Engine.cpp

#include "imgui.h"
#include "imgui_impl_opengl3.h"
#include "imgui_impl_win32.h"
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#include <tchar.h>
#include <UI.h>
#include <Renderer.h>

__declspec(dllexport) DWORD NvOptimusEnablement = 1;
__declspec(dllexport) int AmdPowerXpressRequestHighPerformance = 1;

// Data stored per platform window
struct WGL_WindowData { HDC hDC; };

// Data
static HGLRC            g_hRC;
static WGL_WindowData   g_MainWindow;
static int              g_Width;
static int              g_Height;

bool CreateDeviceWGL(HWND hWnd, WGL_WindowData* data);
void CleanupDeviceWGL(HWND hWnd, WGL_WindowData* data);
void ResetDeviceWGL();
LRESULT WINAPI WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);

static void Hook_Renderer_CreateWindow(ImGuiViewport* viewport)
{
    assert(viewport->RendererUserData == NULL);

    WGL_WindowData* data = IM_NEW(WGL_WindowData);
    CreateDeviceWGL((HWND)viewport->PlatformHandle, data);
    viewport->RendererUserData = data;
}

static void Hook_Renderer_DestroyWindow(ImGuiViewport* viewport)
{
    if (viewport->RendererUserData != NULL)
    {
        WGL_WindowData* data = (WGL_WindowData*)viewport->RendererUserData;
        CleanupDeviceWGL((HWND)viewport->PlatformHandle, data);
        IM_DELETE(data);
        viewport->RendererUserData = NULL;
    }
}

static void Hook_Platform_RenderWindow(ImGuiViewport* viewport, void*)
{
    // Activate the platform window DC in the OpenGL rendering context
    if (WGL_WindowData* data = (WGL_WindowData*)viewport->RendererUserData)
        wglMakeCurrent(data->hDC, g_hRC);
}

static void Hook_Renderer_SwapBuffers(ImGuiViewport* viewport, void*)
{
    if (WGL_WindowData* data = (WGL_WindowData*)viewport->RendererUserData)
        ::SwapBuffers(data->hDC);
}

GLuint CreateTexture(cl_float* rgbData, int width, int height) {
    GLuint texture;
    glGenTextures(1, &texture);  // Generate a texture ID
    glBindTexture(GL_TEXTURE_2D, texture);  // Bind the texture

    // Specify the texture image data (consider using GL_UNSIGNED_BYTE if needed)
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_FLOAT, rgbData);

    // Set texture parameters for wrapping and filtering
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);  // Change to GL_CLAMP
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);  // Change to GL_CLAMP
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

    return texture;  // Return the texture ID
}


int main(int, char**)
{
    // Create application window
    //ImGui_ImplWin32_EnableDpiAwareness();
    WNDCLASSEXW wc = { sizeof(wc), CS_OWNDC, WndProc, 0L, 0L, GetModuleHandle(nullptr), nullptr, nullptr, nullptr, nullptr, L"ImGui Example", nullptr };
    ::RegisterClassExW(&wc);
    HWND hwnd = ::CreateWindowW(wc.lpszClassName, L"Engine", WS_OVERLAPPEDWINDOW, 0, 0, 1600, 1000, nullptr, nullptr, wc.hInstance, nullptr);

    // Initialize OpenGL
    if (!CreateDeviceWGL(hwnd, &g_MainWindow))
    {
        CleanupDeviceWGL(hwnd, &g_MainWindow);
        ::DestroyWindow(hwnd);
        ::UnregisterClassW(wc.lpszClassName, wc.hInstance);
        return 1;
    }
    wglMakeCurrent(g_MainWindow.hDC, g_hRC);

    // Show the window
    ::ShowWindow(hwnd, SW_SHOWDEFAULT);
    ::UpdateWindow(hwnd);

    // Setup Dear ImGui context
    IMGUI_CHECKVERSION();
    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::StyleColorsClassic();

    ImGuiStyle& style = ImGui::GetStyle();
    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
    {
        style.WindowRounding = 0.0f;
        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
    }

    ImGui_ImplWin32_InitForOpenGL(hwnd);
    ImGui_ImplOpenGL3_Init();

    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
    {
        ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
        IM_ASSERT(platform_io.Renderer_CreateWindow == NULL);
        IM_ASSERT(platform_io.Renderer_DestroyWindow == NULL);
        IM_ASSERT(platform_io.Renderer_SwapBuffers == NULL);
        IM_ASSERT(platform_io.Platform_RenderWindow == NULL);
        platform_io.Renderer_CreateWindow = Hook_Renderer_CreateWindow;
        platform_io.Renderer_DestroyWindow = Hook_Renderer_DestroyWindow;
        platform_io.Renderer_SwapBuffers = Hook_Renderer_SwapBuffers;
        platform_io.Platform_RenderWindow = Hook_Platform_RenderWindow;
    }

    bool show_demo_window = true;
    bool show_another_window = false;
    ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);

    // init Renderer
    vector<char*> files;

    //files.push_back("Renderer/kernel_float3.cl");

    files.push_back("Renderer/kernel.cl");

    OpenClinit(files);

    cl_float* output;

    struct Camera camera;

    camera.width = 900;
    camera.aspect_ratio = 16.0/9.0;
    camera.fov = 90;
    camera.position.x = 0;
    camera.position.y = 0;
    camera.position.z = 1;
    camera.look.x = 0;
    camera.look.y = 0;
    camera.look.z = 0;
    camera.vup.x = 0;
    camera.vup.y = 1;
    camera.vup.z = 0;
    camera.mode = 0;
    camera.frames = 0;

    struct Shader shader;
    struct Palette palette;
    struct Scene scene;

    GLuint texture;

    int objects = 3;

    scene.objects = objects;
    scene.samples = 100;
    scene.depth = 50;

    struct Object scened[MAX_OBJECTS];

    memset(scened,0,sizeof(struct Object)*MAX_OBJECTS);

    scened[0].type = 1;
    cl_float3 pos = {0.0,0.0,-1.0};
    scened[0].position = pos;
    scened[0].radius = 0.5;
    cl_float3 color = {0.7,0.1,0.3};
    scened[0].color = color;
    scened[0].mat = 1;

    scened[1].type = 1;
    pos = {0.0,-100.5,-1.0};
    scened[1].position = pos;
    scened[1].radius = 100.0;
    color = {0.4,0.3,0.1};
    scened[1].color = color;
    scened[1].mat = 1;

    scened[2].type = 1;
    pos = {1.0,0.0,-1.0};
    scened[2].position = pos;
    scened[2].radius = 0.5;
    color = {0.9,0.2,0.1};
    scened[2].color = color;
    scened[2].mat = 1;

    // Main loop
    bool done = false;
    while (!done)
    {
        MSG msg;
        while (::PeekMessage(&msg, nullptr, 0U, 0U, PM_REMOVE))
        {
            ::TranslateMessage(&msg);
            ::DispatchMessage(&msg);
            if (msg.message == WM_QUIT)
                done = true;
        }
        if (done)
            break;
        if (::IsIconic(hwnd))
        {
            ::Sleep(10);
            continue;
        }

        // Start the Dear ImGui frame
        ImGui_ImplOpenGL3_NewFrame();
        ImGui_ImplWin32_NewFrame();
        ImGui::NewFrame();

        UI(texture,&camera,&shader,&palette,&scene,scened);
        UpdateCamera(&camera);
        output = RunKernal(camera,shader,palette,scene,scened);
        texture = CreateTexture(output,camera.width,camera.height);

        delete [] output;

        camera.frames += 1;

        if (camera.frames > INT_MAX - 100) camera.frames = 0;

        // Rendering
        ImGui::Render();
        glViewport(0, 0, g_Width, g_Height);
        glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
        glClear(GL_COLOR_BUFFER_BIT);
        ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());

        // Update and Render additional Platform Windows
        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
        {
            ImGui::UpdatePlatformWindows();
            ImGui::RenderPlatformWindowsDefault();

            // Restore the OpenGL rendering context to the main window DC, since platform windows might have changed it.
            wglMakeCurrent(g_MainWindow.hDC, g_hRC);
        }

        // Present
        ::SwapBuffers(g_MainWindow.hDC);
    }

    free((char*)kernel_s);

    ImGui_ImplOpenGL3_Shutdown();
    ImGui_ImplWin32_Shutdown();
    ImGui::DestroyContext();

    CleanupDeviceWGL(hwnd, &g_MainWindow);
    wglDeleteContext(g_hRC);
    ::DestroyWindow(hwnd);
    ::UnregisterClassW(wc.lpszClassName, wc.hInstance);

    return 0;
}

// Helper functions
bool CreateDeviceWGL(HWND hWnd, WGL_WindowData* data)
{
    HDC hDc = ::GetDC(hWnd);
    PIXELFORMATDESCRIPTOR pfd = { 0 };
    pfd.nSize = sizeof(pfd);
    pfd.nVersion = 1;
    pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;
    pfd.iPixelType = PFD_TYPE_RGBA;
    pfd.cColorBits = 32;

    const int pf = ::ChoosePixelFormat(hDc, &pfd);
    if (pf == 0)
        return false;
    if (::SetPixelFormat(hDc, pf, &pfd) == FALSE)
        return false;
    ::ReleaseDC(hWnd, hDc);

    data->hDC = ::GetDC(hWnd);
    if (!g_hRC)
        g_hRC = wglCreateContext(data->hDC);
    return true;
}

void CleanupDeviceWGL(HWND hWnd, WGL_WindowData* data)
{
    wglMakeCurrent(nullptr, nullptr);
    ::ReleaseDC(hWnd, data->hDC);
}

extern IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);

LRESULT WINAPI WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    if (ImGui_ImplWin32_WndProcHandler(hWnd, msg, wParam, lParam))
        return true;

    switch (msg)
    {
    case WM_SIZE:
        if (wParam != SIZE_MINIMIZED)
        {
            g_Width = LOWORD(lParam);
            g_Height = HIWORD(lParam);
        }
        return 0;
    case WM_SYSCOMMAND:
        if ((wParam & 0xfff0) == SC_KEYMENU) // Disable ALT application menu
            return 0;
        break;
    case WM_DESTROY:
        ::PostQuitMessage(0);
        return 0;
    }
    return ::DefWindowProcW(hWnd, msg, wParam, lParam);
}