aboutsummaryrefslogtreecommitdiff
path: root/scumm/gfx.h
blob: fc90953697734d92b91a3433c1e6b9186d690f0c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
/* ScummVM - Scumm Interpreter
 * Copyright (C) 2001  Ludvig Strigeus
 * Copyright (C) 2001-2005 The ScummVM project 
 *
 * 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.
 *
 * $Header$
 *
 */

#ifndef GFX_H
#define GFX_H

#include "graphics/surface.h"

namespace Scumm {

class ScummEngine;

/** Camera modes */
enum {
	kNormalCameraMode = 1,
	kFollowActorCameraMode = 2,
	kPanningCameraMode = 3
};

/** Camera state data */
struct CameraData {
	Common::Point _cur;
	Common::Point _dest;
	Common::Point _accel;
	Common::Point _last;
	int _leftTrigger, _rightTrigger;
	byte _follows, _mode;
	bool _movingToActor;
};

/** Virtual screen identifiers */
enum VirtScreenNumber {
	kMainVirtScreen = 0,	// The 'stage'
	kTextVirtScreen = 1,	// In V1-V3 games: the area where text is printed
	kVerbVirtScreen = 2,	// The verb area
	kUnkVirtScreen = 3		// ?? Not sure what this one is good for...
};

/**
 * In all Scumm games, one to four virtual screen (or 'windows') together make
 * up the content of the actual screen. Thinking of virtual screens as fixed
 * size, fixed location windows might help understanding them. Typical, in all
 * scumm games there is either one single virtual screen covering the entire
 * real screen (mostly in all newer games, e.g. Sam & Max, and all V7+ games).
 * The classic setup consists of three virtual screens: one at the top of the
 * screen, where all conversation texts are printed; then the main one (which
 * I like calling 'the stage', since all the actors are doing their stuff
 * there), and finally the lower part of the real screen is taken up by the
 * verb area.
 * Finally, in V5 games and some V6 games, it's almost the same as in the
 * original games, except that there is no separate conversation area.
 *
 * If you now wonder what the last screen is/was good for: I am not 100% sure,
 * but it appears that it was used by the original engine to display stuff
 * like the pause message, or questions ("Do you really want to restart?").
 * It seems that it is not used at all by ScummVM, so we probably could just
 * get rid of it and save a couple kilobytes of RAM.
 *
 * Each of these virtual screens has a fixed number or id (see also
 * \ref VirtScreenNumber).
 */
struct VirtScreen : Graphics::Surface {
	/**
	 * The unique id of this screen (corresponds to its position in the
	 * ScummEngine:virtscr array).
	 */
	VirtScreenNumber number;
	
	/**
	 * Vertical position of the virtual screen. Tells how much the virtual
	 * screen is shifted along the y axis relative to the real screen.
	 * If you wonder why there is no horizontal position: there is none,
	 * because all virtual screens are always exactly as wide as the
	 * real screen. This might change in the future to allow smooth
	 * horizontal scrolling in V7-V8 games.
	 */
	uint16 topline;
	
	/**
	 * Horizontal scroll offset, tells how far the screen is scrolled to the
	 * right. Only used for the main screen. After all, verbs and the
	 * conversation text box don't have to scroll.
	 */
	uint16 xstart;

	/**
	 * Flag indicating  which tells whether this screen has a back buffer or
	 * not. This is yet another feature which is only used by the main screen.
	 * Strictly spoken one could remove this variable and replace checks
	 * on it with checks on backBuf. But since some code needs to temporarily
	 * disable the backBuf (so it can abuse drawBitmap; see drawVerbBitmap()
	 * and useIm01Cursor()), we keep it (at least for now).
	 */
	bool hasTwoBuffers;
	
	/**
	 * Pointer to the screen's back buffer, if it has one (see also
	 * the hasTwoBuffers member).
	 * The backBuf is used by drawBitmap to store the background graphics of
	 * the active room. This eases redrawing: whenever a portion of the screen
	 * has to be redrawn, first a copy from the backBuf content to screenPtr is
	 * performed. Then, any objects/actors in that area are redrawn atop that.
	 */
	byte *backBuf;

	/**
	 * Array containing for each visible strip of this virtual screen the
	 * coordinate at which the dirty region of that strip starts.
	 * 't' stands for 'top' - the top coordinate of the dirty region.
	 * This together with bdirty is used to do efficient redrawing of
	 * the screen.
	 */
	uint16 tdirty[80 + 1];

	/**
	 * Array containing for each visible strip of this virtual screen the
	 * coordinate at which the dirty region of that strip end.
	 * 'b' stands for 'bottom' - the bottom coordinate of the dirty region.
	 * This together with tdirty is used to do efficient redrawing of
	 * the screen.
	 */
	uint16 bdirty[80 + 1];

	/**
	 * Convenience method to set the whole tdirty and bdirty arrays to one
	 * specific value each. This is mostly used to mark every as dirty in
	 * a single step, like so:
	 *   vs->setDirtyRange(0, vs->height);
	 * or to mark everything as clean, like so:
	 *   vs->setDirtyRange(0, 0);
	 */
	void setDirtyRange(int top, int bottom) {
		for (int i = 0; i < 80 + 1; i++) {
			tdirty[i] = top;
			bdirty[i] = bottom;
		}
	}
	
	byte *getPixels(int x, int y) const {
		return (byte *)pixels + xstart + y * pitch + x;
	}

	byte *getBackPixels(int x, int y) const {
		return (byte *)backBuf + xstart + y * pitch + x;
	}
};

/** Palette cycles */
struct ColorCycle {
	uint16 delay;
	uint16 counter;
	uint16 flags;
	byte start;
	byte end;
};

/** BlastObjects to draw */
struct BlastObject {
	uint16 number;
	Common::Rect rect;
	uint16 scaleX, scaleY;
	uint16 image;
	uint16 mode;
};

/** Bomp graphics data, used as parameter to ScummEngine::drawBomp. */
struct BompDrawData {
	Graphics::Surface dst;

	int x, y;
	byte scale_x, scale_y;
	const byte *dataptr;
	int srcwidth, srcheight;
	uint16 shadowMode;

	byte *maskPtr;
	
	BompDrawData() { memset(this, 0, sizeof(*this)); }
};

struct StripTable;

#define CHARSET_MASK_TRANSPARENCY	253

class Gdi {
	ScummEngine *_vm;

public:
	byte _transparentColor;
	int _numZBuffer;
	int _imgBufOffs[8];
	int32 _numStrips;
	
	Gdi(ScummEngine *vm);
	~Gdi();

protected:
	byte *_roomPalette;
	byte _decomp_shr, _decomp_mask;
	uint32 _vertStripNextInc;

	bool _zbufferDisabled;

	/** Flag which is true when an object is being rendered, false otherwise. */
	bool _objectMode;

	/** Render settings which are specific to the C64 graphic decoders. */
	struct {
		byte colors[4];
		byte charMap[2048], objectMap[2048], picMap[4096], colorMap[4096];
		byte maskMap[4096], maskChar[4096];
	} _C64;

	struct {
		byte nametable[16][64], nametableObj[16][64];
		byte attributes[64], attributesObj[64];
		byte masktable[16][8], masktableObj[16][8];
		int  objX;
		bool hasmask;
	} _NES;

	/** For V2 games, we cache offsets into the room graphics, to speed up things. */
	StripTable *_roomStrips;

	/* Bitmap decompressors */
	bool decompressBitmap(byte *dst, int dstPitch, const byte *src, int numLinesToProcess);

	void drawStripEGA(byte *dst, int dstPitch, const byte *src, int height) const;
	void drawStripC64Object(byte *dst, int dstPitch, int stripnr, int width, int height);
	void drawStripC64Background(byte *dst, int dstPitch, int stripnr, int height);
	void drawStripNES(byte *dst, byte *mask, int dstPitch, int stripnr, int top, int height);

	void drawStripComplex(byte *dst, int dstPitch, const byte *src, int height, const bool transpCheck) const;
	void drawStripBasicH(byte *dst, int dstPitch, const byte *src, int height, const bool transpCheck) const;
	void drawStripBasicV(byte *dst, int dstPitch, const byte *src, int height, const bool transpCheck) const;

	void unkDecode7(byte *dst, int dstPitch, const byte *src, int height) const;
	void unkDecode8(byte *dst, int dstPitch, const byte *src, int height) const;
	void unkDecode9(byte *dst, int dstPitch, const byte *src, int height) const;
	void unkDecode10(byte *dst, int dstPitch, const byte *src, int height) const;
	void unkDecode11(byte *dst, int dstPitch, const byte *src, int height) const;
	void drawStrip3DO(byte *dst, int dstPitch, const byte *src, int height, const bool transpCheck) const;

	void drawStripHE(byte *dst, int dstPitch, const byte *src, int width, int height, const bool transpCheck) const;

	/* Mask decompressors */
	void drawStripC64Mask(byte *dst, int stripnr, int width, int height) const;
	void drawStripNESMask(byte *dst, int stripnr, int height) const;
	void decompressMaskImgOr(byte *dst, const byte *src, int height) const;
	void decompressMaskImg(byte *dst, const byte *src, int height) const;

	/* Misc */
	void decodeC64Gfx(const byte *src, byte *dst, int size) const;

	int getZPlanes(const byte *smap_ptr, const byte *zplane_list[9], bool bmapImage) const;

	StripTable *generateStripTable(const byte *src, int width, int height, StripTable *table) const;
	void drawBitmapV2Helper(const byte *ptr, VirtScreen *vs, int x, int y, const int width, const int height, 
	                int stripnr, int numstrip);

public:
	void init();
	void roomChanged(byte *roomptr, uint32 IM00_offs);

	void drawBitmap(const byte *ptr, VirtScreen *vs, int x, int y, const int width, const int height,
	                int stripnr, int numstrip, byte flag);

	void decodeNESGfx(const byte *room);
	void decodeNESObject(const byte *ptr, int xpos, int ypos, int width, int height);

	void drawBMAPBg(const byte *ptr, VirtScreen *vs);
	void drawBMAPObject(const byte *ptr, VirtScreen *vs, int obj, int x, int y, int w, int h);
	
	void copyVirtScreenBuffers(Common::Rect rect, int dirtybit = 0);

	byte *getMaskBuffer(int x, int y, int z);
	void disableZBuffer() { _zbufferDisabled = true; }
	void enableZBuffer() { _zbufferDisabled = false; }

	void resetBackground(int top, int bottom, int strip);

	enum DrawBitmapFlags {
		dbAllowMaskOr   = 1 << 0,
		dbDrawMaskOnAll = 1 << 1,
		dbObjectMode    = 2 << 2
	};
};


} // End of namespace Scumm

#endif