player: x11 bitmap window

Player/Display/display.h

@@ -0,0 +1,2 @@
+
+extern int plr_display_x11_main(int argc, char *argv[]);

Player/Display/x11.c

@@ -0,0 +1,120 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <X11/X.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include "display.h"
+
+bool quited = false;
+
+#define WIDTH  640
+#define HEIGHT 480
+
+// TODO: correct error handling.
+extern int plr_display_x11_main(int argc, char *argv[])
+{
+    Display *display = XOpenDisplay(NULL);
+    if (NULL == display) {
+        fprintf(stderr, "Failed to initialize display");
+        return EXIT_FAILURE;
+    }
+
+    Window root = DefaultRootWindow(display);
+    if (None == root) {
+        fprintf(stderr, "No root window found");
+        XCloseDisplay(display);
+        return EXIT_FAILURE;
+    }
+
+    int screen = DefaultScreen(display);
+    Visual *visual = DefaultVisual(display, screen);
+    int depth = DefaultDepth(display, screen);
+
+    Window window = XCreateSimpleWindow(display, root, 0, 0, WIDTH, HEIGHT, 0, 0, 0xffffffff);
+    if (None == window) {
+        fprintf(stderr, "Failed to create window");
+        XCloseDisplay(display);
+        return EXIT_FAILURE;
+    }
+
+    XSizeHints *hints = XAllocSizeHints();
+    if (hints == NULL) return EXIT_FAILURE;
+
+    // Pinning min and max to the same values disables resizing
+    hints->flags = PMinSize | PMaxSize;
+    hints->min_width = hints->max_width = WIDTH;
+    hints->min_height = hints->max_height = HEIGHT;
+
+    XSetWMNormalHints(display, window, hints);
+    XFree(hints);
+
+    XSelectInput(display, window, ExposureMask | KeyPressMask);
+    XMapWindow(display, window);
+
+    GC gc = XCreateGC(display, window, 0, NULL);
+
+    Atom wm_delete_window = XInternAtom(display, "WM_DELETE_WINDOW", False);
+    XSetWMProtocols(display, window, & wm_delete_window, 1);
+
+    // TODO: can't be not true
+    int bytes_per_pixel = 4;
+    char *pixel_buffer = (char *)malloc(WIDTH * HEIGHT * bytes_per_pixel);
+
+    XImage *ximage = XCreateImage(
+        display, visual, depth, ZPixmap, 0, 
+        pixel_buffer, WIDTH, HEIGHT, 32, 0
+    );
+
+    if (!ximage) {
+        fprintf(stderr, "Failed to create XImage\n");
+        free(pixel_buffer);
+        XCloseDisplay(display);
+        return EXIT_FAILURE;
+    }
+
+    int frame = 0;
+
+    XEvent event;
+    while (!quited) {
+        XNextEvent(display, &event);
+
+        switch(event.type) {
+        case ClientMessage:
+            if(event.xclient.data.l[0] == wm_delete_window) {
+                XDestroyWindow(display, window);
+                quited = true;
+            }
+            break;
+        case Expose:
+            frame += 2;
+            // Fill buffer with a simple color gradient
+            for (int y = 0; y < HEIGHT; y++) {
+                for (int x = 0; x < WIDTH; x++) {
+                    int pixel_index = (y * WIDTH + x) * bytes_per_pixel;
+                    
+                    // Assuming standard Little-Endian 32-bit BGRA format
+                    pixel_buffer[pixel_index + 0] = (x + frame) % 256;         // Blue
+                    pixel_buffer[pixel_index + 1] = (y + frame) % 256;         // Green
+                    pixel_buffer[pixel_index + 2] = (x + y - frame) % 256;     // Red
+                    pixel_buffer[pixel_index + 3] = 0;                         // Alpha/Padding
+                }
+            }
+            // Draw the complete image onto the window when exposed
+            XPutImage(
+                display, 
+                window,      // Target drawable
+                gc,          // Graphics Context
+                ximage,      // Source XImage
+                0, 0,        // Source coordinates (x, y)
+                0, 0,        // Destination coordinates (x, y)
+                WIDTH, HEIGHT// Dimensions to copy
+            );
+            break;
+        }
+    }
+
+    XCloseDisplay(display);
+
+    return 0;
+}