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authorbhgv <bhgv.empire@gmail.com>2018-03-01 16:54:45 +0200
committerbhgv <bhgv.empire@gmail.com>2018-03-01 16:54:45 +0200
commitb786f20bbab5a59046aa78a2c6c2a11536497202 (patch)
tree0851ecdec889eb9b7ba3751cc04d4f0b474e4a9e /libdraw/writecolmap.c
inferno-os tree was separated from the inferno-os-android (separated from the Android driver)
Diffstat (limited to 'libdraw/writecolmap.c')
-rw-r--r--libdraw/writecolmap.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/libdraw/writecolmap.c b/libdraw/writecolmap.c
new file mode 100644
index 0000000..6bbc7fe
--- /dev/null
+++ b/libdraw/writecolmap.c
@@ -0,0 +1,37 @@
+#include "lib9.h"
+#include "draw.h"
+#include "kernel.h"
+
+/*
+ * This code (and the devdraw interface) will have to change
+ * if we ever get bitmaps with ldepth > 3, because the
+ * colormap will have to be written in chunks
+ */
+
+void
+writecolmap(Display *d, RGB *m)
+{
+ int i, n, fd;
+ char buf[64], *t;
+ ulong r, g, b;
+
+ sprint(buf, "/dev/draw/%d/colormap", d->dirno);
+ fd = open(buf, OWRITE);
+ if(fd < 0)
+ drawerror(d, "wrcolmap: open colormap failed");
+ t = malloc(8192);
+ if(t == nil)
+ return;
+ n = 0;
+ for(i = 0; i < 256; i++) {
+ r = m[i].red>>24;
+ g = m[i].green>>24;
+ b = m[i].blue>>24;
+ n += sprint(t+n, "%d %lud %lud %lud\n", 255-i, r, g, b);
+ }
+ i = libwrite(fd, t, n);
+ free(t);
+ close(fd);
+ if(i != n)
+ drawerror(d, "wrcolmap: bad write");
+}