gfx.c
author peter1138
Sun, 01 Oct 2006 12:00:32 +0000
changeset 4694 c917a3ad0dd2
parent 4610 f264efbf7f4f
child 4819 8e62e6231890
permissions -rw-r--r--
(svn r6601) - Codechange: Support cargo subtypes in the refit window. The refit window has been altered to support resizing and scrolling. Note that the cargo subtype isn't yet passed for actual refitting yet. (Based on mart3p's patch)
/* $Id$ */

#include "stdafx.h"
#include "openttd.h"
#include "functions.h"
#include "macros.h"
#include "spritecache.h"
#include "strings.h"
#include "string.h"
#include "gfx.h"
#include "table/palettes.h"
#include "table/sprites.h"
#include "hal.h"
#include "variables.h"
#include "genworld.h"

#ifdef _DEBUG
bool _dbg_screen_rect;
#endif

Colour _cur_palette[256];
byte _stringwidth_table[FS_END][224];

static void GfxMainBlitter(const Sprite *sprite, int x, int y, int mode);

FontSize _cur_fontsize;
static FontSize _last_fontsize;
static Pixel _cursor_backup[64 * 64];
static Rect _invalid_rect;
static const byte *_color_remap_ptr;
static byte _string_colorremap[3];

#define DIRTY_BYTES_PER_LINE (MAX_SCREEN_WIDTH / 64)
static byte _dirty_blocks[DIRTY_BYTES_PER_LINE * MAX_SCREEN_HEIGHT / 8];



void memcpy_pitch(void *d, void *s, int w, int h, int spitch, int dpitch)
{
	byte *dp = (byte*)d;
	byte *sp = (byte*)s;

	assert(h >= 0);
	for (; h != 0; --h) {
		memcpy(dp, sp, w);
		dp += dpitch;
		sp += spitch;
	}
}


void GfxScroll(int left, int top, int width, int height, int xo, int yo)
{
	const Pixel *src;
	Pixel *dst;
	int p;
	int ht;

	if (xo == 0 && yo == 0) return;

	if (_cursor.visible) UndrawMouseCursor();
	UndrawTextMessage();

	p = _screen.pitch;

	if (yo > 0) {
		// Calculate pointers
		dst = _screen.dst_ptr + (top + height - 1) * p + left;
		src = dst - yo * p;

		// Decrease height and increase top
		top += yo;
		height -= yo;
		assert(height > 0);

		// Adjust left & width
		if (xo >= 0) {
			dst += xo;
			left += xo;
			width -= xo;
		} else {
			src -= xo;
			width += xo;
		}

		for (ht = height; ht > 0; --ht) {
			memcpy(dst, src, width);
			src -= p;
			dst -= p;
		}
	} else {
		// Calculate pointers
		dst = _screen.dst_ptr + top * p + left;
		src = dst - yo * p;

		// Decrese height. (yo is <=0).
		height += yo;
		assert(height > 0);

		// Adjust left & width
		if (xo >= 0) {
			dst += xo;
			left += xo;
			width -= xo;
		} else {
			src -= xo;
			width += xo;
		}

		// the y-displacement may be 0 therefore we have to use memmove,
		// because source and destination may overlap
		for (ht = height; ht > 0; --ht) {
			memmove(dst, src, width);
			src += p;
			dst += p;
		}
	}
	// This part of the screen is now dirty.
	_video_driver->make_dirty(left, top, width, height);
}


void GfxFillRect(int left, int top, int right, int bottom, int color)
{
	const DrawPixelInfo* dpi = _cur_dpi;
	Pixel *dst;
	const int otop = top;
	const int oleft = left;

	if (dpi->zoom != 0) return;
	if (left > right || top > bottom) return;
	if (right < dpi->left || left >= dpi->left + dpi->width) return;
	if (bottom < dpi->top || top >= dpi->top + dpi->height) return;

	if ( (left -= dpi->left) < 0) left = 0;
	right = right - dpi->left + 1;
	if (right > dpi->width) right = dpi->width;
	right -= left;
	assert(right > 0);

	if ( (top -= dpi->top) < 0) top = 0;
	bottom = bottom - dpi->top + 1;
	if (bottom > dpi->height) bottom = dpi->height;
	bottom -= top;
	assert(bottom > 0);

	dst = dpi->dst_ptr + top * dpi->pitch + left;

	if (!(color & PALETTE_MODIFIER_GREYOUT)) {
		if (!(color & USE_COLORTABLE)) {
			do {
				memset(dst, color, right);
				dst += dpi->pitch;
			} while (--bottom);
		} else {
			/* use colortable mode */
			const byte* ctab = GetNonSprite(color & COLORTABLE_MASK) + 1;

			do {
				int i;
				for (i = 0; i != right; i++) dst[i] = ctab[dst[i]];
				dst += dpi->pitch;
			} while (--bottom);
		}
	} else {
		byte bo = (oleft - left + dpi->left + otop - top + dpi->top) & 1;
		do {
			int i;
			for (i = (bo ^= 1); i < right; i += 2) dst[i] = (byte)color;
			dst += dpi->pitch;
		} while (--bottom > 0);
	}
}

static void GfxSetPixel(int x, int y, int color)
{
	const DrawPixelInfo* dpi = _cur_dpi;
	if ((x-=dpi->left) < 0 || x>=dpi->width || (y-=dpi->top)<0 || y>=dpi->height)
		return;
	dpi->dst_ptr[y * dpi->pitch + x] = color;
}

void GfxDrawLine(int x, int y, int x2, int y2, int color)
{
	int dy;
	int dx;
	int stepx;
	int stepy;
	int frac;

	// Check clipping first
	{
		DrawPixelInfo *dpi = _cur_dpi;
		int t;

		if (x < dpi->left && x2 < dpi->left) return;

		if (y < dpi->top && y2 < dpi->top) return;

		t = dpi->left + dpi->width;
		if (x > t && x2 > t) return;

		t = dpi->top + dpi->height;
		if (y > t && y2 > t) return;
	}

	dy = (y2 - y) * 2;
	if (dy < 0) {
		dy = -dy;
		stepy = -1;
	} else {
		stepy = 1;
	}

	dx = (x2 - x) * 2;
	if (dx < 0) {
		dx = -dx;
		stepx = -1;
	} else {
		stepx = 1;
	}

	GfxSetPixel(x, y, color);
	if (dx > dy) {
		frac = dy - (dx >> 1);
		while (x != x2) {
			if (frac >= 0) {
				y += stepy;
				frac -= dx;
			}
			x += stepx;
			frac += dy;
			GfxSetPixel(x, y, color);
		}
	} else {
		frac = dx - (dy >> 1);
		while (y != y2) {
			if (frac >= 0) {
				x += stepx;
				frac -= dy;
			}
			y += stepy;
			frac += dx;
			GfxSetPixel(x, y, color);
		}
	}
}


static inline SpriteID GetFontBase(FontSize size)
{
	switch (size) {
		default: NOT_REACHED();
		case FS_NORMAL: return SPR_ASCII_SPACE;
		case FS_SMALL:  return SPR_ASCII_SPACE_SMALL;
		case FS_LARGE:  return SPR_ASCII_SPACE_BIG;
	}
}


// ASSIGNMENT OF ASCII LETTERS < 32
// 0 - end of string
// 1 - SETX <BYTE>
// 2 - SETXY <BYTE> <BYTE>
// 3-7 -
// 8 - TINYFONT
// 9 - BIGFONT
// 10 - newline
// 11-14 -
// 15-31 - 17 colors


enum {
	ASCII_SETX       =  1,
	ASCII_SETXY      =  2,

	ASCII_TINYFONT   =  8,
	ASCII_BIGFONT    =  9,
	ASCII_NL         = 10,

	ASCII_COLORSTART = 15,
};

/** Truncate a given string to a maximum width if neccessary.
 * If the string is truncated, add three dots ('...') to show this.
 * @param *dest string that is checked and possibly truncated
 * @param maxw maximum width in pixels of the string
 * @return new width of (truncated) string */
static int TruncateString(char *str, int maxw)
{
	int w = 0;
	FontSize size = _cur_fontsize;
	int ddd, ddd_w;

	byte c;
	char *ddd_pos;

	ddd_w = ddd = GetCharacterWidth(size, '.') * 3;

	for (ddd_pos = str; (c = *str++) != '\0'; ) {
		if (c >= ASCII_LETTERSTART) {
			w += GetCharacterWidth(size, c);

			if (w >= maxw) {
				// string got too big... insert dotdotdot
				ddd_pos[0] = ddd_pos[1] = ddd_pos[2] = '.';
				ddd_pos[3] = 0;
				return ddd_w;
			}
		} else {
			if (c == ASCII_SETX) str++;
			else if (c == ASCII_SETXY) str += 2;
			else if (c == ASCII_TINYFONT) {
				size = FS_SMALL;
				ddd = GetCharacterWidth(size, '.') * 3;
			} else if (c == ASCII_BIGFONT) {
				size = FS_LARGE;
				ddd = GetCharacterWidth(size, '.') * 3;
			}
		}

		// Remember the last position where three dots fit.
		if (w + ddd < maxw) {
			ddd_w = w + ddd;
			ddd_pos = str;
		}
	}

	return w;
}

static inline int TruncateStringID(StringID src, char *dest, int maxw)
{
	GetString(dest, src);
	return TruncateString(dest, maxw);
}

/* returns right coordinate */
int DrawString(int x, int y, StringID str, uint16 color)
{
	char buffer[512];

	GetString(buffer, str);
	return DoDrawString(buffer, x, y, color);
}

int DrawStringTruncated(int x, int y, StringID str, uint16 color, uint maxw)
{
	char buffer[512];
	TruncateStringID(str, buffer, maxw);
	return DoDrawString(buffer, x, y, color);
}


int DrawStringRightAligned(int x, int y, StringID str, uint16 color)
{
	char buffer[512];
	int w;

	GetString(buffer, str);
	w = GetStringBoundingBox(buffer).width;
	DoDrawString(buffer, x - w, y, color);

	return w;
}

void DrawStringRightAlignedTruncated(int x, int y, StringID str, uint16 color, uint maxw)
{
	char buffer[512];

	TruncateStringID(str, buffer, maxw);
	DoDrawString(buffer, x - GetStringBoundingBox(buffer).width, y, color);
}

void DrawStringRightAlignedUnderline(int x, int y, StringID str, uint16 color)
{
	int w = DrawStringRightAligned(x, y, str, color);
	GfxFillRect(x - w, y + 10, x, y + 10, _string_colorremap[1]);
}


int DrawStringCentered(int x, int y, StringID str, uint16 color)
{
	char buffer[512];
	int w;

	GetString(buffer, str);

	w = GetStringBoundingBox(buffer).width;
	DoDrawString(buffer, x - w / 2, y, color);

	return w;
}

int DrawStringCenteredTruncated(int xl, int xr, int y, StringID str, uint16 color)
{
	char buffer[512];
	int w = TruncateStringID(str, buffer, xr - xl);
	return DoDrawString(buffer, (xl + xr - w) / 2, y, color);
}

int DoDrawStringCentered(int x, int y, const char *str, uint16 color)
{
	int w = GetStringBoundingBox(str).width;
	DoDrawString(str, x - w / 2, y, color);
	return w;
}

void DrawStringCenterUnderline(int x, int y, StringID str, uint16 color)
{
	int w = DrawStringCentered(x, y, str, color);
	GfxFillRect(x - (w >> 1), y + 10, x - (w >> 1) + w, y + 10, _string_colorremap[1]);
}

void DrawStringCenterUnderlineTruncated(int xl, int xr, int y, StringID str, uint16 color)
{
	int w = DrawStringCenteredTruncated(xl, xr, y, str, color);
	GfxFillRect((xl + xr - w) / 2, y + 10, (xl + xr + w) / 2, y + 10, _string_colorremap[1]);
}

static uint32 FormatStringLinebreaks(char *str, int maxw)
{
	int num = 0;
	FontSize size = _cur_fontsize;
	int w;
	char *last_space;
	byte c;

	for (;;) {
		w = 0;
		last_space = NULL;

		for (;;) {
			c = *str++;
			if (c == ASCII_LETTERSTART) last_space = str;

			if (c >= ASCII_LETTERSTART) {
				w += GetCharacterWidth(size, c);
				if (w > maxw) {
					str = last_space;
					if (str == NULL)
						return num + (size << 16);
					break;
				}
			} else {
				if (c == 0) return num + (size << 16);
				if (c == ASCII_NL) break;

				if (c == ASCII_SETX) str++;
				else if (c == ASCII_SETXY) str += 2;
				else if (c == ASCII_TINYFONT) size = FS_SMALL;
				else if (c == ASCII_BIGFONT) size = FS_LARGE;
			}
		}

		num++;
		str[-1] = '\0';
	}
}

void DrawStringMultiCenter(int x, int y, StringID str, int maxw)
{
	char buffer[512];
	uint32 tmp;
	int num, w, mt;
	const char *src;
	byte c;

	GetString(buffer, str);

	tmp = FormatStringLinebreaks(buffer, maxw);
	num = GB(tmp, 0, 16);

	mt = GetCharacterHeight(GB(tmp, 16, 16));

	y -= (mt >> 1) * num;

	src = buffer;

	for (;;) {
		w = GetStringBoundingBox(src).width;
		DoDrawString(src, x - (w>>1), y, 0xFE);
		_cur_fontsize = _last_fontsize;

		for (;;) {
			c = *src++;
			if (c == 0) {
				y += mt;
				if (--num < 0) {
					_cur_fontsize = FS_NORMAL;
					return;
				}
				break;
			} else if (c == ASCII_SETX) {
				src++;
			} else if (c == ASCII_SETXY) {
				src+=2;
			}
		}
	}
}

void DrawStringMultiLine(int x, int y, StringID str, int maxw)
{
	char buffer[512];
	uint32 tmp;
	int num, mt;
	const char *src;
	byte c;

	GetString(buffer, str);

	tmp = FormatStringLinebreaks(buffer, maxw);
	num = GB(tmp, 0, 16);

	mt = GetCharacterHeight(GB(tmp, 16, 16));

	src = buffer;

	for (;;) {
		DoDrawString(src, x, y, 0xFE);
		_cur_fontsize = _last_fontsize;

		for (;;) {
			c = *src++;
			if (c == 0) {
				y += mt;
				if (--num < 0) {
					_cur_fontsize = FS_NORMAL;
					return;
				}
				break;
			} else if (c == ASCII_SETX) {
				src++;
			} else if (c == ASCII_SETXY) {
				src+=2;
			}
		}
	}
}

/** Return the string dimension in pixels. The height and width are returned
 * in a single BoundingRect value. TINYFONT, BIGFONT modifiers are only
 * supported as the first character of the string. The returned dimensions
 * are therefore a rough estimation correct for all the current strings
 * but not every possible combination
 * @param str string to calculate pixel-width
 * @return string width and height in pixels */
BoundingRect GetStringBoundingBox(const char *str)
{
	FontSize size = _cur_fontsize;
	BoundingRect br;
	int max_width;
	byte c;

	br.width = br.height = max_width = 0;
	for (c = *str; c != '\0'; c = *(++str)) {
		if (c >= ASCII_LETTERSTART) {
			br.width += GetCharacterWidth(size, c);
		} else {
			switch (c) {
				case ASCII_SETX: br.width += (byte)*str++; break;
				case ASCII_SETXY:
					br.width += (byte)*str++;
					br.height += (byte)*str++;
					break;
				case ASCII_TINYFONT: size = FS_SMALL; break;
				case ASCII_BIGFONT:  size = FS_LARGE; break;
				case ASCII_NL:
					br.height += GetCharacterHeight(size);
					if (br.width > max_width) max_width = br.width;
					br.width = 0;
					break;
			}
		}
	}
	br.height += GetCharacterHeight(size);

	br.width  = max(br.width, max_width);
	return br;
}


int DoDrawString(const char *string, int x, int y, uint16 real_color)
{
	DrawPixelInfo *dpi = _cur_dpi;
	FontSize size = _cur_fontsize;
	byte c;
	byte color;
	int xo = x, yo = y;

	color = real_color & 0xFF;

	if (color != 0xFE) {
		if (x >= dpi->left + dpi->width ||
				x + _screen.width*2 <= dpi->left ||
				y >= dpi->top + dpi->height ||
				y + _screen.height <= dpi->top)
					return x;

		if (color != 0xFF) {
switch_color:;
			if (real_color & IS_PALETTE_COLOR) {
				_string_colorremap[1] = color;
				_string_colorremap[2] = 215;
			} else {
				_string_colorremap[1] = _string_colormap[color].text;
				_string_colorremap[2] = _string_colormap[color].shadow;
			}
			_color_remap_ptr = _string_colorremap;
		}
	}

check_bounds:
	if (y + 19 <= dpi->top || dpi->top + dpi->height <= y) {
skip_char:;
		for (;;) {
			c = *string++;
			if (c < ASCII_LETTERSTART) goto skip_cont;
		}
	}

	for (;;) {
		c = *string++;
skip_cont:;
		if (c == 0) {
			_last_fontsize = size;
			return x;
		}
		if (c >= ASCII_LETTERSTART) {
			if (x >= dpi->left + dpi->width) goto skip_char;
			if (x + 26 >= dpi->left) {
				GfxMainBlitter(GetSprite(GetFontBase(size) + c - ASCII_LETTERSTART), x, y, 1);
			}
			x += GetCharacterWidth(size, c);
		} else if (c == ASCII_NL) { // newline = {}
			x = xo;
			y += GetCharacterHeight(size);
			goto check_bounds;
		} else if (c >= ASCII_COLORSTART) { // change color?
			color = (byte)(c - ASCII_COLORSTART);
			goto switch_color;
		} else if (c == ASCII_SETX) { // {SETX}
			x = xo + (byte)*string++;
		} else if (c == ASCII_SETXY) {// {SETXY}
			x = xo + (byte)*string++;
			y = yo + (byte)*string++;
		} else if (c == ASCII_TINYFONT) { // {TINYFONT}
			size = FS_SMALL;
		} else if (c == ASCII_BIGFONT) { // {BIGFONT}
			size = FS_LARGE;
		} else {
			printf("Unknown string command character %d\n", c);
		}
	}
}

int DoDrawStringTruncated(const char *str, int x, int y, uint16 color, uint maxw)
{
	char buffer[512];
	ttd_strlcpy(buffer, str, sizeof(buffer));
	TruncateString(buffer, maxw);
	return DoDrawString(buffer, x, y, color);
}

void DrawSprite(uint32 img, int x, int y)
{
	if (img & PALETTE_MODIFIER_COLOR) {
		_color_remap_ptr = GetNonSprite(GB(img, PALETTE_SPRITE_START, PALETTE_SPRITE_WIDTH)) + 1;
		GfxMainBlitter(GetSprite(img & SPRITE_MASK), x, y, 1);
	} else if (img & PALETTE_MODIFIER_TRANSPARENT) {
		_color_remap_ptr = GetNonSprite(GB(img, PALETTE_SPRITE_START, PALETTE_SPRITE_WIDTH)) + 1;
		GfxMainBlitter(GetSprite(img & SPRITE_MASK), x, y, 2);
	} else {
		GfxMainBlitter(GetSprite(img & SPRITE_MASK), x, y, 0);
	}
}

typedef struct BlitterParams {
	int start_x, start_y;
	const byte *sprite;
	Pixel *dst;
	int mode;
	int width, height;
	int width_org;
	int pitch;
} BlitterParams;

static void GfxBlitTileZoomIn(BlitterParams *bp)
{
	const byte *src_o = bp->sprite;
	const byte *src;
	int num, skip;
	byte done;
	Pixel *dst;
	const byte *ctab;

	src_o += ReadLE16Aligned(src_o + bp->start_y * 2);
	switch (bp->mode) {
		case 1:
			do {
				do {
					done = src_o[0];
					num = done & 0x7F;
					skip = src_o[1];
					src = src_o + 2;
					src_o += num + 2;

					dst = bp->dst;

					if ( (skip -= bp->start_x) > 0) {
						dst += skip;
					} else {
						src -= skip;
						num += skip;
						if (num <= 0) continue;
						skip = 0;
					}

					skip = skip + num - bp->width;
					if (skip > 0) {
						num -= skip;
						if (num <= 0) continue;
					}

					ctab = _color_remap_ptr;

					for (; num >= 4; num -=4) {
						dst[3] = ctab[src[3]];
						dst[2] = ctab[src[2]];
						dst[1] = ctab[src[1]];
						dst[0] = ctab[src[0]];
						dst += 4;
						src += 4;
					}
					for (; num != 0; num--) *dst++ = ctab[*src++];
				} while (!(done & 0x80));

				bp->dst += bp->pitch;
			} while (--bp->height != 0);
			break;

		case 2:
			do {
				do {
					done = src_o[0];
					num = done & 0x7F;
					skip = src_o[1];
					src_o += num + 2;

					dst = bp->dst;

					if ( (skip -= bp->start_x) > 0) {
						dst += skip;
					} else {
						num += skip;
						if (num <= 0) continue;
						skip = 0;
					}

					skip = skip + num - bp->width;
					if (skip > 0) {
						num -= skip;
						if (num <= 0) continue;
					}

					ctab = _color_remap_ptr;
					for (; num != 0; num--) {
						*dst = ctab[*dst];
						dst++;
					}
				} while (!(done & 0x80));

				bp->dst += bp->pitch;
			} while (--bp->height != 0);
			break;

		default:
			do {
				do {
					done = src_o[0];
					num = done & 0x7F;
					skip = src_o[1];
					src = src_o + 2;
					src_o += num + 2;

					dst = bp->dst;

					if ( (skip -= bp->start_x) > 0) {
						dst += skip;
					} else {
						src -= skip;
						num += skip;
						if (num <= 0) continue;
						skip = 0;
					}

					skip = skip + num - bp->width;
					if (skip > 0) {
						num -= skip;
						if (num <= 0) continue;
					}
#if defined(_WIN32)
					if (num & 1) *dst++ = *src++;
					if (num & 2) { *(uint16*)dst = *(uint16*)src; dst += 2; src += 2; }
					if (num >>= 2) {
						do {
							*(uint32*)dst = *(uint32*)src;
							dst += 4;
							src += 4;
						} while (--num != 0);
					}
#else
					memcpy(dst, src, num);
#endif
				} while (!(done & 0x80));

				bp->dst += bp->pitch;
			} while (--bp->height != 0);
			break;
	}
}

static void GfxBlitZoomInUncomp(BlitterParams *bp)
{
	const byte *src = bp->sprite;
	Pixel *dst = bp->dst;
	int height = bp->height;
	int width = bp->width;
	int i;

	assert(height > 0);
	assert(width > 0);

	switch (bp->mode) {
		case 1: {
			const byte *ctab = _color_remap_ptr;

			do {
				for (i = 0; i != width; i++) {
					byte b = ctab[src[i]];

					if (b != 0) dst[i] = b;
				}
				src += bp->width_org;
				dst += bp->pitch;
			} while (--height != 0);
			break;
		}

		case 2: {
			const byte *ctab = _color_remap_ptr;

			do {
				for (i = 0; i != width; i++)
					if (src[i] != 0) dst[i] = ctab[dst[i]];
				src += bp->width_org;
				dst += bp->pitch;
			} while (--height != 0);
			break;
		}

		default:
			do {
				int n = width;

				for (; n >= 4; n -= 4) {
					if (src[0] != 0) dst[0] = src[0];
					if (src[1] != 0) dst[1] = src[1];
					if (src[2] != 0) dst[2] = src[2];
					if (src[3] != 0) dst[3] = src[3];

					dst += 4;
					src += 4;
				}

				for (; n != 0; n--) {
					if (src[0] != 0) dst[0] = src[0];
					src++;
					dst++;
				}

				src += bp->width_org - width;
				dst += bp->pitch - width;
			} while (--height != 0);
			break;
	}
}

static void GfxBlitTileZoomMedium(BlitterParams *bp)
{
	const byte *src_o = bp->sprite;
	const byte *src;
	int num, skip;
	byte done;
	Pixel *dst;
	const byte *ctab;

	src_o += ReadLE16Aligned(src_o + bp->start_y * 2);
	switch (bp->mode) {
		case 1:
			do {
				do {
					done = src_o[0];
					num = done & 0x7F;
					skip = src_o[1];
					src = src_o + 2;
					src_o += num + 2;

					dst = bp->dst;

					if (skip & 1) {
						skip++;
						src++;
						if (--num == 0) continue;
					}

					if ( (skip -= bp->start_x) > 0) {
						dst += skip >> 1;
					} else {
						src -= skip;
						num += skip;
						if (num <= 0) continue;
						skip = 0;
					}

					skip = skip + num - bp->width;
					if (skip > 0) {
						num -= skip;
						if (num <= 0) continue;
					}

					ctab = _color_remap_ptr;
					num = (num + 1) >> 1;
					for (; num != 0; num--) {
							*dst = ctab[*src];
							dst++;
							src += 2;
					}
				} while (!(done & 0x80));
				bp->dst += bp->pitch;
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
			} while (--bp->height != 0);
			break;

		case 2:
			do {
				do {
					done = src_o[0];
					num = done & 0x7F;
					skip = src_o[1];
					src_o += num + 2;

					dst = bp->dst;

					if (skip & 1) {
						skip++;
						if (--num == 0) continue;
					}

					if ( (skip -= bp->start_x) > 0) {
						dst += skip >> 1;
					} else {
						num += skip;
						if (num <= 0) continue;
						skip = 0;
					}

					skip = skip + num - bp->width;
					if (skip > 0) {
						num -= skip;
						if (num <= 0) continue;
					}

					ctab = _color_remap_ptr;
					num = (num + 1) >> 1;
					for (; num != 0; num--) {
							*dst = ctab[*dst];
							dst++;
					}
				} while (!(done & 0x80));
				bp->dst += bp->pitch;
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
			} while (--bp->height != 0);
			break;

		default:
			do {
				do {
					done = src_o[0];
					num = done & 0x7F;
					skip = src_o[1];
					src = src_o + 2;
					src_o += num + 2;

					dst = bp->dst;

					if (skip & 1) {
						skip++;
						src++;
						if (--num == 0) continue;
					}

					if ( (skip -= bp->start_x) > 0) {
						dst += skip >> 1;
					} else {
						src -= skip;
						num += skip;
						if (num <= 0) continue;
						skip = 0;
					}

					skip = skip + num - bp->width;
					if (skip > 0) {
						num -= skip;
						if (num <= 0) continue;
					}

					num = (num + 1) >> 1;

					for (; num != 0; num--) {
							*dst = *src;
							dst++;
							src += 2;
					}

				} while (!(done & 0x80));

				bp->dst += bp->pitch;
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
			} while (--bp->height != 0);
			break;
	}
}

static void GfxBlitZoomMediumUncomp(BlitterParams *bp)
{
	const byte *src = bp->sprite;
	Pixel *dst = bp->dst;
	int height = bp->height;
	int width = bp->width;
	int i;

	assert(height > 0);
	assert(width > 0);

	switch (bp->mode) {
		case 1: {
			const byte *ctab = _color_remap_ptr;

			for (height >>= 1; height != 0; height--) {
				for (i = 0; i != width >> 1; i++) {
					byte b = ctab[src[i * 2]];

					if (b != 0) dst[i] = b;
				}
				src += bp->width_org * 2;
				dst += bp->pitch;
			}
			break;
		}

		case 2: {
			const byte *ctab = _color_remap_ptr;

			for (height >>= 1; height != 0; height--) {
				for (i = 0; i != width >> 1; i++)
					if (src[i * 2] != 0) dst[i] = ctab[dst[i]];
				src += bp->width_org * 2;
				dst += bp->pitch;
			}
			break;
		}

		default:
			for (height >>= 1; height != 0; height--) {
				for (i = 0; i != width >> 1; i++)
					if (src[i * 2] != 0) dst[i] = src[i * 2];
				src += bp->width_org * 2;
				dst += bp->pitch;
			}
			break;
	}
}

static void GfxBlitTileZoomOut(BlitterParams *bp)
{
	const byte *src_o = bp->sprite;
	const byte *src;
	int num, skip;
	byte done;
	Pixel *dst;
	const byte *ctab;

	src_o += ReadLE16Aligned(src_o + bp->start_y * 2);
	switch (bp->mode) {
		case 1:
			for (;;) {
				do {
					done = src_o[0];
					num = done & 0x7F;
					skip = src_o[1];
					src = src_o + 2;
					src_o += num + 2;

					dst = bp->dst;

					if (skip & 1) {
						skip++;
						src++;
						if (--num == 0) continue;
					}

					if (skip & 2) {
						skip += 2;
						src += 2;
						num -= 2;
						if (num <= 0) continue;
					}

					if ( (skip -= bp->start_x) > 0) {
						dst += skip >> 2;
					} else {
						src -= skip;
						num += skip;
						if (num <= 0) continue;
						skip = 0;
					}

					skip = skip + num - bp->width;
					if (skip > 0) {
						num -= skip;
						if (num <= 0) continue;
					}

					ctab = _color_remap_ptr;
					num = (num + 3) >> 2;
					for (; num != 0; num--) {
							*dst = ctab[*src];
							dst++;
							src += 4;
					}
				} while (!(done & 0x80));
				bp->dst += bp->pitch;
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
				if (--bp->height == 0) return;
			}
			break;

		case  2:
			for (;;) {
				do {
					done = src_o[0];
					num = done & 0x7F;
					skip = src_o[1];
					src_o += num + 2;

					dst = bp->dst;

					if (skip & 1) {
						skip++;
						if (--num == 0) continue;
					}

					if (skip & 2) {
						skip += 2;
						num -= 2;
						if (num <= 0) continue;
					}

					if ( (skip -= bp->start_x) > 0) {
						dst += skip >> 2;
					} else {
						num += skip;
						if (num <= 0) continue;
						skip = 0;
					}

					skip = skip + num - bp->width;
					if (skip > 0) {
						num -= skip;
						if (num <= 0) continue;
					}

					ctab = _color_remap_ptr;
					num = (num + 3) >> 2;
					for (; num != 0; num--) {
							*dst = ctab[*dst];
							dst++;
					}

				} while (!(done & 0x80));
				bp->dst += bp->pitch;
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
				if (--bp->height == 0) return;
			}
			break;

		default:
			for (;;) {
				do {
					done = src_o[0];
					num = done & 0x7F;
					skip = src_o[1];
					src = src_o + 2;
					src_o += num + 2;

					dst = bp->dst;

					if (skip & 1) {
						skip++;
						src++;
						if (--num == 0) continue;
					}

					if (skip & 2) {
						skip += 2;
						src += 2;
						num -= 2;
						if (num <= 0) continue;
					}

					if ( (skip -= bp->start_x) > 0) {
						dst += skip >> 2;
					} else {
						src -= skip;
						num += skip;
						if (num <= 0) continue;
						skip = 0;
					}

					skip = skip + num - bp->width;
					if (skip > 0) {
						num -= skip;
						if (num <= 0) continue;
					}

					num = (num + 3) >> 2;

					for (; num != 0; num--) {
							*dst = *src;
							dst++;
							src += 4;
					}
				} while (!(done & 0x80));

				bp->dst += bp->pitch;
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
				if (--bp->height == 0) return;

				do {
					done = src_o[0];
					src_o += (done & 0x7F) + 2;
				} while (!(done & 0x80));
				if (--bp->height == 0) return;
			}
			break;
	}
}

static void GfxBlitZoomOutUncomp(BlitterParams *bp)
{
	const byte *src = bp->sprite;
	Pixel *dst = bp->dst;
	int height = bp->height;
	int width = bp->width;
	int i;

	assert(height > 0);
	assert(width > 0);

	switch (bp->mode) {
		case 1: {
			const byte *ctab = _color_remap_ptr;

			for (height >>= 2; height != 0; height--) {
				for (i = 0; i != width >> 2; i++) {
					byte b = ctab[src[i * 4]];

					if (b != 0) dst[i] = b;
				}
				src += bp->width_org * 4;
				dst += bp->pitch;
			}
			break;
		}

		case 2: {
			const byte *ctab = _color_remap_ptr;

			for (height >>= 2; height != 0; height--) {
				for (i = 0; i != width >> 2; i++)
					if (src[i * 4] != 0) dst[i] = ctab[dst[i]];
				src += bp->width_org * 4;
				dst += bp->pitch;
			}
			break;
		}

		default:
			for (height >>= 2; height != 0; height--) {
				for (i = 0; i != width >> 2; i++)
					if (src[i * 4] != 0) dst[i] = src[i * 4];
				src += bp->width_org * 4;
				dst += bp->pitch;
			}
			break;
	}
}


static void GfxMainBlitter(const Sprite *sprite, int x, int y, int mode)
{
	const DrawPixelInfo *dpi = _cur_dpi;
	int start_x, start_y;
	BlitterParams bp;
	int zoom_mask = ~((1 << dpi->zoom) - 1);

	/* decode sprite header */
	x += sprite->x_offs;
	y += sprite->y_offs;
	bp.width_org = bp.width = sprite->width;
	bp.height = sprite->height;
	bp.sprite = sprite->data;
	bp.dst = dpi->dst_ptr;
	bp.mode = mode;
	bp.pitch = dpi->pitch;

	assert(bp.height > 0);
	assert(bp.width > 0);

	if (sprite->info & 8) {
		/* tile blit */
		start_y = 0;

		if (dpi->zoom > 0) {
			start_y += bp.height & ~zoom_mask;
			bp.height &= zoom_mask;
			if (bp.height == 0) return;
			y &= zoom_mask;
		}

		if ( (y -= dpi->top) < 0) {
			bp.height += y;
			if (bp.height <= 0) return;
			start_y -= y;
			y = 0;
		} else {
			bp.dst += bp.pitch * (y >> dpi->zoom);
		}
		bp.start_y = start_y;

		if ( (y = y + bp.height - dpi->height) > 0) {
			bp.height -= y;
			if (bp.height <= 0) return;
		}

		start_x = 0;
		x &= zoom_mask;
		if ( (x -= dpi->left) < 0) {
			bp.width += x;
			if (bp.width <= 0) return;
			start_x -= x;
			x = 0;
		}
		bp.start_x = start_x;
		bp.dst += x >> dpi->zoom;

		if ( (x = x + bp.width - dpi->width) > 0) {
			bp.width -= x;
			if (bp.width <= 0) return;
		}

		switch (dpi->zoom) {
			default: NOT_REACHED();
			case 0: GfxBlitTileZoomIn(&bp);     break;
			case 1: GfxBlitTileZoomMedium(&bp); break;
			case 2: GfxBlitTileZoomOut(&bp);    break;
		}
	} else {
		bp.sprite += bp.width * (bp.height & ~zoom_mask);
		bp.height &= zoom_mask;
		if (bp.height == 0) return;

		y &= zoom_mask;

		if ( (y -= dpi->top) < 0) {
			bp.height += y;
			if (bp.height <= 0) return;
			bp.sprite -= bp.width * y;
			y = 0;
		} else {
			bp.dst += bp.pitch * (y >> dpi->zoom);
		}

		if (bp.height > dpi->height - y) {
			bp.height = dpi->height - y;
			if (bp.height <= 0) return;
		}

		x &= zoom_mask;

		if ( (x -= dpi->left) < 0) {
			bp.width += x;
			if (bp.width <= 0) return;
			bp.sprite -= x;
			x = 0;
		}
		bp.dst += x >> dpi->zoom;

		if (bp.width > dpi->width - x) {
			bp.width = dpi->width - x;
			if (bp.width <= 0) return;
		}

		switch (dpi->zoom) {
			default: NOT_REACHED();
			case 0: GfxBlitZoomInUncomp(&bp);     break;
			case 1: GfxBlitZoomMediumUncomp(&bp); break;
			case 2: GfxBlitZoomOutUncomp(&bp);    break;
		}
	}
}

void DoPaletteAnimations(void);

void GfxInitPalettes(void)
{
	memcpy(_cur_palette, _palettes[_use_dos_palette ? 1 : 0], sizeof(_cur_palette));

	_pal_first_dirty = 0;
	_pal_last_dirty = 255;
	DoPaletteAnimations();
}

#define EXTR(p, q) (((uint16)(_timer_counter * (p)) * (q)) >> 16)
#define EXTR2(p, q) (((uint16)(~_timer_counter * (p)) * (q)) >> 16)

void DoPaletteAnimations(void)
{
	const Colour *s;
	Colour *d;
	/* Amount of colors to be rotated.
	 * A few more for the DOS palette, because the water colors are
	 * 245-254 for DOS and 217-226 for Windows.  */
	const ExtraPaletteValues *ev = &_extra_palette_values;
	int c = _use_dos_palette ? 38 : 28;
	Colour old_val[38]; // max(38, 28)
	uint i;
	uint j;

	d = &_cur_palette[217];
	memcpy(old_val, d, c * sizeof(*old_val));

	// Dark blue water
	s = (_opt.landscape == LT_CANDY) ? ev->ac : ev->a;
	j = EXTR(320, 5);
	for (i = 0; i != 5; i++) {
		*d++ = s[j];
		j++;
		if (j == 5) j = 0;
	}

	// Glittery water
	s = (_opt.landscape == LT_CANDY) ? ev->bc : ev->b;
	j = EXTR(128, 15);
	for (i = 0; i != 5; i++) {
		*d++ = s[j];
		j += 3;
		if (j >= 15) j -= 15;
	}

	s = ev->e;
	j = EXTR2(512, 5);
	for (i = 0; i != 5; i++) {
		*d++ = s[j];
		j++;
		if (j == 5) j = 0;
	}

	// Oil refinery fire animation
	s = ev->oil_ref;
	j = EXTR2(512, 7);
	for (i = 0; i != 7; i++) {
		*d++ = s[j];
		j++;
		if (j == 7) j = 0;
	}

	// Radio tower blinking
	{
		byte i = (_timer_counter >> 1) & 0x7F;
		byte v;

		(v = 255, i < 0x3f) ||
		(v = 128, i < 0x4A || i >= 0x75) ||
		(v = 20);
		d->r = v;
		d->g = 0;
		d->b = 0;
		d++;

		i ^= 0x40;
		(v = 255, i < 0x3f) ||
		(v = 128, i < 0x4A || i >= 0x75) ||
		(v = 20);
		d->r = v;
		d->g = 0;
		d->b = 0;
		d++;
	}

	// Handle lighthouse and stadium animation
	s = ev->lighthouse;
	j = EXTR(256, 4);
	for (i = 0; i != 4; i++) {
		*d++ = s[j];
		j++;
		if (j == 4) j = 0;
	}

	// Animate water for old DOS graphics
	if (_use_dos_palette) {
		// Dark blue water DOS
		s = (_opt.landscape == LT_CANDY) ? ev->ac : ev->a;
		j = EXTR(320, 5);
		for (i = 0; i != 5; i++) {
			*d++ = s[j];
			j++;
			if (j == 5) j = 0;
		}

		// Glittery water DOS
		s = (_opt.landscape == LT_CANDY) ? ev->bc : ev->b;
		j = EXTR(128, 15);
		for (i = 0; i != 5; i++) {
			*d++ = s[j];
			j += 3;
			if (j >= 15) j -= 15;
		}
	}

	if (memcmp(old_val, &_cur_palette[217], c * sizeof(*old_val)) != 0) {
		if (_pal_first_dirty > 217) _pal_first_dirty = 217;
		if (_pal_last_dirty < 217 + c) _pal_last_dirty = 217 + c;
	}
}


void LoadStringWidthTable(void)
{
	SpriteID base;
	uint i;

	/* Normal font */
	base = GetFontBase(FS_NORMAL);
	for (i = 0; i != 224; i++) {
		_stringwidth_table[FS_NORMAL][i] = SpriteExists(base + i) ? GetSprite(base + i)->width : 0;
	}

	/* Small font */
	base = GetFontBase(FS_SMALL);
	for (i = 0; i != 224; i++) {
		_stringwidth_table[FS_SMALL][i] = SpriteExists(base + i) ? GetSprite(base + i)->width + 1 : 0;
	}

	/* Large font */
	base = GetFontBase(FS_LARGE);
	for (i = 0; i != 224; i++) {
		_stringwidth_table[FS_LARGE][i] = SpriteExists(base + i) ? GetSprite(base + i)->width + 1 : 0;
	}
}

void ScreenSizeChanged(void)
{
	// check the dirty rect
	if (_invalid_rect.right >= _screen.width) _invalid_rect.right = _screen.width;
	if (_invalid_rect.bottom >= _screen.height) _invalid_rect.bottom = _screen.height;

	// screen size changed and the old bitmap is invalid now, so we don't want to undraw it
	_cursor.visible = false;
}

void UndrawMouseCursor(void)
{
	if (_cursor.visible) {
		_cursor.visible = false;
		memcpy_pitch(
			_screen.dst_ptr + _cursor.draw_pos.x + _cursor.draw_pos.y * _screen.pitch,
			_cursor_backup,
			_cursor.draw_size.x, _cursor.draw_size.y, _cursor.draw_size.x, _screen.pitch);

		_video_driver->make_dirty(_cursor.draw_pos.x, _cursor.draw_pos.y, _cursor.draw_size.x, _cursor.draw_size.y);
	}
}

void DrawMouseCursor(void)
{
	int x;
	int y;
	int w;
	int h;

	/* Redraw mouse cursor but only when it's inside the window */
	if (!_cursor.in_window) return;

	// Don't draw the mouse cursor if it's already drawn
	if (_cursor.visible) {
		if (!_cursor.dirty) return;
		UndrawMouseCursor();
	}

	w = _cursor.size.x;
	x = _cursor.pos.x + _cursor.offs.x;
	if (x < 0) {
		w += x;
		x = 0;
	}
	if (w > _screen.width - x) w = _screen.width - x;
	if (w <= 0) return;
	_cursor.draw_pos.x = x;
	_cursor.draw_size.x = w;

	h = _cursor.size.y;
	y = _cursor.pos.y + _cursor.offs.y;
	if (y < 0) {
		h += y;
		y = 0;
	}
	if (h > _screen.height - y) h = _screen.height - y;
	if (h <= 0) return;
	_cursor.draw_pos.y = y;
	_cursor.draw_size.y = h;

	assert(w * h < (int)sizeof(_cursor_backup));

	// Make backup of stuff below cursor
	memcpy_pitch(
		_cursor_backup,
		_screen.dst_ptr + _cursor.draw_pos.x + _cursor.draw_pos.y * _screen.pitch,
		_cursor.draw_size.x, _cursor.draw_size.y, _screen.pitch, _cursor.draw_size.x);

	// Draw cursor on screen
	_cur_dpi = &_screen;
	DrawSprite(_cursor.sprite, _cursor.pos.x, _cursor.pos.y);

	_video_driver->make_dirty(_cursor.draw_pos.x, _cursor.draw_pos.y, _cursor.draw_size.x, _cursor.draw_size.y);

	_cursor.visible = true;
	_cursor.dirty = false;
}

#if defined(_DEBUG)
static void DbgScreenRect(int left, int top, int right, int bottom)
{
	DrawPixelInfo dp;
	DrawPixelInfo *old;

	old = _cur_dpi;
	_cur_dpi = &dp;
	dp = _screen;
	GfxFillRect(left, top, right - 1, bottom - 1, rand() & 255);
	_cur_dpi = old;
}
#endif

void RedrawScreenRect(int left, int top, int right, int bottom)
{
	assert(right <= _screen.width && bottom <= _screen.height);
	if (_cursor.visible) {
		if (right > _cursor.draw_pos.x &&
				left < _cursor.draw_pos.x + _cursor.draw_size.x &&
				bottom > _cursor.draw_pos.y &&
				top < _cursor.draw_pos.y + _cursor.draw_size.y) {
			UndrawMouseCursor();
		}
	}
	UndrawTextMessage();

#if defined(_DEBUG)
	if (_dbg_screen_rect)
		DbgScreenRect(left, top, right, bottom);
	else
#endif
		DrawOverlappedWindowForAll(left, top, right, bottom);

	_video_driver->make_dirty(left, top, right - left, bottom - top);
}

void DrawDirtyBlocks(void)
{
	byte *b = _dirty_blocks;
	const int w = ALIGN(_screen.width, 64);
	const int h = ALIGN(_screen.height, 8);
	int x;
	int y;

	if (IsGeneratingWorld() && !IsGeneratingWorldReadyForPaint()) return;

	y = 0;
	do {
		x = 0;
		do {
			if (*b != 0) {
				int left;
				int top;
				int right = x + 64;
				int bottom = y;
				byte *p = b;
				int h2;

				// First try coalescing downwards
				do {
					*p = 0;
					p += DIRTY_BYTES_PER_LINE;
					bottom += 8;
				} while (bottom != h && *p != 0);

				// Try coalescing to the right too.
				h2 = (bottom - y) >> 3;
				assert(h2 > 0);
				p = b;

				while (right != w) {
					byte *p2 = ++p;
					int h = h2;
					// Check if a full line of dirty flags is set.
					do {
						if (!*p2) goto no_more_coalesc;
						p2 += DIRTY_BYTES_PER_LINE;
					} while (--h != 0);

					// Wohoo, can combine it one step to the right!
					// Do that, and clear the bits.
					right += 64;

					h = h2;
					p2 = p;
					do {
						*p2 = 0;
						p2 += DIRTY_BYTES_PER_LINE;
					} while (--h != 0);
				}
				no_more_coalesc:

				left = x;
				top = y;

				if (left   < _invalid_rect.left  ) left   = _invalid_rect.left;
				if (top    < _invalid_rect.top   ) top    = _invalid_rect.top;
				if (right  > _invalid_rect.right ) right  = _invalid_rect.right;
				if (bottom > _invalid_rect.bottom) bottom = _invalid_rect.bottom;

				if (left < right && top < bottom) {
					RedrawScreenRect(left, top, right, bottom);
				}

			}
		} while (b++, (x += 64) != w);
	} while (b += -(w >> 6) + DIRTY_BYTES_PER_LINE, (y += 8) != h);

	_invalid_rect.left = w;
	_invalid_rect.top = h;
	_invalid_rect.right = 0;
	_invalid_rect.bottom = 0;

	/* If we are generating a world, and waiting for a paint run, mark it here
	 *  as done painting, so we can continue generating. */
	if (IsGeneratingWorld() && IsGeneratingWorldReadyForPaint()) {
		SetGeneratingWorldPaintStatus(false);
	}
}


void SetDirtyBlocks(int left, int top, int right, int bottom)
{
	byte *b;
	int width;
	int height;

	if (left < 0) left = 0;
	if (top < 0) top = 0;
	if (right > _screen.width) right = _screen.width;
	if (bottom > _screen.height) bottom = _screen.height;

	if (left >= right || top >= bottom) return;

	if (left   < _invalid_rect.left  ) _invalid_rect.left   = left;
	if (top    < _invalid_rect.top   ) _invalid_rect.top    = top;
	if (right  > _invalid_rect.right ) _invalid_rect.right  = right;
	if (bottom > _invalid_rect.bottom) _invalid_rect.bottom = bottom;

	left >>= 6;
	top  >>= 3;

	b = _dirty_blocks + top * DIRTY_BYTES_PER_LINE + left;

	width  = ((right  - 1) >> 6) - left + 1;
	height = ((bottom - 1) >> 3) - top  + 1;

	assert(width > 0 && height > 0);

	do {
		int i = width;

		do b[--i] = 0xFF; while (i);

		b += DIRTY_BYTES_PER_LINE;
	} while (--height != 0);
}

void MarkWholeScreenDirty(void)
{
	SetDirtyBlocks(0, 0, _screen.width, _screen.height);
}

bool FillDrawPixelInfo(DrawPixelInfo *n, int left, int top, int width, int height)
{
	const DrawPixelInfo *o = _cur_dpi;

	n->zoom = 0;

	assert(width > 0);
	assert(height > 0);

	if ((left -= o->left) < 0) {
		width += left;
		if (width <= 0) return false;
		n->left = -left;
		left = 0;
	} else {
		n->left = 0;
	}

	if (width > o->width - left) {
		width = o->width - left;
		if (width <= 0) return false;
	}
	n->width = width;

	if ((top -= o->top) < 0) {
		height += top;
		if (height <= 0) return false;
		n->top = -top;
		top = 0;
	} else {
		n->top = 0;
	}

	n->dst_ptr = o->dst_ptr + left + top * (n->pitch = o->pitch);

	if (height > o->height - top) {
		height = o->height - top;
		if (height <= 0) return false;
	}
	n->height = height;

	return true;
}

static void SetCursorSprite(CursorID cursor)
{
	CursorVars *cv = &_cursor;
	const Sprite *p;

	if (cv->sprite == cursor) return;

	p = GetSprite(cursor & SPRITE_MASK);
	cv->sprite = cursor;
	cv->size.y = p->height;
	cv->size.x = p->width;
	cv->offs.x = p->x_offs;
	cv->offs.y = p->y_offs;

	cv->dirty = true;
}

static void SwitchAnimatedCursor(void)
{
	CursorVars *cv = &_cursor;
	const CursorID *cur = cv->animate_cur;
	CursorID sprite;

	// ANIM_CURSOR_END is 0xFFFF in table/animcursors.h
	if (cur == NULL || *cur == 0xFFFF) cur = cv->animate_list;

	sprite = cur[0];
	cv->animate_timeout = cur[1];
	cv->animate_cur = cur + 2;

	SetCursorSprite(sprite);
}

void CursorTick(void)
{
	if (_cursor.animate_timeout != 0 && --_cursor.animate_timeout == 0)
		SwitchAnimatedCursor();
}

void SetMouseCursor(CursorID cursor)
{
	// Turn off animation
	_cursor.animate_timeout = 0;
	// Set cursor
	SetCursorSprite(cursor);
}

void SetAnimatedMouseCursor(const CursorID *table)
{
	_cursor.animate_list = table;
	_cursor.animate_cur = NULL;
	SwitchAnimatedCursor();
}

bool ChangeResInGame(int w, int h)
{
	return
		(_screen.width == w && _screen.height == h) ||
		_video_driver->change_resolution(w, h);
}

void ToggleFullScreen(bool fs) {_video_driver->toggle_fullscreen(fs);}

static int CDECL compare_res(const void *pa, const void *pb)
{
	int x = ((const uint16*)pa)[0] - ((const uint16*)pb)[0];
	if (x != 0) return x;
	return ((const uint16*)pa)[1] - ((const uint16*)pb)[1];
}

void SortResolutions(int count)
{
	qsort(_resolutions, count, sizeof(_resolutions[0]), compare_res);
}