diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/fonts/Makefile | 1 | ||||
| -rw-r--r-- | lib/fonts/font_rotate.c | 150 |
2 files changed, 151 insertions, 0 deletions
diff --git a/lib/fonts/Makefile b/lib/fonts/Makefile index b176af53d53e..7202a70a56ef 100644 --- a/lib/fonts/Makefile +++ b/lib/fonts/Makefile @@ -2,6 +2,7 @@ # Font handling font-y := fonts.o +font-$(CONFIG_FRAMEBUFFER_CONSOLE_ROTATION) += font_rotate.o # Built-in fonts; sorted by Family-Size in ascending order font-$(CONFIG_FONT_6x8) += font_6x8.o diff --git a/lib/fonts/font_rotate.c b/lib/fonts/font_rotate.c new file mode 100644 index 000000000000..d107a8d0a2b0 --- /dev/null +++ b/lib/fonts/font_rotate.c @@ -0,0 +1,150 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Font rotation + * + * Copyright (C) 2005 Antonino Daplas <adaplas @pol.net> + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive for + * more details. + */ + +#include <linux/export.h> +#include <linux/math.h> +#include <linux/string.h> + +#include "font.h" + +static inline int pattern_test_bit(u32 x, u32 y, u32 pitch, const char *pat) +{ + u32 tmp = (y * pitch) + x, index = tmp / 8, bit = tmp % 8; + + pat += index; + return (*pat) & (0x80 >> bit); +} + +static inline void pattern_set_bit(u32 x, u32 y, u32 pitch, char *pat) +{ + u32 tmp = (y * pitch) + x, index = tmp / 8, bit = tmp % 8; + + pat += index; + + (*pat) |= 0x80 >> bit; +} + +static inline void rotate_cw(const char *in, char *out, u32 width, u32 height) +{ + int i, j, h = height, w = width; + int shift = (8 - (height % 8)) & 7; + + width = (width + 7) & ~7; + height = (height + 7) & ~7; + + for (i = 0; i < h; i++) { + for (j = 0; j < w; j++) { + if (pattern_test_bit(j, i, width, in)) + pattern_set_bit(height - 1 - i - shift, j, + height, out); + } + } +} + +/** + * font_glyph_rotate_90 - Rotate a glyph pattern by 90° in clockwise direction + * @glyph: The glyph to rotate + * @width: The glyph width in bits per scanline + * @height: The number of scanlines in the glyph + * @out: The rotated glyph bitmap + * + * The parameters @width and @height refer to the input glyph given in @glyph. + * The caller has to provide the output buffer @out of sufficient size to hold + * the rotated glyph. Rotating by 90° flips the width and height for the output + * glyph. Depending on the glyph pitch, the size of the output glyph can be + * different than the size of the input. Callers have to take this into account + * when allocating the output memory. + */ +void font_glyph_rotate_90(const unsigned char *glyph, unsigned int width, unsigned int height, + unsigned char *out) +{ + memset(out, 0, font_glyph_size(height, width)); /* flip width/height */ + + rotate_cw(glyph, out, width, height); +} +EXPORT_SYMBOL_GPL(font_glyph_rotate_90); + +static inline void rotate_ud(const char *in, char *out, u32 width, u32 height) +{ + int i, j; + int shift = (8 - (width % 8)) & 7; + + width = (width + 7) & ~7; + + for (i = 0; i < height; i++) { + for (j = 0; j < width - shift; j++) { + if (pattern_test_bit(j, i, width, in)) + pattern_set_bit(width - (1 + j + shift), + height - (1 + i), + width, out); + } + } +} + +/** + * font_glyph_rotate_180 - Rotate a glyph pattern by 180° + * @glyph: The glyph to rotate + * @width: The glyph width in bits per scanline + * @height: The number of scanlines in the glyph + * @out: The rotated glyph bitmap + * + * The parameters @width and @height refer to the input glyph given in @glyph. + * The caller has to provide the output buffer @out of sufficient size to hold + * the rotated glyph. + */ +void font_glyph_rotate_180(const unsigned char *glyph, unsigned int width, unsigned int height, + unsigned char *out) +{ + memset(out, 0, font_glyph_size(width, height)); + + rotate_ud(glyph, out, width, height); +} +EXPORT_SYMBOL_GPL(font_glyph_rotate_180); + +static inline void rotate_ccw(const char *in, char *out, u32 width, u32 height) +{ + int i, j, h = height, w = width; + int shift = (8 - (width % 8)) & 7; + + width = (width + 7) & ~7; + height = (height + 7) & ~7; + + for (i = 0; i < h; i++) { + for (j = 0; j < w; j++) { + if (pattern_test_bit(j, i, width, in)) + pattern_set_bit(i, width - 1 - j - shift, + height, out); + } + } +} + +/** + * font_glyph_rotate_270 - Rotate a glyph pattern by 270° in clockwise direction + * @glyph: The glyph to rotate + * @width: The glyph width in bits per scanline + * @height: The number of scanlines in the glyph + * @out: The rotated glyph bitmap + * + * The parameters @width and @height refer to the input glyph given in @glyph. + * The caller has to provide the output buffer @out of sufficient size to hold + * the rotated glyph. Rotating by 270° flips the width and height for the output + * glyph. Depending on the glyph pitch, the size of the output glyph can be + * different than the size of the input. Callers have to take this into account + * when allocating the output memory. + */ +void font_glyph_rotate_270(const unsigned char *glyph, unsigned int width, unsigned int height, + unsigned char *out) +{ + memset(out, 0, font_glyph_size(height, width)); /* flip width/height */ + + rotate_ccw(glyph, out, width, height); +} +EXPORT_SYMBOL_GPL(font_glyph_rotate_270); |