERR_UNKIMG => error.UnknownImageFormat,
+        c.M3D_ERR_UNKFRAME => error.UnknownActionFrame,
+        c.M3D_ERR_UNKCMD => error.UnknownCommand,
+        c.M3D_ERR_UNKVOX => error.UnknownVoxel,
+        c.M3D_ERR_TRUNC => error.Truncated,
+        c.M3D_ERR_CMAP => error.UnexpectedColorMapCount,
+        c.M3D_ERR_TMAP => error.UnexpectedTextureMapCount,
+        c.M3D_ERR_VRTS => error.UnexpectedVerticeCount,
+        c.M3D_ERR_BONE => error.UnexpectedBoneCount,
+        c.M3D_ERR_MTRL => error.UnexpectedMaterialCount,
+        c.M3D_ERR_SHPE => error.UnexpectedShapeCount,
+        c.M3D_ERR_VOXT => error.UnexpectedVoxelCount,
+        else => unreachable,
+    };
+}
+
+test {
+    testing.refAllDeclsRecursive(@This());
+
+    var model_file = try std.fs.cwd().openFile("assets/cube.m3d", .{});
+    defer model_file.close();
+    var model_data = try model_file.readToEndAllocOptions(testing.allocator, 1024, 119, @alignOf(u8), 0);
+    defer testing.allocator.free(model_data);
+
+    const model = M3d.load(model_data, null, null, null) orelse return error.Fail;
+    defer model.deinit();
+    try testing.expectEqualStrings(model.name(), "cube.obj");
+
+    var out = try model.save(.float, .{});
+    defer std.heap.c_allocator.free(out);
+    try testing.expect(out.len >= 119);
+}