Actually show a window

2 files changed, 116 insertions, 3 deletions

diff --git a/main.c b/main.c
index 4662ae3..8142abf 100644
--- a/main.c
+++ b/main.c
@@ -1,8 +1,35 @@
 #include <stdio.h>
+#include "window.h"
 
 int
 main ()
 {
+    ws_t *ws = ws_open();
+    window_t *window;
+    pixman_image_t *image;
+    pixman_color_t color = { 0xffff, 0xabcd, 0x7777, 0x7777 };
+
+    if (!ws)
+    {
+	printf ("could not open display\n");
+	return 0;
+    }
+
+    window = ws_create_window (ws, 10, 10, 200, 200);
+
+    ws_window_show (window);
+
+    image = pixman_image_create_solid_fill (&color);
+
+    while (1)
+    {
+	ws_window_copy_from_image (window, image, 0, 0, 0, 0, 200, 200);
+
+	ws_window_finish (&window, 1);
+    }
+
     printf ("Hello world\n");
+    while (1)
+	;
     return 0;
 }
diff --git a/window.c b/window.c
index f130204..a189ac5 100644
--- a/window.c
+++ b/window.c
@@ -1,6 +1,7 @@
 #include <stdlib.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
+#include <assert.h>
 #include "window.h"
 
 struct ws_t
@@ -10,6 +11,7 @@ struct ws_t
     pixman_format_code_t	format;
     pixman_bool_t		composited;
     pixman_bool_t		has_alpha;
+    int				byte_order;
 };
 
 struct window_t
@@ -42,6 +44,43 @@ popcount (uint32_t v)
     return n;
 }
 
+/* A mask consisting of N bits set to 1. */
+#define MASK(N) ((1UL << (N))-1)
+
+static void
+format_to_masks (pixman_format_code_t format,
+		 uint32_t *alpha,
+		 uint32_t *red,
+		 uint32_t *green,
+		 uint32_t *blue)
+{
+    int a, r, g, b;
+
+    a = PIXMAN_FORMAT_A (format);
+    r = PIXMAN_FORMAT_R (format);
+    g = PIXMAN_FORMAT_G (format);
+    b = PIXMAN_FORMAT_B (format);
+
+    if (PIXMAN_FORMAT_TYPE (format) == PIXMAN_TYPE_ARGB)
+    {
+	*alpha = MASK (a) << (r + g + b);
+	*red   = MASK (r) << (g + b);
+	*green = MASK (g) << (g);
+	*blue  = MASK (b);
+    }
+    else if (PIXMAN_FORMAT_TYPE (format) == PIXMAN_TYPE_ABGR)
+    {
+	*alpha = MASK (a) << (b + g + r);
+	*red   = MASK (r) << (g + r);
+	*green = MASK (g) << (r);
+	*blue  = MASK (b);
+    }
+    else
+    {
+	assert (0);
+    }
+}
+
 static pixman_bool_t
 visual_to_format (Visual *visual, int depth, pixman_format_code_t *format_o)
 {
@@ -90,6 +129,7 @@ ws_open (void)
     ws_t *ws;
     Display *display;
     int depth;
+    int x;
 
     if (!(display = XOpenDisplay (NULL)))
 	return NULL;
@@ -135,6 +175,13 @@ ws_open (void)
     if (!visual_to_format (ws->visual, depth, &ws->format))
 	return NULL;
 
+    x = 1;
+
+    if (*(char *)&x == 1)
+	ws->byte_order = LSBFirst;
+    else
+	ws->byte_order = MSBFirst;
+
     return ws;
 }
 
@@ -292,7 +339,7 @@ ws_window_copy_from_image (window_t       *window,
 {
     /* copy from image to backing */
     pixman_image_composite32 (PIXMAN_OP_SRC,
-			      window->backing_store, NULL, image,
+			      image, NULL, window->backing_store,
 			      win_x, win_y, 0, 0, image_x, image_y,
 			      width, height);
 }
@@ -309,7 +356,7 @@ ws_window_copy_to_image (window_t       *window,
 {
     /* copy from backing to image */
     pixman_image_composite32 (PIXMAN_OP_SRC,
-			      image, NULL, window->backing_store,
+			      window->backing_store, NULL, image,
 			      image_x, image_y, 0, 0, win_x, win_y,
 			      width, height);
 }
@@ -318,5 +365,44 @@ void
 ws_window_finish (window_t  **windows,
 		  int	      n_windows)
 {
-    
+    int i;
+
+    for (i = 0; i < n_windows; ++i)
+    {
+	window_t *window = windows[i];
+	pixman_format_code_t format = window->ws->format;
+	Display *dpy = window->ws->display;
+	uint32_t a, r, g, b;
+	XImage image;
+	XGCValues values;
+	GC gc;
+
+	format_to_masks (format, &a, &r, &g, &b);
+
+	image.width = get_width (window);
+	image.height = get_height (window);
+	image.xoffset = 0;
+	image.format = ZPixmap;
+	image.data = (char *)pixman_image_get_data (window->backing_store);
+	image.byte_order = window->ws->byte_order;
+	image.bitmap_unit = 32;
+	image.bitmap_bit_order = window->ws->byte_order;
+	image.bitmap_pad = 32;
+	image.depth = PIXMAN_FORMAT_DEPTH (format);
+	image.bytes_per_line = pixman_image_get_stride (window->backing_store);
+	image.bits_per_pixel = PIXMAN_FORMAT_BPP (format);
+	image.red_mask = r;
+	image.green_mask = g;
+	image.blue_mask = b;
+
+	XInitImage (&image);
+
+	gc = XCreateGC (dpy, window->xid, 0, &values);
+
+	XPutImage (dpy, window->xid, gc, &image,
+		   0, 0, 0, 0, image.width, image.height);
+
+	XFreeGC (dpy, gc);
+	XFlush (dpy);
+    }
 }