/*

Simple DirectMedia Layer

Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>

This software is provided 'as-is', without any express or implied

warranty. In no event will the authors be held liable for any damages

arising from the use of this software.

Permission is granted to anyone to use this software for any purpose,

including commercial applications, and to alter it and redistribute it

freely, subject to the following restrictions:

1. The origin of this software must not be misrepresented; you must not

claim that you wrote the original software. If you use this software

in a product, an acknowledgment in the product documentation would be

appreciated but is not required.

2. Altered source versions must be plainly marked as such, and must not be

misrepresented as being the original software.

3. This notice may not be removed or altered from any source distribution.

*/

#include "../SDL_internal.h"

#if SDL_HAVE_BLIT_0

#include "SDL_video.h"

#include "SDL_blit.h"

/* Functions to blit from bitmaps to other surfaces */

static void

BlitBto1(SDL_BlitInfo * info)

{

int c;

int width, height;

Uint8 *src, *map, *dst;

int srcskip, dstskip;

/* Set up some basic variables */

width = info->dst_w;

height = info->dst_h;

src = info->src;

srcskip = info->src_skip;

dst = info->dst;

dstskip = info->dst_skip;

map = info->table;

srcskip += width - (width + 7) / 8;

if (map) {

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (1) {

*dst = map[bit];

}

dst++;

byte <<= 1;

}

src += srcskip;

dst += dstskip;

}

} else {

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (1) {

*dst = bit;

}

dst++;

byte <<= 1;

}

src += srcskip;

dst += dstskip;

}

}

}

static void

BlitBto2(SDL_BlitInfo * info)

{

int c;

int width, height;

Uint8 *src;

Uint16 *map, *dst;

int srcskip, dstskip;

/* Set up some basic variables */

width = info->dst_w;

height = info->dst_h;

src = info->src;

srcskip = info->src_skip;

dst = (Uint16 *) info->dst;

dstskip = info->dst_skip / 2;

map = (Uint16 *) info->table;

srcskip += width - (width + 7) / 8;

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (1) {

*dst = map[bit];

}

byte <<= 1;

dst++;

}

src += srcskip;

dst += dstskip;

}

}

static void

BlitBto3(SDL_BlitInfo * info)

{

int c, o;

int width, height;

Uint8 *src, *map, *dst;

int srcskip, dstskip;

/* Set up some basic variables */

width = info->dst_w;

height = info->dst_h;

src = info->src;

srcskip = info->src_skip;

dst = info->dst;

dstskip = info->dst_skip;

map = info->table;

srcskip += width - (width + 7) / 8;

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (1) {

o = bit * 4;

dst[0] = map[o++];

dst[1] = map[o++];

dst[2] = map[o++];

}

byte <<= 1;

dst += 3;

}

src += srcskip;

dst += dstskip;

}

}

static void

BlitBto4(SDL_BlitInfo * info)

{

int width, height;

Uint8 *src;

Uint32 *map, *dst;

int srcskip, dstskip;

int c;

/* Set up some basic variables */

width = info->dst_w;

height = info->dst_h;

src = info->src;

srcskip = info->src_skip;

dst = (Uint32 *) info->dst;

dstskip = info->dst_skip / 4;

map = (Uint32 *) info->table;

srcskip += width - (width + 7) / 8;

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (1) {

*dst = map[bit];

}

byte <<= 1;

dst++;

}

src += srcskip;

dst += dstskip;

}

}

static void

BlitBto1Key(SDL_BlitInfo * info)

{

int width = info->dst_w;

int height = info->dst_h;

Uint8 *src = info->src;

Uint8 *dst = info->dst;

int srcskip = info->src_skip;

int dstskip = info->dst_skip;

Uint32 ckey = info->colorkey;

Uint8 *palmap = info->table;

int c;

/* Set up some basic variables */

srcskip += width - (width + 7) / 8;

if (palmap) {

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (bit != ckey) {

*dst = palmap[bit];

}

dst++;

byte <<= 1;

}

src += srcskip;

dst += dstskip;

}

} else {

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (bit != ckey) {

*dst = bit;

}

dst++;

byte <<= 1;

}

src += srcskip;

dst += dstskip;

}

}

}

static void

BlitBto2Key(SDL_BlitInfo * info)

{

int width = info->dst_w;

int height = info->dst_h;

Uint8 *src = info->src;

Uint16 *dstp = (Uint16 *) info->dst;

int srcskip = info->src_skip;

int dstskip = info->dst_skip;

Uint32 ckey = info->colorkey;

Uint8 *palmap = info->table;

int c;

/* Set up some basic variables */

srcskip += width - (width + 7) / 8;

dstskip /= 2;

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (bit != ckey) {

*dstp = ((Uint16 *) palmap)[bit];

}

byte <<= 1;

dstp++;

}

src += srcskip;

dstp += dstskip;

}

}

static void

BlitBto3Key(SDL_BlitInfo * info)

{

int width = info->dst_w;

int height = info->dst_h;

Uint8 *src = info->src;

Uint8 *dst = info->dst;

int srcskip = info->src_skip;

int dstskip = info->dst_skip;

Uint32 ckey = info->colorkey;

Uint8 *palmap = info->table;

int c;

/* Set up some basic variables */

srcskip += width - (width + 7) / 8;

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (bit != ckey) {

SDL_memcpy(dst, &palmap[bit * 4], 3);

}

byte <<= 1;

dst += 3;

}

src += srcskip;

dst += dstskip;

}

}

static void

BlitBto4Key(SDL_BlitInfo * info)

{

int width = info->dst_w;

int height = info->dst_h;

Uint8 *src = info->src;

Uint32 *dstp = (Uint32 *) info->dst;

int srcskip = info->src_skip;

int dstskip = info->dst_skip;

Uint32 ckey = info->colorkey;

Uint8 *palmap = info->table;

int c;

/* Set up some basic variables */

srcskip += width - (width + 7) / 8;

dstskip /= 4;

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (bit != ckey) {

*dstp = ((Uint32 *) palmap)[bit];

}

byte <<= 1;

dstp++;

}

src += srcskip;

dstp += dstskip;

}

}

static void

BlitBtoNAlpha(SDL_BlitInfo * info)

{

int width = info->dst_w;

int height = info->dst_h;

Uint8 *src = info->src;

Uint8 *dst = info->dst;

int srcskip = info->src_skip;

int dstskip = info->dst_skip;

const SDL_Color *srcpal = info->src_fmt->palette->colors;

SDL_PixelFormat *dstfmt = info->dst_fmt;

int dstbpp;

int c;

Uint32 pixel;

unsigned sR, sG, sB;

unsigned dR, dG, dB, dA;

const unsigned A = info->a;

/* Set up some basic variables */

dstbpp = dstfmt->BytesPerPixel;

srcskip += width - (width + 7) / 8;

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (1) {

sR = srcpal[bit].r;

sG = srcpal[bit].g;

sB = srcpal[bit].b;

DISEMBLE_RGBA(dst, dstbpp, dstfmt, pixel, dR, dG, dB, dA);

ALPHA_BLEND_RGBA(sR, sG, sB, A, dR, dG, dB, dA);

ASSEMBLE_RGBA(dst, dstbpp, dstfmt, dR, dG, dB, dA);

}

byte <<= 1;

dst += dstbpp;

}

src += srcskip;

dst += dstskip;

}

}

static void

BlitBtoNAlphaKey(SDL_BlitInfo * info)

{

int width = info->dst_w;

int height = info->dst_h;

Uint8 *src = info->src;

Uint8 *dst = info->dst;

int srcskip = info->src_skip;

int dstskip = info->dst_skip;

SDL_PixelFormat *srcfmt = info->src_fmt;

SDL_PixelFormat *dstfmt = info->dst_fmt;

const SDL_Color *srcpal = srcfmt->palette->colors;

int dstbpp;

int c;

Uint32 pixel;

unsigned sR, sG, sB;

unsigned dR, dG, dB, dA;

const unsigned A = info->a;

Uint32 ckey = info->colorkey;

/* Set up some basic variables */

dstbpp = dstfmt->BytesPerPixel;

srcskip += width - (width + 7) / 8;

while (height--) {

Uint8 byte = 0, bit;

for (c = 0; c < width; ++c) {

if ((c & 7) == 0) {

byte = *src++;

}

bit = (byte & 0x80) >> 7;

if (bit != ckey) {

sR = srcpal[bit].r;

sG = srcpal[bit].g;

sB = srcpal[bit].b;

DISEMBLE_RGBA(dst, dstbpp, dstfmt, pixel, dR, dG, dB, dA);

ALPHA_BLEND_RGBA(sR, sG, sB, A, dR, dG, dB, dA);

ASSEMBLE_RGBA(dst, dstbpp, dstfmt, dR, dG, dB, dA);

}

byte <<= 1;

dst += dstbpp;

}

src += srcskip;

dst += dstskip;

}

}

static const SDL_BlitFunc bitmap_blit[] = {

(SDL_BlitFunc) NULL, BlitBto1, BlitBto2, BlitBto3, BlitBto4

};

static const SDL_BlitFunc colorkey_blit[] = {

(SDL_BlitFunc) NULL, BlitBto1Key, BlitBto2Key, BlitBto3Key, BlitBto4Key

};

SDL_BlitFunc

SDL_CalculateBlit0(SDL_Surface * surface)

{

int which;

if (surface->format->BitsPerPixel != 1) {

/* We don't support sub 8-bit packed pixel modes */

return (SDL_BlitFunc) NULL;

}

if (surface->map->dst->format->BitsPerPixel < 8) {

which = 0;

} else {

which = surface->map->dst->format->BytesPerPixel;

}

switch (surface->map->info.flags & ~SDL_COPY_RLE_MASK) {

case 0:

return bitmap_blit[which];

case SDL_COPY_COLORKEY:

return colorkey_blit[which];

case SDL_COPY_MODULATE_ALPHA | SDL_COPY_BLEND:

return which >= 2 ? BlitBtoNAlpha : (SDL_BlitFunc) NULL;

case SDL_COPY_COLORKEY | SDL_COPY_MODULATE_ALPHA | SDL_COPY_BLEND:

return which >= 2 ? BlitBtoNAlphaKey : (SDL_BlitFunc) NULL;

}

return (SDL_BlitFunc) NULL;

}

#endif /* SDL_HAVE_BLIT_0 */

/* vi: set ts=4 sw=4 expandtab: */