imgui working on the new sdl renderer

engine/imgui/src/imgui.zig

@@ -1,17 +1,25 @@
 const std = @import("std");
 pub const core = @import("core");
-pub const cimgui = @import("cimgui");
+pub const api = @import("cimgui");
 const rend = @import("rend");
+const Impl = @import("sgpu/backend_impl.zig").Impl;
 
 pub const Module: core.ModuleDescription = .{
     .name = "imgui",
     .enabledByDefault = false,
 };
 
+var gImgui: *Impl = undefined;
+
 pub fn start_module(comptime programSpec: anytype, args: anytype, allocator: std.mem.Allocator) !void {
     _ = allocator;
     _ = args;
     _ = programSpec;
+
+    // gImgui = try rend.createRendererObject(Impl);
+    // try gImgui.setup();
+    gImgui = try core.createObject(Impl, .{});
+    try gImgui.setup();
 }
 
 pub fn shutdown_module(allocator: std.mem.Allocator) void {

engine/imgui/src/sgpu/backend_impl.zig

@@ -1,37 +1,73 @@
-pub const ImguiImpl = struct {
+pub const Impl = struct {
     allocator: std.mem.Allocator,
-    device: *gpu.GPUDevice,
+    device: *gpu.GPUDevice = undefined,
+
+    drawData: [*c]ig.DrawData = undefined,
+
+    pub var NeonObjectTable: core.EngineObjectVTable = core.EngineObjectVTable.from(@This());
+
+    pub const Settings = struct {
+        x: u32 = 0,
+    };
 
     // renderer plugin
-    pub fn create(device: *gpu.GPUDevice, allocator: std.mem.Allocator, settings: struct {}) !*@This() {
+    pub fn create(allocator: std.mem.Allocator) !*@This() {
         const self = try allocator.create(@This());
 
         self.* = .{
             .allocator = allocator,
-            .device = device,
         };
-        _ = settings;
 
         return self;
     }
 
+    pub fn setup(self: *@This()) !void {
+        core.graphics_log("imgui startup", .{});
+        self.device = rend.context().device;
+        try rend.registerRendererObject(@This(), self);
+
+        c.Imgui_SDL3_Init(@ptrCast(platform.getInstance().window), @ptrCast(self.device));
+        try platform.getInstance().addSDLProcessFunction(processSDLEvents);
+    }
+
+    pub fn processSDLEvents(event: *sdl3.Event) void {
+        c.Imgui_SDL3_ProcessEvent(@ptrCast(event));
+    }
+
+    pub fn onPreDraw(p: *anyopaque, cmd: *gpu.GPUCommandBuffer) void {
+        const self: *@This() = @ptrCast(@alignCast(p));
+        ig.render();
+        self.drawData = ig.getDrawData();
+
+        c.Imgui_SDL3_PrepareRender(@ptrCast(self.drawData), @ptrCast(cmd));
+    }
+
+    pub fn postRender(p: *anyopaque, cmd: *gpu.GPUCommandBuffer, renderPass: *gpu.GPURenderPass) void {
+        const self: *@This() = @ptrCast(@alignCast(p));
+
+        c.ImGui_SDLGPU3_RenderDrawData(
+            @ptrCast(self.drawData),
+            @ptrCast(cmd),
+            @ptrCast(renderPass),
+        );
+    }
+
     pub fn preTick(_: *@This(), _: f64) core.EngineDataEventError!void {
-        c.ImGui_ImplGlfw_NewFrame();
-        c.cImGui_vk_NewFrame();
+        core.engine_logs("imgui pretick");
+        c.Imgui_SDL3_NewFrame();
         c.igNewFrame();
     }
 
     // renderer plugin
-    pub fn destroy(p: *anyopaque) void {
-        const self: *@This() = @ptrCast(@alignCast(p));
-
+    pub fn destroy(self: *@This()) void {
         self.allocator.destroy(self);
     }
 };
 const c = @import("cimgui").c;
-const ig = @import("cimgui").cimgui;
+const ig = @import("cimgui");
 const sdl3 = @import("sdl3");
 const gpu = sdl3.gpu;
 const rend = @import("rend");
+const platform = @import("platform");
 const std = @import("std");
 const core = @import("core");

engine/modulelist.zig

@@ -6,7 +6,7 @@ pub const list = [_][]const u8{
     "physics",
 
     "rend",
-    // "imgui",
+    "imgui",
     // to be implemented
     // "graphics",
     // "ui",

engine/platform/src/windowing.zig

@@ -75,9 +75,12 @@ pub const PlatformInstance = struct {
 
     windowDestroyed: bool = false,
 
+    processFuncs: std.ArrayListUnmanaged(*const fn (*sdl3.Event) void) = .{},
+
     pub fn deinit(self: *@This()) void {
         self.allocator.free(self.windowName);
         self.allocator.free(self.iconPath);
+        self.processFuncs.deinit(self.allocator);
         // shutdown
     }
 
@@ -105,6 +108,10 @@ pub const PlatformInstance = struct {
         return self;
     }
 
+    pub fn addSDLProcessFunction(self: *@This(), processFunc: *const fn (*sdl3.Event) void) !void {
+        try self.processFuncs.append(self.allocator, processFunc);
+    }
+
     pub fn setupWindow(self: *@This()) core.EngineDataEventError!void {
         sdl3.init(.{ .video = true, .gamepad = true }) catch return error.BadInit;
         self.window = sdl3.c.SDL_CreateWindow(self.windowName, self.windowExtent.x, self.windowExtent.y, 0).?; // resizeable
@@ -130,7 +137,8 @@ pub const PlatformInstance = struct {
     pub fn processEvents(ptr: *anyopaque, frameNumber: u64) core.EngineDataEventError!void {
         _ = frameNumber;
 
-        _ = ptr;
+        const self: *@This() = @ptrCast(@alignCast(ptr));
+
         // const self: *@This() = @ptrCast(@alignCast(ptr));
         var t1 = tracy.ZoneN(@src(), "Pumping Events");
         defer t1.End();
@@ -142,6 +150,10 @@ pub const PlatformInstance = struct {
                 inputStack.routeEvent(converted);
             }
 
+            for (self.processFuncs.items) |func| {
+                func(@ptrCast(event));
+            }
+
             switch (event.type) {
                 sdl3.events.quit => {
                     core.exitNow();

engine/rend/src/rend.zig

@@ -27,6 +27,9 @@ pub const getMeshByName = renderer.getMeshByName;
 // camera API
 pub const setActiveCamera = renderer.setActiveCamera;
 
+pub const createRendererObject = renderer.createRendererObject;
+pub const registerRendererObject = renderer.registerRendererObject;
+
 var rendAllocator: std.mem.Allocator = undefined;
 pub fn getAllocator() std.mem.Allocator {
     return rendAllocator;

engine/rend/src/sgpu/renderer.zig

@@ -30,7 +30,10 @@ pub const Renderer = struct {
 
     uploads: std.ArrayListUnmanaged(struct { ptr: *anyopaque, func: *const fn (*anyopaque, *gpu.GPUCopyPass) void }) = .{},
     uploadCleanup: std.ArrayListUnmanaged(struct { ptr: *anyopaque, func: *const fn (*anyopaque) void }) = .{},
+
+    postRenders: std.ArrayListUnmanaged(struct { ptr: *anyopaque, func: *const fn (*anyopaque, *gpu.GPUCommandBuffer, *gpu.GPURenderPass) void }) = .{},
     destroys: std.ArrayListUnmanaged(struct { ptr: *anyopaque, func: *const fn (*anyopaque) void }) = .{},
+    preDraws: std.ArrayListUnmanaged(struct { ptr: *anyopaque, func: *const fn (*anyopaque, *gpu.GPUCommandBuffer) void }) = .{},
 
     depthTexture: *gpu.GPUTexture = undefined,
 
@@ -51,12 +54,34 @@ pub const Renderer = struct {
         return self;
     }
 
-    pub fn registerRendererObject(self: *@This(), T: type) !*T {
+    // pub fn createRendererObjectArgs(self: *@This(), T: type) !*T {
+
+    // registers a pre-existing render object, does not add to destroys
+    pub fn registerRendererObject(self: *@This(), T: type, object: *anyopaque) !void {
+        if (@hasDecl(T, "onUpload")) {
+            try self.uploads.append(self.allocator, .{ .ptr = object, .func = T.onUpload });
+        }
+
+        if (@hasDecl(T, "onUploadCleanup")) {
+            try self.uploadCleanup.append(self.allocator, .{ .ptr = object, .func = T.onUploadCleanup });
+        }
+
+        if (@hasDecl(T, "postRender")) {
+            try self.postRenders.append(self.allocator, .{ .ptr = object, .func = T.postRender });
+        }
+
+        if (@hasDecl(T, "onPreDraw")) {
+            try self.preDraws.append(self.allocator, .{ .ptr = object, .func = T.onPreDraw });
+        }
+    }
+
+    pub fn createRendererObject(self: *@This(), T: type) !*T {
         const object = try T.create(self.device, self.allocator, .{});
 
-        try self.uploads.append(self.allocator, .{ .ptr = object, .func = T.onUpload });
-        try self.uploadCleanup.append(self.allocator, .{ .ptr = object, .func = T.onUploadCleanup });
+        try self.registerRendererObject(T, object);
+
         try self.destroys.append(self.allocator, .{ .ptr = object, .func = T.destroy });
+
         return object;
     }
 
@@ -94,7 +119,7 @@ pub const Renderer = struct {
         try self.createMeshPipeline();
         try self.createDepthTexture();
 
-        self.meshPool = try self.registerRendererObject(MeshPool);
+        self.meshPool = try self.createRendererObject(MeshPool);
     }
 
     pub fn discoverFormats(self: *@This()) !void {
@@ -345,6 +370,10 @@ pub const Renderer = struct {
         self.frameUploads();
         try self.uploadUniforms(cmd);
 
+        for (self.preDraws.items) |interface| {
+            interface.func(interface.ptr, cmd);
+        }
+
         var swapchainTexture: *gpu.GPUTexture = undefined;
         if (cmd.waitAndAcquireGPUSwapchainTexture(self.window, &swapchainTexture, null, null)) {
             var targetInfo: gpu.GPUColorTargetInfo = std.mem.zeroes(gpu.GPUColorTargetInfo);
@@ -391,6 +420,10 @@ pub const Renderer = struct {
                 }
             }
 
+            for (self.postRenders.items) |interface| {
+                interface.func(interface.ptr, cmd, renderpass);
+            }
+
             // renderpass.drawGPUPrimitives(3, 1, 0, 0);
 
             renderpass.endGPURenderPass();
@@ -465,6 +498,14 @@ pub fn setActiveCamera(camera: ?*rend.CameraComponent) void {
     gRenderer.activeCamera = camera;
 }
 
+pub fn createRendererObject(comptime T: type) !*T {
+    return try gRenderer.createRendererObject(T);
+}
+
+pub fn registerRendererObject(comptime T: type, object: *anyopaque) !void {
+    return try gRenderer.registerRendererObject(T, object);
+}
+
 pub const getMesh = mesh_pool.getMesh;
 pub const getMeshByName = mesh_pool.getMeshByName;
 

lib/cimgui/build.zig

@@ -12,6 +12,11 @@ pub fn build(b: *std.Build) void {
         .root_source_file = b.path("src/cimgui.zig"),
     });
 
+    mod.addIncludePath(b.path("cimgui/imgui"));
+    mod.addIncludePath(b.path("cimgui/SDL/include"));
+    mod.addIncludePath(b.path("cimplot"));
+    mod.addIncludePath(b.path("cimplot/implot"));
+
     const cimgui = b.addStaticLibrary(.{
         .name = "cimgui",
         .target = target,
@@ -34,7 +39,7 @@ pub fn build(b: *std.Build) void {
         .root = b.path("cimgui/imgui"),
         .files = &[_][]const u8{
             "cimgui.cpp",
-            // "cimgui_compat.cpp", replace with cimgui_compat_sdlgpu
+            "cimgui_compat.cpp", // replace with cimgui_compat_sdlgpu
             "imgui.cpp",
             "imgui_demo.cpp",
             "imgui_draw.cpp",

lib/cimgui/cimgui/imgui/cimgui_compat.cpp

@@ -0,0 +1,55 @@
+#include "imgui.h"
+#include "imgui_impl_sdl3.h"
+#include "imgui_impl_sdlgpu3.h"
+#include <stdio.h>          // printf, fprintf
+#include <stdlib.h>         // abort
+
+extern "C" void Imgui_SDL3_Init(SDL_Window* window, SDL_GPUDevice* gpu_device)
+{
+    ImGui::CreateContext();
+    ImGuiIO& io = ImGui::GetIO(); (void)io;
+    io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
+    io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+
+    // Setup Dear ImGui style
+    ImGui::StyleColorsDark();
+    //ImGui::StyleColorsLight();
+
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
+    // Setup Platform/Renderer backends
+    ImGui_ImplSDL3_InitForSDLGPU(window);
+    ImGui_ImplSDLGPU3_InitInfo init_info = {};
+    init_info.Device = gpu_device;
+    init_info.ColorTargetFormat = SDL_GetGPUSwapchainTextureFormat(gpu_device, window);
+    init_info.MSAASamples = SDL_GPU_SAMPLECOUNT_1;
+    ImGui_ImplSDLGPU3_Init(&init_info);}
+
+extern "C" void Imgui_SDL3_ProcessEvent(SDL_Event* Event)
+{
+    ImGui_ImplSDL3_ProcessEvent(Event);
+}
+
+extern "C" void Imgui_SDL3_NewFrame()
+{
+    ImGui_ImplSDLGPU3_NewFrame();
+    ImGui_ImplSDL3_NewFrame();
+}
+
+extern "C" void ImGui_SDLGPU3_RenderDrawData(ImDrawData* draw_data, SDL_GPUCommandBuffer* command_buffer, SDL_GPURenderPass* render_pass, SDL_GPUGraphicsPipeline* pipeline)
+{
+    ImGui_ImplSDLGPU3_RenderDrawData(draw_data, command_buffer, render_pass, nullptr);
+}
+
+extern "C" void Imgui_SDL3_PrepareRender(ImDrawData* draw_data, SDL_GPUCommandBuffer* command_buffer)
+{
+    Imgui_ImplSDLGPU3_PrepareDrawData(draw_data, command_buffer);
+}

lib/cimgui/cimgui/imgui/cimgui_compat.h

@@ -0,0 +1,16 @@
+#pragma once
+
+#include <SDL3/SDL.h>
+
+#if __cplusplus
+extern "C"{
+#endif
+void Imgui_SDL3_Init(SDL_Window* window, SDL_GPUDevice* gpu_device);
+void Imgui_SDL3_ProcessEvent(SDL_Event* Event);
+void Imgui_SDL3_NewFrame();
+void ImGui_SDLGPU3_RenderDrawData(ImDrawData* draw_data, SDL_GPUCommandBuffer* command_buffer, SDL_GPURenderPass* render_pass);
+void Imgui_SDL3_PrepareRender(ImDrawData* draw_data, SDL_GPUCommandBuffer* command_buffer);
+
+#if __cplusplus
+}
+#endif

lib/cimgui/cimplot/cimplot.h

@@ -28,11 +28,11 @@ typedef struct ImVector_ImS64 {int Size;int Capacity;ImS64* Data;} ImVector_ImS6
 
 typedef struct ImVector_ImS8 {int Size;int Capacity;ImS8* Data;} ImVector_ImS8;
 
-typedef struct ImVector_ImU16 {int Size;int Capacity;ImU16* Data;} ImVector_ImU16;
+// typedef struct ImVector_ImU16 {int Size;int Capacity;ImU16* Data;} ImVector_ImU16;
 
 typedef struct ImVector_ImU64 {int Size;int Capacity;ImU64* Data;} ImVector_ImU64;
 
-typedef struct ImVector_ImU8 {int Size;int Capacity;ImU8* Data;} ImVector_ImU8;
+// typedef struct ImVector_ImU8 {int Size;int Capacity;ImU8* Data;} ImVector_ImU8;
 
 struct ImPlotContext;
 typedef int ImAxis;

projects/sampleGame/main.zig

@@ -118,6 +118,10 @@ pub fn tick(self: *@This(), dt: f64) void {
         scene.getPosRot().position = scene.getPosRot().position.add(vector.fmul(self.cameraSpeed * fdt));
         // core.engine_log(" camera position >> {any}", .{scene.getPosRot().position});
     }
+
+    var show: bool = true;
+
+    ig.showDemoWindow(&show);
 }
 
 pub fn deinit(self: *@This()) void {
@@ -138,5 +142,6 @@ const std = @import("std");
 const backlog = @import("Backlog");
 const assets = backlog.assets;
 const core = backlog.core;
+const ig = backlog.imgui.api;
 const rend = backlog.rend;
 const script = core.script;