/*

SDL - Simple DirectMedia Layer

Copyright (C) 1997-2004 Sam Lantinga

This library is free software; you can redistribute it and/or

modify it under the terms of the GNU Library General Public

License as published by the Free Software Foundation; either

version 2 of the License, or (at your option) any later version.

This library 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

Library General Public License for more details.

You should have received a copy of the GNU Library General Public

License along with this library; if not, write to the Free

Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

Sam Lantinga

slouken@libsdl.org

*/

#include "SDL_config.h"

/*

File added by Alan Buckley (alan_baa@hotmail.com) for RISC OS compatability

27 March 2003

Implements Sprite plotting code for wimp display.window

*/

#include "kernel.h"

#include "swis.h"

#include "SDL_stdinc.h"

#include "SDL_riscosvideo.h"

extern void WIMP_ReadModeInfo(_THIS);

void WIMP_PaletteChanged(_THIS);

/* Create sprite buffer for screen */

unsigned char *WIMP_CreateBuffer(int width, int height, int bpp)

{

int size;

char sprite_name[12] = "display";

unsigned char *buffer;

_kernel_swi_regs regs;

int bytesPerPixel;

int bytesPerRow;

int offsetToSpriteData = 60;

switch(bpp)

{

case 32: bytesPerPixel = 4; break;

case 16: bytesPerPixel = 2; break;

case 8:

bytesPerPixel = 1;

offsetToSpriteData += 2048; /* Add in size of palette */

break;

default:

return NULL;

break;

}

bytesPerRow = bytesPerPixel * width;

if ((bytesPerRow & 3) != 0)

{

bytesPerRow += 4 - (bytesPerRow & 3);

}

size = bytesPerRow * height;

buffer = SDL_malloc( (size_t) size + offsetToSpriteData );

if (!buffer) return NULL;

/* Initialise a sprite area */

*(unsigned int *)buffer = size + offsetToSpriteData;

*(unsigned int *)(buffer + 8) = 16;

regs.r[0] = 256+9;

regs.r[1] = (unsigned int)buffer;

_kernel_swi(OS_SpriteOp, &regs, &regs);

regs.r[0] = 256+15;

regs.r[1] = (unsigned int)buffer;

regs.r[2] = (unsigned int)&sprite_name;

regs.r[3] = 0; /* Palette flag: 0 = no palette */

regs.r[4] = width;

regs.r[5] = height;

if (bpp == 8)

{

/* Use old style mode number */

regs.r[6] = 28; /* 8bpp 90x90dpi */

} else

{

regs.r[6] = (((bpp == 16) ? 5 : 6) << 27) /* Type 6 = 32bpp sprite, 5 = 16bpp sprite */

| (90 << 14) /* Vertical dpi */

| (90 << 1) /* Horizontal dpi */

| 1; /* Marker to distinguish between mode selectors and sprite modes */

}

if (_kernel_swi(OS_SpriteOp, &regs, &regs) == NULL)

{

if (bpp == 8)

{

/* Modify sprite to take into account 256 colour palette */

int *sprite = (int *)(buffer + 16);

/* Adjust sprite offsets */

sprite[0] += 2048;

sprite[8] += 2048;

sprite[9] += 2048;

/* Adjust sprite area next free pointer */

(*(int *)(buffer+12)) += 2048;

/* Don't need to set up palette as SDL sets up the default

256 colour palette */

/* {

int *pal = sprite + 11;

unsigned int j;

unsigned int entry;

for (j = 0; j < 255; j++)

{

entry = (j << 24) | (j << 16) | (j << 8);

*pal++ = entry;

*pal++ = entry;

}

}

*/

}

} else

{

SDL_free(buffer);

buffer = NULL;

}

return buffer;

}

/* Setup translation buffers for the sprite plotting */

void WIMP_SetupPlotInfo(_THIS)

{

_kernel_swi_regs regs;

int *sprite = ((int *)this->hidden->bank[1])+4;

regs.r[0] = (unsigned int)this->hidden->bank[1];

regs.r[1] = (unsigned int)sprite;

regs.r[2] = -1; /* Current mode */

regs.r[3] = -1; /* Current palette */

regs.r[4] = 0; /* Get size of buffer */

regs.r[5] = 1|2|16; /* R1 - pointer to sprite and can use full palette words */

regs.r[6] = 0;

regs.r[7] = 0;

if (this->hidden->pixtrans) SDL_free(this->hidden->pixtrans);

this->hidden->pixtrans = 0;

/* Get the size required for the buffer */

_kernel_swi(ColourTrans_GenerateTable, &regs, &regs);

if (regs.r[4])

{

this->hidden->pixtrans = SDL_malloc(regs.r[4]);

regs.r[4] = (unsigned int)this->hidden->pixtrans;

/* Actually read the buffer */

_kernel_swi(ColourTrans_GenerateTable, &regs, &regs);

}

}

/* Plot the sprite in the given context */

void WIMP_PlotSprite(_THIS, int x, int y)

{

_kernel_swi_regs regs;

_kernel_oserror *err;

regs.r[0] = 52 + 512;

regs.r[1] = (unsigned int)this->hidden->bank[1];

regs.r[2] = (unsigned int)this->hidden->bank[1]+16;

regs.r[3] = x;

regs.r[4] = y;

regs.r[5] = 0|32; /* Overwrite screen and pixtrans contains wide colour entries */

regs.r[6] = 0; /* No scale factors i.e. 1:1 */

regs.r[7] = (int)this->hidden->pixtrans;

if ((err = _kernel_swi(OS_SpriteOp, &regs, &regs)) != 0)

{

int *p = (int *)this->hidden->pixtrans;

printf("OS_SpriteOp failed \n%s\n",err->errmess);

printf("pixtrans %d\n", (int)this->hidden->pixtrans);

printf("%x %x %x\n", p[0], p[1], p[2]);

}

}

/* Wimp mode has changes so update colour mapping and pixel sizes

of windows and the sprites they plot */

void WIMP_ModeChanged(_THIS)

{

int oldXeig = this->hidden->xeig;

int oldYeig = this->hidden->yeig;

WIMP_ReadModeInfo(this);

if (oldXeig == this->hidden->xeig && oldYeig == this->hidden->yeig)

{

/* Only need to update the palette */

WIMP_PaletteChanged(this);

} else

{

_kernel_swi_regs regs;

int window_state[9];

int extent[4];

int currWidth, currHeight;

int newWidth, newHeight;

/* Need to resize windows and update the palette */

WIMP_SetupPlotInfo(this);

window_state[0] = this->hidden->window_handle;

regs.r[1] = (unsigned int)window_state;

_kernel_swi(Wimp_GetWindowState, &regs, &regs);

currWidth = window_state[3] - window_state[1];

currHeight = window_state[4] - window_state[2];

newWidth = (currWidth >> oldXeig) << this->hidden->xeig;

newHeight = (currHeight >> oldYeig) << this->hidden->yeig;

/* Need to avoid extent getting too small for visible part

of window */

extent[0] = 0;

if (currHeight <= newHeight)

{

extent[1] = -newHeight;

} else

{

extent[1] = -currHeight;

}

if (currWidth <= newWidth)

{

extent[2] = newWidth;

} else

{

extent[2] = currWidth;

}

extent[3] = 0;

regs.r[0] = this->hidden->window_handle;

regs.r[1] = (int)extent;

_kernel_swi(Wimp_SetExtent, &regs, &regs);

/*TODO: May need to set flag to resize window on next open */

}

}

/* Palette has changed so update palettes used for windows sprites */

void WIMP_PaletteChanged(_THIS)

{

WIMP_SetupPlotInfo(this);

}