1 files changed, 118 insertions, 0 deletions
diff --git a/twin_pixmap.c b/twin_pixmap.c
new file mode 100644
index 0000000..3610e01
--- /dev/null
+++ b/twin_pixmap.c
@@ -0,0 +1,118 @@
+/*
+ * $Id$
+ *
+ * Copyright © 2004 Keith Packard
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation, and that the name of Keith Packard not be used in
+ * advertising or publicity pertaining to distribution of the software without
+ * specific, written prior permission.  Keith Packard makes no
+ * representations about the suitability of this software for any purpose.  It
+ * is provided "as is" without express or implied warranty.
+ *
+ * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "twinint.h"
+
+twin_pixmap_t *
+twin_pixmap_create (twin_format_t format, int width, int height)
+{
+    int	stride = twin_bytes_per_pixel (format) * width;
+    int	size = sizeof (twin_pixmap_t) + stride * height;
+    twin_pixmap_t   *pixmap = malloc (size);
+    if (!pixmap)
+	return 0;
+    pixmap->screen = 0;
+    pixmap->higher = 0;
+    pixmap->x = pixmap->y = 0;
+    pixmap->format = format;
+    pixmap->width = width;
+    pixmap->height = height;
+    pixmap->stride = stride;
+    pixmap->p.v = pixmap + 1;
+    return pixmap;
+}
+
+void
+twin_pixmap_destroy (twin_pixmap_t *pixmap)
+{
+    if (pixmap->screen)
+	twin_pixmap_hide (pixmap);
+    free (pixmap);
+}
+
+void
+twin_pixmap_show (twin_pixmap_t	*pixmap, 
+		  twin_screen_t	*screen,
+		  twin_pixmap_t	*lower)
+{
+    twin_pixmap_t   **higherp;
+    if (pixmap->screen)
+	twin_pixmap_hide (pixmap);
+    pixmap->screen = screen;
+    if (lower)
+	higherp = &lower->higher;
+    else
+	higherp = &screen->bottom;
+    pixmap->higher = *higherp;
+    *higherp = pixmap;
+    twin_pixmap_damage (pixmap, 0, 0, pixmap->width, pixmap->height);
+}
+
+void
+twin_pixmap_hide (twin_pixmap_t *pixmap)
+{
+    twin_screen_t   *screen = pixmap->screen;
+    twin_pixmap_t   **higherp;
+
+    if (!screen)
+	return;
+    twin_pixmap_damage (pixmap, 0, 0, pixmap->width, pixmap->height);
+    for (higherp = &screen->bottom; *higherp != pixmap; higherp = &(*higherp)->higher)
+	;
+    *higherp = pixmap->higher;
+    pixmap->screen = 0;
+    pixmap->higher = 0;
+}
+
+twin_pointer_t
+twin_pixmap_pointer (twin_pixmap_t *pixmap, int x, int y)
+{
+    twin_pointer_t  p;
+
+    p.b = (pixmap->p.b + 
+	   y * pixmap->stride + 
+	   x * twin_bytes_per_pixel(pixmap->format));
+    return p;
+}
+
+void
+twin_pixmap_damage (twin_pixmap_t *pixmap,
+		    int x1, int y1, int x2, int y2)
+{
+    if (pixmap->screen)
+	twin_screen_damage (pixmap->screen,
+			    x1 + pixmap->x,
+			    y1 + pixmap->y,
+			    x2 + pixmap->x,
+			    y2 + pixmap->y);
+}
+
+void
+twin_pixmap_move (twin_pixmap_t *pixmap, int x, int y)
+{
+    twin_pixmap_damage (pixmap, 0, 0, pixmap->width, pixmap->height);
+    pixmap->x = x;
+    pixmap->y = y;
+    twin_pixmap_damage (pixmap, 0, 0, pixmap->width, pixmap->height);
+}