Make scaler output truly pluggable, add an 8-bit greyscale output to

pluginlib for use with greylib, and add source for a test scaled bmp
viewer using greylib.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19593 a1c6a512-1295-4272-9138-f99709370657

2 files changed, 20 insertions, 0 deletions

diff --git a/apps/plugins/lib/grey.h b/apps/plugins/lib/grey.h
index 8f8de9db99..8c9d40ab8d 100644
--- a/apps/plugins/lib/grey.h
+++ b/apps/plugins/lib/grey.h
@@ -106,6 +106,7 @@ void grey_ub_gray_bitmap_part(const unsigned char *src, int src_x, int src_y,
                               int stride, int x, int y, int width, int height);
 void grey_ub_gray_bitmap(const unsigned char *src, int x, int y, int width,
                          int height);
+extern const struct custom_format format_grey;
 
 /* Text */
 void grey_putsxyofs(int x, int y, int ofs, const unsigned char *str);
diff --git a/apps/plugins/lib/grey_draw.c b/apps/plugins/lib/grey_draw.c
index e9812b6784..51d340dd7f 100644
--- a/apps/plugins/lib/grey_draw.c
+++ b/apps/plugins/lib/grey_draw.c
@@ -669,3 +669,22 @@ void grey_ub_gray_bitmap(const unsigned char *src, int x, int y, int width,
 {
     grey_ub_gray_bitmap_part(src, 0, 0, width, x, y, width, height);
 }
+
+static void output_row_grey(uint32_t row, void * row_in, struct scaler_context *ctx)
+{
+    int col;
+    uint32_t *qp = (uint32_t*)row_in;
+    uint8_t *dest = (uint8_t*)ctx->bm->data + ctx->bm->width * row;
+    for (col = 0; col < ctx->bm->width; col++)
+        *dest++ = ((*qp++) + ctx->round) * (uint64_t)ctx->divisor >> 32;
+}
+
+static unsigned int get_size_grey(struct bitmap *bm)
+{
+    return bm->width * bm->height;
+}
+
+const struct custom_format format_grey = {
+    .output_row = output_row_grey,
+    .get_size = get_size_grey
+};