Adds SDL3 backend

README.md

@@ -18,7 +18,9 @@ The static library for Dear ImGui, and supported backends, are provided as artif
 
 ## How to use the backends
 
-Right now, this package only exports the Vulkan backend: `dear_imgui_vulkan`.
+Right now, this package only exports the following backends:
+* `dear_imgui_vulkan`
+* `dear_imgui_sdl3`
 
 Contributions are welcome if you'd like to add others. The process should be fairly straightforward.
 

build.zig

@@ -69,6 +69,26 @@ pub fn build(b: *std.Build) void {
     dear_imgui_vulkan_lib.installHeadersDirectory(vulkan_headers.path("include"), "", .{});
     b.installArtifact(dear_imgui_vulkan_lib);
 
+    // Compile the SDL3 backend as a static library
+    const dear_imgui_sdl3_lib = b.addLibrary(.{
+        .name = "dear_imgui_vulkan",
+        .root_module = b.createModule(.{
+            .target = target,
+            .optimize = optimize_external,
+        }),
+    });
+    dear_imgui_sdl3_lib.linkLibrary(dear_imgui_lib);
+    dear_imgui_sdl3_lib.addCSourceFile(.{ .file = upstream.path("backends/imgui_impl_sdl3.cpp"), .flags = flags });
+    dear_imgui_sdl3_lib.addCSourceFile(.{ .file = b.path("src/cached/dcimgui_impl_sdl3.cpp"), .flags = flags });
+    dear_imgui_sdl3_lib.addIncludePath(upstream.path(""));
+    dear_imgui_sdl3_lib.addIncludePath(upstream.path("backends"));
+    const sdl = b.dependency("sdl", .{});
+    dear_imgui_sdl3_lib.addIncludePath(sdl.path("include"));
+    // dear_imgui_sdl3_lib.root_module.addCMacro("IMGUI_IMPL_VULKAN_NO_PROTOTYPES", "1"); // Assumed in generator // XXX: ...
+    dear_imgui_sdl3_lib.installHeadersDirectory(upstream.path("backends"), "", .{});
+    // dear_imgui_sdl3_lib.installHeadersDirectory(vulkan_headers.path("include"), "", .{}); // XXX: ...
+    b.installArtifact(dear_imgui_sdl3_lib);
+
     // Compile the generator
     const generate_exe = b.addExecutable(.{
         .name = "generate",
@@ -114,4 +134,17 @@ pub fn build(b: *std.Build) void {
     });
     dear_imgui_vulkan_zig_module.linkLibrary(dear_imgui_vulkan_lib);
     dear_imgui_vulkan_zig_module.addImport("dear_imgui", dear_imgui_zig_module);
+
+    // Generate Zig bindings for the SDL3 backend
+    const generate_sdl3 = b.addRunArtifact(generate_exe);
+    generate_sdl3.addFileArg(b.path("src/cached/dcimgui_impl_sdl3.json"));
+    const dear_imgui_sdl3_zig = generate_sdl3.addOutputFileArg("dear_imgui_impl_sdl3.zig");
+    generate_sdl3.addFileArg(b.path("src/templates/impl_sdl3_prefix.zig.template"));
+    generate_sdl3.addFileArg(b.path("src/templates/impl_sdl3_postfix.zig.template"));
+    const dear_imgui_sdl3_zig_module = b.addModule("dear_imgui_sdl3", .{
+        .root_source_file = dear_imgui_sdl3_zig,
+        .target = target,
+        .optimize = optimize,
+    });
+    dear_imgui_sdl3_zig_module.linkLibrary(dear_imgui_sdl3_lib);
 }

build.zig.zon

@@ -12,6 +12,11 @@
             .url = "https://github.com/KhronosGroup/Vulkan-Headers/archive/refs/tags/v1.4.313.tar.gz",
             .hash = "N-V-__8AAPLT7gH4vgN7Xo6yZlOMrzllGbdvVxxhrwUvgI9r",
         },
+        .sdl = .{
+            .url = "https://github.com/libsdl-org/SDL/archive/refs/tags/release-3.2.14.tar.gz",
+            .hash = "N-V-__8AAHRriwPslozjEw46IksOzPlNxJRXM087krt8ynXh",
+            .version = "3.2.14",
+        },
     },
 
     .paths = .{

src/generate.zig

@@ -97,6 +97,7 @@ const Header = struct {
     const Type = struct {
         type_details: ?Details = null,
         description: Description,
+        declaration: ?[]const u8 = null,
 
         const Details = struct {
             flavour: enum { function_pointer },
@@ -300,7 +301,11 @@ fn writeTypedefs(writer: anytype, header: *const Header, declarations: *const De
         // Skip duplicate declarations (e.g. naming enums as ints in C)
         if (declarations.contains(typedef.name)) continue;
 
-        // Write the typedef
+        // Skip redundant typedefs (comes up with `SDL_Event`)
+        if (typedef.type.declaration != null and
+            std.mem.eql(u8, typedef.name, typedef.type.declaration.?)) continue;
+
+        // Write the typedef prefix
         try writer.writeAll("const ");
         try writeTypeName(writer, typedef.name);
         try writer.writeAll(" = ");
@@ -893,7 +898,7 @@ fn writeTypeName(writer: anytype, raw: []const u8) !void {
 
         // Backend prefixes
         {
-            const prefixes: []const []const u8 = &.{ "_ImplVulkanH", "_ImplVulkan" };
+            const prefixes: []const []const u8 = &.{ "_ImplVulkanH", "_ImplVulkan", "_ImplSDL3" };
             for (prefixes) |prefix| {
                 if (std.mem.startsWith(u8, name, prefix)) {
                     name = name[prefix.len..];
@@ -956,7 +961,7 @@ fn writeFunctionName(writer: anytype, raw: []const u8) !void {
 
     // Imgui prefixes
     {
-        const prefixes: []const []const u8 = &.{ "cImGui_ImplVulkan", "ImGui", "Im" };
+        const prefixes: []const []const u8 = &.{ "cImGui_ImplVulkan", "cImGui_ImplSDL3", "ImGui", "Im" };
         for (prefixes) |prefix| {
             if (std.mem.startsWith(u8, name, prefix)) {
                 name = name[prefix.len..];

src/templates/impl_sdl3_postfix.zig.template

@@ -0,0 +1,2 @@
+    };
+}

src/templates/impl_sdl3_prefix.zig.template

@@ -0,0 +1,8 @@
+const Options = struct {
+    SDLEvent: type,
+};
+
+pub fn get(options: Options) type {
+    const SDLEvent = options.SDLEvent;
+
+    return struct {