summaryrefslogtreecommitdiff
path: root/newgrf_spritegroup.c
blob: 1935dd4ea70281e60a72ee0aaed43ce442ec89a7 (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
/* $Id$ */

#include "stdafx.h"
#include "openttd.h"
#include "variables.h"
#include "macros.h"
#include "pool.h"
#include "newgrf_spritegroup.h"
#include "date.h"

static void SpriteGroupPoolCleanBlock(uint start_item, uint end_item);

static uint _spritegroup_count = 0;
STATIC_POOL(SpriteGroup, SpriteGroup, 4, 8000, NULL, SpriteGroupPoolCleanBlock);

void DestroySpriteGroup(SpriteGroup *group)
{
	/* Free dynamically allocated memory */
	/* XXX Cast away the consts due to MSVC being buggy... */
	switch (group->type) {
		case SGT_REAL:
			free((SpriteGroup**)group->g.real.loaded);
			free((SpriteGroup**)group->g.real.loading);
			break;

		case SGT_DETERMINISTIC:
			free(group->g.determ.adjusts);
			free(group->g.determ.ranges);
			break;

		case SGT_RANDOMIZED:
			free((SpriteGroup**)group->g.random.groups);
			break;

		default:
			break;
	}
}

static void SpriteGroupPoolCleanBlock(uint start_item, uint end_item)
{
	uint i;

	for (i = start_item; i <= end_item; i++) {
		DestroySpriteGroup(GetSpriteGroup(i));
	}
}


/* Allocate a new SpriteGroup */
SpriteGroup *AllocateSpriteGroup(void)
{
	/* This is totally different to the other pool allocators, as we never remove an item from the pool. */
	if (_spritegroup_count == GetSpriteGroupPoolSize()) {
		if (!AddBlockToPool(&_SpriteGroup_pool)) return NULL;
	}

	return GetSpriteGroup(_spritegroup_count++);
}


void InitializeSpriteGroupPool(void)
{
	CleanPool(&_SpriteGroup_pool);

	_spritegroup_count = 0;
}


static inline uint32 GetVariable(const ResolverObject *object, byte variable, byte parameter, bool *available)
{
	/* Return common variables */
	switch (variable) {
		case 0x00: return max(_date - DAYS_TILL_ORIGINAL_BASE_YEAR, 0);
		case 0x01: return clamp(_cur_year, ORIGINAL_BASE_YEAR, ORIGINAL_MAX_YEAR) - ORIGINAL_BASE_YEAR;
		case 0x02: return _cur_month;
		case 0x03: return _opt.landscape;
		case 0x09: return _date_fract;
		case 0x0A: return _tick_counter;
		case 0x0C: return object->callback;
		case 0x10: return object->callback_param1;
		case 0x11: return 0;
		case 0x18: return object->callback_param2;
		case 0x1A: return -1;
		case 0x1B: return GB(_display_opt, 0, 6);
		case 0x1C: return object->last_value;
		case 0x20: return _opt.landscape == LT_HILLY ? _opt.snow_line : 0xFF;

		/* Not a common variable, so evalute the feature specific variables */
		default: return object->GetVariable(object, variable, parameter, available);
	}
}


/* Evaluate an adjustment for a variable of the given size. This is a bit of
 * an unwieldy macro, but it saves triplicating the code. */
#define BUILD_EVAL_ADJUST(size, usize) \
static inline usize EvalAdjust_ ## size(const DeterministicSpriteGroupAdjust *adjust, usize last_value, int32 value) \
{ \
	value >>= adjust->shift_num; \
	value  &= adjust->and_mask; \
\
	if (adjust->type != DSGA_TYPE_NONE) value += (size)adjust->add_val; \
\
	switch (adjust->type) { \
		case DSGA_TYPE_DIV:  value /= (size)adjust->divmod_val; break; \
		case DSGA_TYPE_MOD:  value %= (usize)adjust->divmod_val; break; \
		case DSGA_TYPE_NONE: break; \
	} \
\
	/* Get our value to the correct range */ \
	value = (usize)value; \
\
	switch (adjust->operation) { \
		case DSGA_OP_ADD:  return last_value + value; \
		case DSGA_OP_SUB:  return last_value - value; \
		case DSGA_OP_SMIN: return min(last_value, value); \
		case DSGA_OP_SMAX: return max(last_value, value); \
		case DSGA_OP_UMIN: return min((usize)last_value, (usize)value); \
		case DSGA_OP_UMAX: return max((usize)last_value, (usize)value); \
		case DSGA_OP_SDIV: return last_value / value; \
		case DSGA_OP_SMOD: return last_value % value; \
		case DSGA_OP_UDIV: return (usize)last_value / (usize)value; \
		case DSGA_OP_UMOD: return (usize)last_value % (usize)value; \
		case DSGA_OP_MUL:  return last_value * value; \
		case DSGA_OP_AND:  return last_value & value; \
		case DSGA_OP_OR:   return last_value | value; \
		case DSGA_OP_XOR:  return last_value ^ value; \
		default:           return value; \
	} \
}


BUILD_EVAL_ADJUST(int8, uint8)
BUILD_EVAL_ADJUST(int16, uint16)
BUILD_EVAL_ADJUST(int32, uint32)


static inline const SpriteGroup *ResolveVariable(const SpriteGroup *group, ResolverObject *object)
{
	static SpriteGroup nvarzero;
	int32 last_value = object->last_value;
	int32 value = -1;
	uint i;

	object->scope = group->g.determ.var_scope;

	for (i = 0; i < group->g.determ.num_adjusts; i++) {
		DeterministicSpriteGroupAdjust *adjust = &group->g.determ.adjusts[i];

		/* Try to get the variable. We shall assume it is available, unless told otherwise. */
		bool available = true;
		value = GetVariable(object, adjust->variable, adjust->parameter, &available);

		if (!available) {
			/* Unsupported property: skip further processing and return either
			 * the group from the first range or the default group. */
			return Resolve(group->g.determ.num_ranges > 0 ? group->g.determ.ranges[0].group : group->g.determ.default_group, object);
		}

		switch (group->g.determ.size) {
			case DSG_SIZE_BYTE:  value = EvalAdjust_int8(adjust, last_value, value); break;
			case DSG_SIZE_WORD:  value = EvalAdjust_int16(adjust, last_value, value); break;
			case DSG_SIZE_DWORD: value = EvalAdjust_int32(adjust, last_value, value); break;
			default: NOT_REACHED(); break;
		}
		last_value = value;
	}

	if (group->g.determ.num_ranges == 0) {
		/* nvar == 0 is a special case -- we turn our value into a callback result */
		nvarzero.type = SGT_CALLBACK;
		nvarzero.g.callback.result = GB(value, 0, 15);
		return &nvarzero;
	}

	for (i = 0; i < group->g.determ.num_ranges; i++) {
		if (group->g.determ.ranges[i].low <= (uint32)value && (uint32)value <= group->g.determ.ranges[i].high) {
			return Resolve(group->g.determ.ranges[i].group, object);
		}
	}

	return Resolve(group->g.determ.default_group, object);
}


static inline const SpriteGroup *ResolveRandom(const SpriteGroup *group, ResolverObject *object)
{
	uint32 mask;
	byte index;

	object->scope = group->g.random.var_scope;

	if (object->trigger != 0) {
		/* Handle triggers */
		/* Magic code that may or may not do the right things... */
		byte waiting_triggers = object->GetTriggers(object);
		byte match = group->g.random.triggers & (waiting_triggers | object->trigger);
		bool res;

		res = (group->g.random.cmp_mode == RSG_CMP_ANY) ?
			(match != 0) : (match == group->g.random.triggers);

		if (res) {
			waiting_triggers &= ~match;
			object->reseed |= (group->g.random.num_groups - 1) << group->g.random.lowest_randbit;
		} else {
			waiting_triggers |= object->trigger;
		}

		object->SetTriggers(object, waiting_triggers);
	}

	mask  = (group->g.random.num_groups - 1) << group->g.random.lowest_randbit;
	index = (object->GetRandomBits(object) & mask) >> group->g.random.lowest_randbit;

	return Resolve(group->g.random.groups[index], object);
}


/* ResolverObject (re)entry point */
const SpriteGroup *Resolve(const SpriteGroup *group, ResolverObject *object)
{
	/* We're called even if there is no group, so quietly return nothing */
	if (group == NULL) return NULL;

	switch (group->type) {
		case SGT_REAL:          return object->ResolveReal(object, group);
		case SGT_DETERMINISTIC: return ResolveVariable(group, object);
		case SGT_RANDOMIZED:    return ResolveRandom(group, object);
		default:                return group;
	}
}