Use RLE coding scheme for glyph bitmaps.

Rather than generating fz_pixmaps for glyphs, we generate fz_glyphs.
fz_glyphs can either contain a pixmap, or an RLEd representation
(if it's a mask, and it's smaller).

Should take less memory in the cache, and should be faster to plot.

1 files changed, 137 insertions, 0 deletions

diff --git a/include/mupdf/fitz/glyph.h b/include/mupdf/fitz/glyph.h
new file mode 100644
index 00000000..f2cc6cc1
--- /dev/null
+++ b/include/mupdf/fitz/glyph.h
@@ -0,0 +1,137 @@
+#ifndef MUPDF_FITZ_GLYPH_H
+#define MUPDF_FITZ_GLYPH_H
+
+#include "mupdf/fitz/system.h"
+#include "mupdf/fitz/context.h"
+#include "mupdf/fitz/math.h"
+#include "mupdf/fitz/store.h"
+#include "mupdf/fitz/colorspace.h"
+
+/*
+	Glyphs represent a run length encoded set of pixels for a 2
+	dimensional region of a plane.
+*/
+typedef struct fz_glyph_s fz_glyph;
+
+/*
+	fz_glyph_bbox: Return the bounding box for a glyph.
+*/
+fz_irect *fz_glyph_bbox(fz_context *ctx, fz_glyph *glyph, fz_irect *bbox);
+
+/*
+	fz_glyph_width: Return the width of the glyph in pixels.
+*/
+int fz_glyph_width(fz_context *ctx, fz_glyph *glyph);
+
+/*
+	fz_glyph_height: Return the height of the glyph in pixels.
+*/
+int fz_glyph_height(fz_context *ctx, fz_glyph *glyph);
+
+/*
+	fz_new_glyph_from_pixmap: Create a new glyph from a pixmap
+
+	Returns a pointer to the new glyph. Throws exception on failure to
+	allocate.
+*/
+fz_glyph *fz_new_glyph_from_pixmap(fz_context *ctx, fz_pixmap *pix);
+
+/*
+	fz_new_glyph_from_8bpp_data: Create a new glyph from 8bpp data
+
+	x, y: X and Y position for the glyph
+
+	w, h: Width and Height for the glyph
+
+	sp: Source Pointer to data
+
+	span: Increment from line to line of data
+
+	Returns a pointer to the new glyph. Throws exception on failure to
+	allocate.
+*/
+fz_glyph *fz_new_glyph_from_8bpp_data(fz_context *ctx, int x, int y, int w, int h, unsigned char *sp, int span);
+
+/*
+	fz_new_glyph_from_1bpp_data: Create a new glyph from 1bpp data
+
+	x, y: X and Y position for the glyph
+
+	w, h: Width and Height for the glyph
+
+	sp: Source Pointer to data
+
+	span: Increment from line to line of data
+
+	Returns a pointer to the new glyph. Throws exception on failure to
+	allocate.
+*/fz_glyph *fz_new_glyph_from_1bpp_data(fz_context *ctx, int x, int y, int w, int h, unsigned char *sp, int span);
+
+
+/*
+	fz_keep_glyph: Take a reference to a glyph.
+
+	pix: The glyph to increment the reference for.
+
+	Returns pix. Does not throw exceptions.
+*/
+fz_glyph *fz_keep_glyph(fz_context *ctx, fz_glyph *pix);
+
+/*
+	fz_drop_glyph: Drop a reference and free a glyph.
+
+	Decrement the reference count for the glyph. When no
+	references remain the glyph will be freed.
+
+	Does not throw exceptions.
+*/
+void fz_drop_glyph(fz_context *ctx, fz_glyph *pix);
+
+/*
+	Glyphs represent a set of pixels for a 2 dimensional region of a
+	plane.
+
+	x, y: The minimum x and y coord of the region in pixels.
+
+	w, h: The width and height of the region in pixels.
+
+	samples: The sample data. The sample data is in a compressed format
+	designed to give reasonable compression, and to be fast to plot from.
+
+	The first sizeof(int) * h bytes of the table, when interpreted as
+	ints gives the offset within the data block of that lines data. An
+	offset of 0 indicates that that line is completely blank.
+
+	The data for individual lines is a sequence of bytes:
+	 00000000 = end of lines data
+	 LLLLLL00 = extend the length given in the next run by the 6 L bits
+		given here.
+	 LLLLLL01 = A run of length L+1 transparent pixels.
+	 LLLLLE10 = A run of length L+1 solid pixels. If E then this is the
+		last run on this line.
+	 LLLLLE11 = A run of length L+1 intermediate pixels followed by L+1
+		bytes of literal pixel data. If E then this is the last run
+		on this line.
+*/
+struct fz_glyph_s
+{
+	fz_storable storable;
+	int x, y, w, h;
+	fz_pixmap *pixmap;
+	int size;
+	unsigned char data[1];
+};
+
+static unsigned int fz_glyph_size(fz_context *ctx, fz_glyph *glyph);
+
+fz_irect *fz_glyph_bbox_no_ctx(fz_glyph *src, fz_irect *bbox);
+
+static inline unsigned int
+fz_glyph_size(fz_context *ctx, fz_glyph *glyph)
+{
+	if (glyph == NULL)
+		return 0;
+	return sizeof(fz_glyph) + glyph->size + fz_pixmap_size(ctx, glyph->pixmap);
+}
+
+#endif