leftovers

2026-05-12 11:53:02 +02:00
parent e181656f04
commit 275ca96e74
12 changed files with 1316 additions and 1 deletions
@@ -0,0 +1,212 @@
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <immintrin.h>
+#include <stdint.h>
+#include <math.h>
+#include <thread>
+#include <vector>
+
+#pragma comment(lib, "user32.lib")
+#pragma comment(lib, "gdi32.lib")
+
+#define WIDTH  1280
+#define HEIGHT 800
+#define MAX_ITER 1000
+
+static uint32_t framebuffer[WIDTH * HEIGHT];
+
+static double centerX = -0.5;
+static double centerY = 0.0;
+static double scale = 3.0 / WIDTH;
+
+static int dragging = 0;
+static int lastX, lastY;
+
+static int numThreads = std::thread::hardware_concurrency();
+
+static void render_tile(int yStart, int yEnd)
+{
+    __m256d two = _mm256_set1_pd(2.0);
+    __m256d four = _mm256_set1_pd(4.0);
+
+    for (int y = yStart; y < yEnd; y++)
+    {
+        double ci_scalar = centerY + (y - HEIGHT / 2.0) * scale;
+        __m256d ci = _mm256_set1_pd(ci_scalar);
+
+        for (int x = 0; x < WIDTH; x += 4)
+        {
+            __m256d cr = _mm256_set_pd(
+                centerX + (x + 3 - WIDTH / 2.0) * scale,
+                centerX + (x + 2 - WIDTH / 2.0) * scale,
+                centerX + (x + 1 - WIDTH / 2.0) * scale,
+                centerX + (x + 0 - WIDTH / 2.0) * scale
+            );
+
+            __m256d zr = _mm256_setzero_pd();
+            __m256d zi = _mm256_setzero_pd();
+
+            int iter[4] = { 0,0,0,0 };
+
+            for (int i = 0; i < MAX_ITER; i++)
+            {
+                __m256d zr2 = _mm256_mul_pd(zr, zr);
+                __m256d zi2 = _mm256_mul_pd(zi, zi);
+                __m256d mag = _mm256_add_pd(zr2, zi2);
+
+                __m256d mask = _mm256_cmp_pd(mag, four, _CMP_LT_OS);
+                if (_mm256_movemask_pd(mask) == 0)
+                    break;
+
+                __m256d zrzi = _mm256_mul_pd(zr, zi);
+
+                zi = _mm256_add_pd(_mm256_mul_pd(two, zrzi), ci);
+                zr = _mm256_add_pd(_mm256_sub_pd(zr2, zi2), cr);
+
+                for (int k = 0; k < 4; k++)
+                    if (iter[k] < MAX_ITER)
+                        iter[k]++;
+            }
+
+            for (int k = 0; k < 4; k++)
+            {
+                double smooth = iter[k];
+                if (iter[k] < MAX_ITER)
+                {
+                    double zr_s = ((double*)&zr)[k];
+                    double zi_s = ((double*)&zi)[k];
+                    double mag = sqrt(zr_s * zr_s + zi_s * zi_s);
+                    smooth = iter[k] + 1 - log2(log2(mag));
+                }
+
+                uint8_t c = (uint8_t)(255.0 * smooth / MAX_ITER);
+                framebuffer[y * WIDTH + x + k] =
+                    (c << 16) | (c << 8) | c;
+            }
+        }
+    }
+}
+
+static void render_mandelbrot()
+{
+    std::vector<std::thread> threads;
+
+    int tile = HEIGHT / numThreads;
+
+    for (int i = 0; i < numThreads; i++)
+    {
+        int yStart = i * tile;
+        int yEnd = (i == numThreads - 1) ? HEIGHT : yStart + tile;
+        threads.emplace_back(render_tile, yStart, yEnd);
+    }
+
+    for (auto& t : threads)
+        t.join();
+}
+
+LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
+{
+    switch (msg)
+    {
+    case WM_MOUSEWHEEL:
+    {
+        int delta = GET_WHEEL_DELTA_WPARAM(wParam);
+        scale *= (delta > 0) ? 0.8 : 1.25;
+        render_mandelbrot();
+        InvalidateRect(hwnd, NULL, FALSE);
+        break;
+    }
+
+    case WM_LBUTTONDOWN:
+        dragging = 1;
+        lastX = LOWORD(lParam);
+        lastY = HIWORD(lParam);
+        break;
+
+    case WM_MOUSEMOVE:
+        if (dragging)
+        {
+            int x = LOWORD(lParam);
+            int y = HIWORD(lParam);
+
+            centerX -= (x - lastX) * scale;
+            centerY -= (y - lastY) * scale;
+
+            lastX = x;
+            lastY = y;
+
+            render_mandelbrot();
+            InvalidateRect(hwnd, NULL, FALSE);
+        }
+        break;
+
+    case WM_LBUTTONUP:
+        dragging = 0;
+        break;
+
+    case WM_PAINT:
+    {
+        PAINTSTRUCT ps;
+        HDC hdc = BeginPaint(hwnd, &ps);
+
+        BITMAPINFO bmi = {};
+        bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
+        bmi.bmiHeader.biWidth = WIDTH;
+        bmi.bmiHeader.biHeight = -HEIGHT;
+        bmi.bmiHeader.biPlanes = 1;
+        bmi.bmiHeader.biBitCount = 32;
+        bmi.bmiHeader.biCompression = BI_RGB;
+
+        StretchDIBits(hdc,
+            0, 0, WIDTH, HEIGHT,
+            0, 0, WIDTH, HEIGHT,
+            framebuffer,
+            &bmi,
+            DIB_RGB_COLORS,
+            SRCCOPY);
+
+        EndPaint(hwnd, &ps);
+        break;
+    }
+
+    case WM_DESTROY:
+        PostQuitMessage(0);
+        break;
+
+    default:
+        return DefWindowProc(hwnd, msg, wParam, lParam);
+    }
+    return 0;
+}
+
+int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE, LPSTR, int nCmdShow)
+{
+    render_mandelbrot();
+
+    WNDCLASS wc = {};
+    wc.lpfnWndProc = WndProc;
+    wc.hInstance = hInstance;
+    wc.lpszClassName = "MandelbrotSIMD";
+
+    RegisterClass(&wc);
+
+    HWND hwnd = CreateWindowEx(
+        0,
+        "MandelbrotSIMD",
+        "Mandelbrot Explorer (SIMD + Threads)",
+        WS_OVERLAPPEDWINDOW,
+        CW_USEDEFAULT, CW_USEDEFAULT,
+        WIDTH, HEIGHT,
+        NULL, NULL, hInstance, NULL);
+
+    ShowWindow(hwnd, nCmdShow);
+
+    MSG msg;
+    while (GetMessage(&msg, NULL, 0, 0))
+    {
+        TranslateMessage(&msg);
+        DispatchMessage(&msg);
+    }
+
+    return 0;
+}