src/newgrf_spritegroup.cpp

   1 /* $Id$ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * OpenTTD 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, version 2.
   6  * OpenTTD 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.
   7  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   8  */
   9
  10 /** @file newgrf_spritegroup.cpp Handling of primarily NewGRF action 2. */
  11
  12 #include "stdafx.h"
  13 #include <algorithm>
  14 #include "debug.h"
  15 #include "newgrf_spritegroup.h"
  16 #include "core/pool_func.hpp"
  17
  18 #include "safeguards.h"
  19
  20 SpriteGroupPool _spritegroup_pool("SpriteGroup");
  21 INSTANTIATE_POOL_METHODS(SpriteGroup)
  22
  23 TemporaryStorageArray<int32, 0x110> _temp_store;
  24
  25
  26 /**
  27  * ResolverObject (re)entry point.
  28  * This cannot be made a call to a virtual function because virtual functions
  29  * do not like nullptr and checking for nullptr *everywhere* is more cumbersome than
  30  * this little helper function.
  31  * @param group the group to resolve for
  32  * @param object information needed to resolve the group
  33  * @param top_level true if this is a top-level SpriteGroup, false if used nested in another SpriteGroup.
  34  * @return the resolved group
  35  */
  36 /* static */ const SpriteGroup *SpriteGroup::Resolve(const SpriteGroup *group, ResolverObject &object, bool top_level)
  37 {
  38         if (group == nullptr) return nullptr;
  39         if (top_level) {
  40                 _temp_store.ClearChanges();
  41         }
  42         return group->Resolve(object);
  43 }
  44
  45 RealSpriteGroup::~RealSpriteGroup()
  46 {
  47         free(this->loaded);
  48         free(this->loading);
  49 }
  50
  51 DeterministicSpriteGroup::~DeterministicSpriteGroup()
  52 {
  53         free(this->adjusts);
  54         free(this->ranges);
  55 }
  56
  57 RandomizedSpriteGroup::~RandomizedSpriteGroup()
  58 {
  59         free(this->groups);
  60 }
  61
  62 static inline uint32 GetVariable(const ResolverObject &object, ScopeResolver *scope, byte variable, uint32 parameter, bool *available)
  63 {
  64         uint32 value;
  65         switch (variable) {
  66                 case 0x0C: return object.callback;
  67                 case 0x10: return object.callback_param1;
  68                 case 0x18: return object.callback_param2;
  69                 case 0x1C: return object.last_value;
  70
  71                 case 0x5F: return (scope->GetRandomBits() << 8) | scope->GetTriggers();
  72
  73                 case 0x7D: return _temp_store.GetValue(parameter);
  74
  75                 case 0x7F:
  76                         if (object.grffile == nullptr) return 0;
  77                         return object.grffile->GetParam(parameter);
  78
  79                 default:
  80                         /* First handle variables common with Action7/9/D */
  81                         if (variable < 0x40 && GetGlobalVariable(variable, &value, object.grffile)) return value;
  82                         /* Not a common variable, so evaluate the feature specific variables */
  83                         return scope->GetVariable(variable, parameter, available);
  84         }
  85 }
  86
  87 /**
  88  * Get a few random bits. Default implementation has no random bits.
  89  * @return Random bits.
  90  */
  91 /* virtual */ uint32 ScopeResolver::GetRandomBits() const
  92 {
  93         return 0;
  94 }
  95
  96 /**
  97  * Get the triggers. Base class returns \c 0 to prevent trouble.
  98  * @return The triggers.
  99  */
 100 /* virtual */ uint32 ScopeResolver::GetTriggers() const
 101 {
 102         return 0;
 103 }
 104
 105 /**
 106  * Get a variable value. Default implementation has no available variables.
 107  * @param variable Variable to read
 108  * @param parameter Parameter for 60+x variables
 109  * @param[out] available Set to false, in case the variable does not exist.
 110  * @return Value
 111  */
 112 /* virtual */ uint32 ScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
 113 {
 114         DEBUG(grf, 1, "Unhandled scope variable 0x%X", variable);
 115         *available = false;
 116         return UINT_MAX;
 117 }
 118
 119 /**
 120  * Store a value into the persistent storage area (PSA). Default implementation does nothing (for newgrf classes without storage).
 121  * @param pos Position to store into.
 122  * @param value Value to store.
 123  */
 124 /* virtual */ void ScopeResolver::StorePSA(uint reg, int32 value) {}
 125
 126 /**
 127  * Get the real sprites of the grf.
 128  * @param group Group to get.
 129  * @return The available sprite group.
 130  */
 131 /* virtual */ const SpriteGroup *ResolverObject::ResolveReal(const RealSpriteGroup *group) const
 132 {
 133         return nullptr;
 134 }
 135
 136 /**
 137  * Get a resolver for the \a scope.
 138  * @param scope Scope to return.
 139  * @param relative Additional parameter for #VSG_SCOPE_RELATIVE.
 140  * @return The resolver for the requested scope.
 141  */
 142 /* virtual */ ScopeResolver *ResolverObject::GetScope(VarSpriteGroupScope scope, byte relative)
 143 {
 144         return &this->default_scope;
 145 }
 146
 147 /**
 148  * Rotate val rot times to the right
 149  * @param val the value to rotate
 150  * @param rot the amount of times to rotate
 151  * @return the rotated value
 152  */
 153 static uint32 RotateRight(uint32 val, uint32 rot)
 154 {
 155         /* Do not rotate more than necessary */
 156         rot %= 32;
 157
 158         return (val >> rot) | (val << (32 - rot));
 159 }
 160
 161 /* Evaluate an adjustment for a variable of the given size.
 162  * U is the unsigned type and S is the signed type to use. */
 163 template <typename U, typename S>
 164 static U EvalAdjustT(const DeterministicSpriteGroupAdjust *adjust, ScopeResolver *scope, U last_value, uint32 value)
 165 {
 166         value >>= adjust->shift_num;
 167         value  &= adjust->and_mask;
 168
 169         switch (adjust->type) {
 170                 case DSGA_TYPE_DIV:  value = ((S)value + (S)adjust->add_val) / (S)adjust->divmod_val; break;
 171                 case DSGA_TYPE_MOD:  value = ((S)value + (S)adjust->add_val) % (S)adjust->divmod_val; break;
 172                 case DSGA_TYPE_NONE: break;
 173         }
 174
 175         switch (adjust->operation) {
 176                 case DSGA_OP_ADD:  return last_value + value;
 177                 case DSGA_OP_SUB:  return last_value - value;
 178                 case DSGA_OP_SMIN: return min((S)last_value, (S)value);
 179                 case DSGA_OP_SMAX: return max((S)last_value, (S)value);
 180                 case DSGA_OP_UMIN: return min((U)last_value, (U)value);
 181                 case DSGA_OP_UMAX: return max((U)last_value, (U)value);
 182                 case DSGA_OP_SDIV: return value == 0 ? (S)last_value : (S)last_value / (S)value;
 183                 case DSGA_OP_SMOD: return value == 0 ? (S)last_value : (S)last_value % (S)value;
 184                 case DSGA_OP_UDIV: return value == 0 ? (U)last_value : (U)last_value / (U)value;
 185                 case DSGA_OP_UMOD: return value == 0 ? (U)last_value : (U)last_value % (U)value;
 186                 case DSGA_OP_MUL:  return last_value * value;
 187                 case DSGA_OP_AND:  return last_value & value;
 188                 case DSGA_OP_OR:   return last_value | value;
 189                 case DSGA_OP_XOR:  return last_value ^ value;
 190                 case DSGA_OP_STO:  _temp_store.StoreValue((U)value, (S)last_value); return last_value;
 191                 case DSGA_OP_RST:  return value;
 192                 case DSGA_OP_STOP: scope->StorePSA((U)value, (S)last_value); return last_value;
 193                 case DSGA_OP_ROR:  return RotateRight(last_value, value);
 194                 case DSGA_OP_SCMP: return ((S)last_value == (S)value) ? 1 : ((S)last_value < (S)value ? 0 : 2);
 195                 case DSGA_OP_UCMP: return ((U)last_value == (U)value) ? 1 : ((U)last_value < (U)value ? 0 : 2);
 196                 case DSGA_OP_SHL:  return (uint32)(U)last_value << ((U)value & 0x1F); // Same behaviour as in ParamSet, mask 'value' to 5 bits, which should behave the same on all architectures.
 197                 case DSGA_OP_SHR:  return (uint32)(U)last_value >> ((U)value & 0x1F);
 198                 case DSGA_OP_SAR:  return (int32)(S)last_value >> ((U)value & 0x1F);
 199                 default:           return value;
 200         }
 201 }
 202
 203
 204 static bool RangeHighComparator(const DeterministicSpriteGroupRange& range, uint32 value)
 205 {
 206         return range.high < value;
 207 }
 208
 209 const SpriteGroup *DeterministicSpriteGroup::Resolve(ResolverObject &object) const
 210 {
 211         uint32 last_value = 0;
 212         uint32 value = 0;
 213         uint i;
 214
 215         ScopeResolver *scope = object.GetScope(this->var_scope);
 216
 217         for (i = 0; i < this->num_adjusts; i++) {
 218                 DeterministicSpriteGroupAdjust *adjust = &this->adjusts[i];
 219
 220                 /* Try to get the variable. We shall assume it is available, unless told otherwise. */
 221                 bool available = true;
 222                 if (adjust->variable == 0x7E) {
 223                         const SpriteGroup *subgroup = SpriteGroup::Resolve(adjust->subroutine, object, false);
 224                         if (subgroup == nullptr) {
 225                                 value = CALLBACK_FAILED;
 226                         } else {
 227                                 value = subgroup->GetCallbackResult();
 228                         }
 229
 230                         /* Note: 'last_value' and 'reseed' are shared between the main chain and the procedure */
 231                 } else if (adjust->variable == 0x7B) {
 232                         value = GetVariable(object, scope, adjust->parameter, last_value, &available);
 233                 } else {
 234                         value = GetVariable(object, scope, adjust->variable, adjust->parameter, &available);
 235                 }
 236
 237                 if (!available) {
 238                         /* Unsupported variable: skip further processing and return either
 239                          * the group from the first range or the default group. */
 240                         return SpriteGroup::Resolve(this->error_group, object, false);
 241                 }
 242
 243                 bool possible_div_by_zero = (value == 0 && (adjust->operation == DSGA_OP_UDIV ||
 244                                                                                                         adjust->operation == DSGA_OP_UMOD ||
 245                                                                                                         adjust->operation == DSGA_OP_SDIV ||
 246                                                                                                         adjust->operation == DSGA_OP_SMOD));
 247
 248                 if (possible_div_by_zero) {
 249                         value = last_value;
 250                 }
 251                 else
 252                 {
 253                         switch (this->size) {
 254                                 case DSG_SIZE_BYTE:  value = EvalAdjustT<uint8, int8>(adjust, scope, last_value, value); break;
 255                                 case DSG_SIZE_WORD:  value = EvalAdjustT<uint16, int16>(adjust, scope, last_value, value); break;
 256                                 case DSG_SIZE_DWORD: value = EvalAdjustT<uint32, int32>(adjust, scope, last_value, value); break;
 257                                 default: NOT_REACHED();
 258                         }
 259                 }
 260
 261                 last_value = value;
 262         }
 263
 264         object.last_value = last_value;
 265
 266         if (this->calculated_result) {
 267                 /* nvar == 0 is a special case -- we turn our value into a callback result */
 268                 if (value != CALLBACK_FAILED) value = GB(value, 0, 15);
 269                 static CallbackResultSpriteGroup nvarzero(0, true);
 270                 nvarzero.result = value;
 271                 return &nvarzero;
 272         }
 273
 274         if (this->num_ranges > 4) {
 275                 DeterministicSpriteGroupRange *lower = std::lower_bound(this->ranges + 0, this->ranges + this->num_ranges, value, RangeHighComparator);
 276                 if (lower != this->ranges + this->num_ranges && lower->low <= value) {
 277                         assert(lower->low <= value && value <= lower->high);
 278                         return SpriteGroup::Resolve(lower->group, object, false);
 279                 }
 280         } else {
 281                 for (i = 0; i < this->num_ranges; i++) {
 282                         if (this->ranges[i].low <= value && value <= this->ranges[i].high) {
 283                                 return SpriteGroup::Resolve(this->ranges[i].group, object, false);
 284                         }
 285                 }
 286         }
 287
 288         return SpriteGroup::Resolve(this->default_group, object, false);
 289 }
 290
 291
 292 const SpriteGroup *RandomizedSpriteGroup::Resolve(ResolverObject &object) const
 293 {
 294         ScopeResolver *scope = object.GetScope(this->var_scope, this->count);
 295         if (object.callback == CBID_RANDOM_TRIGGER) {
 296                 /* Handle triggers */
 297                 byte match = this->triggers & object.waiting_triggers;
 298                 bool res = (this->cmp_mode == RSG_CMP_ANY) ? (match != 0) : (match == this->triggers);
 299
 300                 if (res) {
 301                         object.used_triggers |= match;
 302                         object.reseed[this->var_scope] |= (this->num_groups - 1) << this->lowest_randbit;
 303                 }
 304         }
 305
 306         uint32 mask  = (this->num_groups - 1) << this->lowest_randbit;
 307         byte index = (scope->GetRandomBits() & mask) >> this->lowest_randbit;
 308
 309         return SpriteGroup::Resolve(this->groups[index], object, false);
 310 }
 311
 312
 313 const SpriteGroup *RealSpriteGroup::Resolve(ResolverObject &object) const
 314 {
 315         return object.ResolveReal(this);
 316 }
 317
 318 /**
 319  * Process registers and the construction stage into the sprite layout.
 320  * The passed construction stage might get reset to zero, if it gets incorporated into the layout
 321  * during the preprocessing.
 322  * @param [in, out] stage Construction stage (0-3), or nullptr if not applicable.
 323  * @return sprite layout to draw.
 324  */
 325 const DrawTileSprites *TileLayoutSpriteGroup::ProcessRegisters(uint8 *stage) const
 326 {
 327         if (!this->dts.NeedsPreprocessing()) {
 328                 if (stage != nullptr && this->dts.consistent_max_offset > 0) *stage = GetConstructionStageOffset(*stage, this->dts.consistent_max_offset);
 329                 return &this->dts;
 330         }
 331
 332         static DrawTileSprites result;
 333         uint8 actual_stage = stage != nullptr ? *stage : 0;
 334         this->dts.PrepareLayout(0, 0, 0, actual_stage, false);
 335         this->dts.ProcessRegisters(0, 0, false);
 336         result.seq = this->dts.GetLayout(&result.ground);
 337
 338         /* Stage has been processed by PrepareLayout(), set it to zero. */
 339         if (stage != nullptr) *stage = 0;
 340
 341         return &result;
 342 }