/*** $Id: fblin4.c,v 1.19 2003/11/22 11:49:29 weiym Exp $** ** fblin4.c: Frame buffer 4 bpp Linear Video Driver for MiniGUI**  This driver is suitable for the most significant bit being right.** ** Copyright (C) 2003, Feynman Software.** Copyright (C) 2001, Song Lixin and Wei Yongming.**** 2001/01/17: Created by Song Lixin **** 2003/07/11: Cleanup by Wei Yongming.*//*** 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA*/#include <stdlib.h>#include <stdio.h>#include <string.h>#include "native.h"#include "fb.h"#ifdef _FBLIN4R_SUPPORT#define SHIFT(x) ((x&1)?4:0)static unsigned char pixmask [] = {0x0f, 0xf0};static unsigned char pixnotmask [] = {0xf0, 0x0f};static inline gal_uint8* get_pixel_address (PSD psd, int x, int y){    return (gal_uint8 *) psd->addr + y*psd->linelen + (x >> 1);}static inline void xsetpixel_in_byte (int x, gal_pixel c, gal_uint8 *byte){    *byte = (*byte & (pixnotmask[x&1])) | ((c << SHIFT(x))^(*byte & pixmask[x&1]));}static inline void setpixel_in_byte (int x, gal_pixel c, gal_uint8 *byte){    *byte = (*byte & (pixnotmask[x&1])) | (c << SHIFT(x));}static inline gal_pixel getpixel_in_byte (int x, const gal_uint8 *byte){    gal_uint8 tmp = *byte;    tmp = tmp & pixmask [x&1];    return (tmp >> SHIFT(x));}static int fblin4_init (PSD psd){    if (!psd->size) {        psd->size = psd->yres * psd->linelen;        return 1;    }    return 1;}/* Set pixel at x, y, to gal_pixel c*/static void fblin4_drawpixel (PSD psd, int x, int y, gal_pixel c){    if (psd->gr_mode == MODE_XOR)        xsetpixel_in_byte (x, c, get_pixel_address (psd, x, y));    else        setpixel_in_byte (x, c, get_pixel_address (psd, x, y));}/* Read pixel at x, y*/static gal_pixel fblin4_readpixel (PSD psd, int x, int y){    return getpixel_in_byte (x, get_pixel_address (psd, x, y));}/* Draw horizontal line from x1,y to x2,y including final point*/static void fblin4_drawhline (PSD psd, int x, int y, int w, gal_pixel c){    gal_uint8 *addr;    gal_uint8 cc;    c = c & 0x0f;    cc = c | (c << 4);    addr = get_pixel_address (psd, x, y);    if (psd->gr_mode == MODE_XOR) {        if (x & 1) {            xsetpixel_in_byte (1, c, addr);            addr++;            w--;        }        while (w > 1) {            *addr++ ^= cc ;            w -= 2;        }        if (w > 0)             xsetpixel_in_byte (0, c, addr);    } else {        if (x & 1) {            setpixel_in_byte (1, c, addr);            addr++;            w--;        }        while (w > 1) {            *addr++ = cc ;            w -= 2;        }        if (w > 0)             setpixel_in_byte (0, c, addr);    }}static void fblin4_drawvline (PSD psd, int x, int y, int h, gal_pixel c){    gal_uint8* addr;    addr = get_pixel_address (psd, x, y);    if (psd->gr_mode == MODE_XOR) {        while (h--) {            xsetpixel_in_byte (x, c, addr);            addr += psd->linelen;        }    }    else {        while (h--) {            setpixel_in_byte (x, c, addr);            addr += psd->linelen;        }    }}/* clip to screen */static void fblin4_getbox (PSD psd, int x, int y, int w, int h, void* buf){    int i;    gal_uint8 *dst = (gal_uint8*) buf;    const gal_uint8 *src;    int d_pitch = w;    if (y < 0) {        h += y;        dst += -y * d_pitch;        y = 0;    }    if (x < 0) {        w += x;        dst += -x;        x = 0;    }            if (y + h  - 1 >= psd->yres)         h = psd->yres - y ;    if (x + w  - 1 >= psd->xres)         w = psd->xres - x ;    if (w <= 0 || h <= 0) return;    w += x;    src = get_pixel_address (psd, x, y);    while (h--) {        const gal_uint8 *s_line = src;        gal_uint8 *d_line = dst;        i = x;        while (i < w) {            *d_line = getpixel_in_byte (i, s_line);            d_line++; i++;            if (!(i&1)) s_line++;        }        src += psd->linelen;        dst += d_pitch;    }}/* do clip */static void fblin4_putbox (PSD psd, int x, int y, int w, int h, void *buf){    int i;    const gal_uint8 *src = (gal_uint8*) buf;    gal_uint8 *dst;    int s_pitch = w;    if (psd->doclip) {        if (y < psd->clipminy) {            h -= psd->clipminy - y;            src += (psd->clipminy - y) * s_pitch;            y = psd->clipminy;        }        if (x < psd->clipminx) {            w -= psd->clipminx - x;            src += psd->clipminx - x;            x = psd->clipminx;        }        if (y + h - 1 >= psd->clipmaxy)            h = psd->clipmaxy- y;        if (x + w - 1 >= psd->clipmaxx)            w = psd->clipmaxx- x;    }    else {        if ( y < 0 ) {            h += y;            src += -y * s_pitch;            y = 0;        }        if ( x < 0 ) {            w += x;            src += -x;            x = 0;        }        if ( y + h  -1 >= psd->yres)            h = psd->yres - y;        if ( x + w  -1 >= psd->xres)            w = psd->xres - x;    }    if (w <= 0 || h <= 0) return;    w += x;    dst = get_pixel_address (psd, x, y);    while (h--) {        const gal_uint8 *s_line = src;        gal_uint8 *d_line = dst;        i = x;        while (i < w) {            setpixel_in_byte (i, *s_line & 0x0F, d_line);            s_line ++; i ++;            if (!(i&1)) d_line++;        }        dst += psd->linelen;        src += s_pitch;    }}static void fblin4_putboxmask (PSD psd, int x, int y, int w, int h, void *buf, gal_pixel cxx){    int i;    gal_uint8 *src = (gal_uint8*) buf;    gal_uint8 *dst;    int s_pitch =  w ;    if (psd->doclip) {            if (y < psd->clipminy) {            h -= psd->clipminy - y;            src += (psd->clipminy - y) * s_pitch;            y = psd->clipminy;        }        if (x < psd->clipminx) {            w -= psd->clipminx - x;            src += psd->clipminx - x;            x = psd->clipminx;        }                if (y + h - 1 >= psd->clipmaxy)             h =  psd->clipmaxy- y;        if (x + w - 1 >= psd->clipmaxx)             w =  psd->clipmaxx- x;    }    else {        if ( y < 0 ) {            h += y;            src += -y * s_pitch;            y = 0;        }        if ( x < 0 ) {            w += x;            src += -x;            x = 0;        }                if ( y + h  -1 >= psd->yres)             h = psd->yres - y ;        if ( x + w  -1 >= psd->xres)             w = psd->xres - x ;    }    if (w <= 0 || h <= 0) return;    cxx = cxx & 0x0f;    w += x;    dst = get_pixel_address (psd, x, y);    while (h--) {        gal_uint8 *s_line = src;        gal_uint8 *d_line = dst;        i = x;        while (i < w) {            gal_uint8 spix = *s_line & 0x0f;            if (spix != cxx)                setpixel_in_byte (i, spix, d_line);            s_line++; i++;            if (!(i&1)) d_line ++;        }        dst += psd->linelen;        src += s_pitch;    }}static unsigned char right_side_mask [] = {0xff, 0xf0};static unsigned char left_side_mask [] = {0x00, 0x0f};static unsigned char right_ban_mask [] = {0x00, 0xf0};static unsigned char left_ban_mask [] = {0x00, 0x0f};static void fblin4_copyline_lr (gal_uint8 *src, int x1, gal_uint8 *dst, int x2, int w){    int s_head = x1 & 1;    int d_head = x2 & 1;    if (s_head == d_head) {        if (d_head) {            *dst = (*src & right_side_mask [d_head]) | (*dst & left_side_mask [d_head]);            src ++; dst ++; w--;        }        while (w > 1) {            *dst++ = *src++;            w -= 2;        }        if (w) {            *dst = (*src & left_side_mask [w]) | (*dst & (right_side_mask [w]));        }    }    else if (d_head > s_head) {        gal_uint8 sl_half = *src << 4;        gal_uint8 sr_half;        gal_uint8 sb_new;        *dst = (sl_half & right_side_mask [d_head]) | (*dst & left_side_mask [d_head]);        dst++;        w--;        sr_half = *src & right_ban_mask [1];        while (w > 1) {            src++;            sl_half = *src << 4;            sb_new = sl_half | (sr_half >> 4);            sr_half = *src & right_ban_mask [1];            *dst = sb_new;            dst++;             w -= 2;        }        if (w) {            sr_half = *src & right_ban_mask [1];            src++;            sl_half = *src << 4;            sb_new = sl_half | (sr_half >> 4);            *dst = (sb_new & left_side_mask [w]) | (*dst & right_side_mask[w]);        }    }    else /* s_head > d_head */    {        gal_uint8 sl_half;        gal_uint8 sr_half;        gal_uint8 sb_new;        while (w > 1) {            sl_half = *src >> 4;            sr_half = *(++src) & (left_ban_mask [1]);            sb_new = sl_half | (sr_half << 4);            *dst = sb_new;            dst++;             w -= 2;        }        if (w) {            sl_half = *src >> 4;            sr_half = *(++src) & (left_ban_mask [1]);            sb_new = sl_half | (sr_half << 4);            *dst = (sb_new & left_side_mask [w]) | (*dst & right_side_mask[w]);        }    }}static void fblin4_copybox (PSD psd,int x1, int y1, int w, int h, int x2, int y2){    register gal_uint8 *src, *dst;    register int linelen = psd->linelen;    if (y1 == y2) {        if (x1 < x2 && x1 + w > x2) {            //gal_uint8 *tmp = alloca (w >> 1);            gal_uint8 *tmp = malloc (w >> 1);            src= psd->addr + y1 * linelen + (x1 >> 1);            dst= psd->addr + y2 * linelen + (x2 >> 1);            while (h) {                fblin4_copyline_lr (src, x1, tmp, 0, w);                fblin4_copyline_lr (tmp, 0, dst, x2, w);                src += linelen;                dst += linelen;                h--;            }            free (tmp);        }        else {            src= psd->addr + y1 * linelen + (x1 >> 1);            dst= psd->addr + y2 * linelen + (x2 >> 1);            while (h) {                fblin4_copyline_lr (src, x1, dst, x2, w);                src += linelen;                dst += linelen;            }        }    }    else if (y1 < y2 && y1 + h >= y2) {        y1 += (h-1);        y2 += (h-1);        src = psd->addr + y1 * linelen + (x1 >> 1);        dst = psd->addr + y2 * linelen + (x2 >> 1);        while (h) {            fblin4_copyline_lr (src, x1, dst, x2, w);            src -= linelen;            dst -= linelen;            h--;        }    }    else {        src= psd->addr + y1 * linelen + (x1 >> 1);        dst= psd->addr + y2 * linelen + (x2 >> 1);        while (h) {            fblin4_copyline_lr (src, x1, dst, x2, w);            src += linelen;            dst += linelen;            h--;        }    }}/* blit, no clipping */static void fblin4_blit (PSD dstpsd, int dstx, int dsty, int w, int h,    PSD srcpsd, int srcx, int srcy){    gal_uint8* dst;    gal_uint8* src;    dst = get_pixel_address (dstpsd, dstx, dsty);    src = get_pixel_address (srcpsd, srcx, srcy);    while (h) {        fblin4_copyline_lr (src, srcx, dst, dstx, w);        src += srcpsd->linelen;        dst += dstpsd->linelen;        h--;    }}SUBDRIVER fblinear4 = {    fblin4_init,    fblin4_drawpixel,    fblin4_readpixel,    fblin4_drawhline,    fblin4_drawvline,    fblin4_blit,    fblin4_putbox,    fblin4_getbox,    fblin4_putboxmask,    fblin4_copybox};#endif /* _FBLIN4R_SUPPORT */