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Diffstat (limited to 'graphics/scaler/scalebit.cpp')
-rw-r--r-- | graphics/scaler/scalebit.cpp | 357 |
1 files changed, 357 insertions, 0 deletions
diff --git a/graphics/scaler/scalebit.cpp b/graphics/scaler/scalebit.cpp new file mode 100644 index 0000000000..71d9172534 --- /dev/null +++ b/graphics/scaler/scalebit.cpp @@ -0,0 +1,357 @@ +/* + * This file is part of the Scale2x project. + * + * Copyright (C) 2003 Andrea Mazzoleni + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +/* + * This file contains an example implementation of the Scale effect + * applyed to a generic bitmap. + * + * You can find an high level description of the effect at : + * + * http://scale2x.sourceforge.net/ + * + * Alternatively at the previous license terms, you are allowed to use this + * code in your program with these conditions: + * - the program is not used in commercial activities. + * - the whole source code of the program is released with the binary. + * - derivative works of the program are allowed. + */ + +#if defined(HAVE_CONFIG_H) +#include <config.h> +#endif + +#include "common/scaler/intern.h" + +#include "scale2x.h" +#include "scale3x.h" + +#if defined(HAVE_ALLOCA_H) +#include <alloca.h> +#endif + +#include <assert.h> +#include <stdlib.h> + +#define DST(bits, num) (scale2x_uint ## bits *)dst ## num +#define SRC(bits, num) (const scale2x_uint ## bits *)src ## num + +/** + * Apply the Scale2x effect on a group of rows. Used internally. + */ +static inline void stage_scale2x(void* dst0, void* dst1, const void* src0, const void* src1, const void* src2, unsigned pixel, unsigned pixel_per_row) +{ + switch (pixel) { +#if defined(__GNUC__) && defined(__i386__) + case 1 : scale2x_8_mmx(DST(8,0), DST(8,1), SRC(8,0), SRC(8,1), SRC(8,2), pixel_per_row); break; + case 2 : scale2x_16_mmx(DST(16,0), DST(16,1), SRC(16,0), SRC(16,1), SRC(16,2), pixel_per_row); break; + case 4 : scale2x_32_mmx(DST(32,0), DST(32,1), SRC(32,0), SRC(32,1), SRC(32,2), pixel_per_row); break; +#else + case 1 : scale2x_8_def(DST(8,0), DST(8,1), SRC(8,0), SRC(8,1), SRC(8,2), pixel_per_row); break; + case 2 : scale2x_16_def(DST(16,0), DST(16,1), SRC(16,0), SRC(16,1), SRC(16,2), pixel_per_row); break; + case 4 : scale2x_32_def(DST(32,0), DST(32,1), SRC(32,0), SRC(32,1), SRC(32,2), pixel_per_row); break; +#endif + } +} + +/** + * Apply the Scale3x effect on a group of rows. Used internally. + */ +static inline void stage_scale3x(void* dst0, void* dst1, void* dst2, const void* src0, const void* src1, const void* src2, unsigned pixel, unsigned pixel_per_row) +{ + switch (pixel) { + case 1 : scale3x_8_def(DST(8,0), DST(8,1), DST(8,2), SRC(8,0), SRC(8,1), SRC(8,2), pixel_per_row); break; + case 2 : scale3x_16_def(DST(16,0), DST(16,1), DST(16,2), SRC(16,0), SRC(16,1), SRC(16,2), pixel_per_row); break; + case 4 : scale3x_32_def(DST(32,0), DST(32,1), DST(32,2), SRC(32,0), SRC(32,1), SRC(32,2), pixel_per_row); break; + } +} + +/** + * Apply the Scale4x effect on a group of rows. Used internally. + */ +static inline void stage_scale4x(void* dst0, void* dst1, void* dst2, void* dst3, const void* src0, const void* src1, const void* src2, const void* src3, unsigned pixel, unsigned pixel_per_row) +{ + stage_scale2x(dst0, dst1, src0, src1, src2, pixel, 2 * pixel_per_row); + stage_scale2x(dst2, dst3, src1, src2, src3, pixel, 2 * pixel_per_row); +} + +#define SCDST(i) (dst+(i)*dst_slice) +#define SCSRC(i) (src+(i)*src_slice) +#define SCMID(i) (mid[(i)]) + +/** + * Apply the Scale2x effect on a bitmap. + * The destination bitmap is filled with the scaled version of the source bitmap. + * The source bitmap isn't modified. + * The destination bitmap must be manually allocated before calling the function, + * note that the resulting size is exactly 2x2 times the size of the source bitmap. + * \param void_dst Pointer at the first pixel of the destination bitmap. + * \param dst_slice Size in bytes of a destination bitmap row. + * \param void_src Pointer at the first pixel of the source bitmap. + * \param src_slice Size in bytes of a source bitmap row. + * \param pixel Bytes per pixel of the source and destination bitmap. + * \param width Horizontal size in pixels of the source bitmap. + * \param height Vertical size in pixels of the source bitmap. + */ +static void scale2x(void* void_dst, unsigned dst_slice, const void* void_src, unsigned src_slice, unsigned pixel, unsigned width, unsigned height) +{ + unsigned char* dst = (unsigned char*)void_dst; + const unsigned char* src = (const unsigned char*)void_src; + unsigned count; + + assert(height >= 2); + + count = height; + + while (count) { + stage_scale2x(SCDST(0), SCDST(1), SCSRC(0), SCSRC(1), SCSRC(2), pixel, width); + + dst = SCDST(2); + src = SCSRC(1); + + --count; + } + +#if defined(__GNUC__) && defined(__i386__) + scale2x_mmx_emms(); +#endif +} + +/** + * Apply the Scale32x effect on a bitmap. + * The destination bitmap is filled with the scaled version of the source bitmap. + * The source bitmap isn't modified. + * The destination bitmap must be manually allocated before calling the function, + * note that the resulting size is exactly 3x3 times the size of the source bitmap. + * \param void_dst Pointer at the first pixel of the destination bitmap. + * \param dst_slice Size in bytes of a destination bitmap row. + * \param void_src Pointer at the first pixel of the source bitmap. + * \param src_slice Size in bytes of a source bitmap row. + * \param pixel Bytes per pixel of the source and destination bitmap. + * \param width Horizontal size in pixels of the source bitmap. + * \param height Vertical size in pixels of the source bitmap. + */ +static void scale3x(void* void_dst, unsigned dst_slice, const void* void_src, unsigned src_slice, unsigned pixel, unsigned width, unsigned height) +{ + unsigned char* dst = (unsigned char*)void_dst; + const unsigned char* src = (const unsigned char*)void_src; + unsigned count; + + assert(height >= 2); + + count = height; + + while (count) { + stage_scale3x(SCDST(0), SCDST(1), SCDST(2), SCSRC(0), SCSRC(1), SCSRC(2), pixel, width); + + dst = SCDST(3); + src = SCSRC(1); + + --count; + } +} + +/** + * Apply the Scale4x effect on a bitmap. + * The destination bitmap is filled with the scaled version of the source bitmap. + * The source bitmap isn't modified. + * The destination bitmap must be manually allocated before calling the function, + * note that the resulting size is exactly 4x4 times the size of the source bitmap. + * \note This function requires also a small buffer bitmap used internally to store + * intermediate results. This bitmap must have at least an horizontal size in bytes of 2*width*pixel, + * and a vertical size of 6 rows. The memory of this buffer must not be allocated + * in video memory because it's also read and not only written. Generally + * a heap (malloc) or a stack (alloca) buffer is the best choices. + * \param void_dst Pointer at the first pixel of the destination bitmap. + * \param dst_slice Size in bytes of a destination bitmap row. + * \param void_mid Pointer at the first pixel of the buffer bitmap. + * \param mid_slice Size in bytes of a buffer bitmap row. + * \param void_src Pointer at the first pixel of the source bitmap. + * \param src_slice Size in bytes of a source bitmap row. + * \param pixel Bytes per pixel of the source and destination bitmap. + * \param width Horizontal size in pixels of the source bitmap. + * \param height Vertical size in pixels of the source bitmap. + */ +static void scale4x_buf(void* void_dst, unsigned dst_slice, void* void_mid, unsigned mid_slice, const void* void_src, unsigned src_slice, unsigned pixel, unsigned width, unsigned height) +{ + unsigned char* dst = (unsigned char*)void_dst; + const unsigned char* src = (const unsigned char*)void_src; + unsigned count; + unsigned char* mid[6]; + + assert(height >= 4); + + count = height; + + /* set the 6 buffer pointers */ + mid[0] = (unsigned char*)void_mid; + mid[1] = mid[0] + mid_slice; + mid[2] = mid[1] + mid_slice; + mid[3] = mid[2] + mid_slice; + mid[4] = mid[3] + mid_slice; + mid[5] = mid[4] + mid_slice; + + while (count) { + unsigned char* tmp; + + stage_scale2x(SCMID(4), SCMID(5), SCSRC(2), SCSRC(3), SCSRC(4), pixel, width); + stage_scale4x(SCDST(0), SCDST(1), SCDST(2), SCDST(3), SCMID(1), SCMID(2), SCMID(3), SCMID(4), pixel, width); + + dst = SCDST(4); + src = SCSRC(1); + + tmp = SCMID(0); /* shift by 2 position */ + SCMID(0) = SCMID(2); + SCMID(2) = SCMID(4); + SCMID(4) = tmp; + tmp = SCMID(1); + SCMID(1) = SCMID(3); + SCMID(3) = SCMID(5); + SCMID(5) = tmp; + + --count; + } + +#if defined(__GNUC__) && defined(__i386__) + scale2x_mmx_emms(); +#endif +} + +/** + * Apply the Scale4x effect on a bitmap. + * The destination bitmap is filled with the scaled version of the source bitmap. + * The source bitmap isn't modified. + * The destination bitmap must be manually allocated before calling the function, + * note that the resulting size is exactly 4x4 times the size of the source bitmap. + * \note This function operates like ::scale4x_buf() but the intermediate buffer is + * automatically allocated in the stack. + * \param void_dst Pointer at the first pixel of the destination bitmap. + * \param dst_slice Size in bytes of a destination bitmap row. + * \param void_src Pointer at the first pixel of the source bitmap. + * \param src_slice Size in bytes of a source bitmap row. + * \param pixel Bytes per pixel of the source and destination bitmap. + * \param width Horizontal size in pixels of the source bitmap. + * \param height Vertical size in pixels of the source bitmap. + */ +static void scale4x(void* void_dst, unsigned dst_slice, const void* void_src, unsigned src_slice, unsigned pixel, unsigned width, unsigned height) +{ + unsigned mid_slice; + void* mid; + + mid_slice = 2 * pixel * width; /* required space for 1 row buffer */ + + mid_slice = (mid_slice + 0x7) & ~0x7; /* align to 8 bytes */ + +#if defined(HAVE_ALLOCA) + mid = alloca(6 * mid_slice); /* allocate space for 6 row buffers */ + + assert(mid != 0); /* alloca should never fails */ +#else + mid = malloc(6 * mid_slice); /* allocate space for 6 row buffers */ + + if (!mid) + return; +#endif + + scale4x_buf(void_dst, dst_slice, mid, mid_slice, void_src, src_slice, pixel, width, height); + +#if !defined(HAVE_ALLOCA) + free(mid); +#endif +} + +/** + * Check if the scale implementation is applicable at the given arguments. + * \param scale Scale factor. 2, 3 or 4. + * \param pixel Bytes per pixel of the source and destination bitmap. + * \param width Horizontal size in pixels of the source bitmap. + * \param height Vertical size in pixels of the source bitmap. + * \return + * - -1 on precondition violated. + * - 0 on success. + */ +int scale_precondition(unsigned scale, unsigned pixel, unsigned width, unsigned height) +{ + if (scale != 2 && scale != 3 && scale != 4) + return -1; + + if (pixel != 1 && pixel != 2 && pixel != 4) + return -1; + + switch (scale) { + case 2 : + case 3 : + if (height < 2) + return -1; + break; + case 4 : + if (height < 4) + return -1; + break; + } + +#if defined(__GNUC__) && defined(__i386__) + switch (scale) { + case 2 : + case 4 : + if (width < (16 / pixel)) + return -1; + if (width % (8 / pixel) != 0) + return -1; + break; + case 3 : + if (width < 2) + return -1; + break; + } +#else + if (width < 2) + return -1; +#endif + + return 0; +} + +/** + * Apply the Scale effect on a bitmap. + * This function is simply a common interface for ::scale2x(), ::scale3x() and ::scale4x(). + * \param scale Scale factor. 2, 3 or 4. + * \param void_dst Pointer at the first pixel of the destination bitmap. + * \param dst_slice Size in bytes of a destination bitmap row. + * \param void_src Pointer at the first pixel of the source bitmap. + * \param src_slice Size in bytes of a source bitmap row. + * \param pixel Bytes per pixel of the source and destination bitmap. + * \param width Horizontal size in pixels of the source bitmap. + * \param height Vertical size in pixels of the source bitmap. + */ +void scale(unsigned scale, void* void_dst, unsigned dst_slice, const void* void_src, unsigned src_slice, unsigned pixel, unsigned width, unsigned height) +{ + switch (scale) { + case 2 : + scale2x(void_dst, dst_slice, void_src, src_slice, pixel, width, height); + break; + case 3 : + scale3x(void_dst, dst_slice, void_src, src_slice, pixel, width, height); + break; + case 4 : + scale4x(void_dst, dst_slice, void_src, src_slice, pixel, width, height); + break; + } +} + |