source/glsl/output.cpp

   1 #include <msp/core/raii.h>
   2 #include <msp/strings/format.h>
   3 #include "output.h"
   4
   5 using namespace std;
   6
   7 namespace Msp {
   8 namespace GL {
   9 namespace SL {
  10
  11 string Formatter::apply(Stage &s)
  12 {
  13         stage = &s;
  14         omit_builtin = true;
  15
  16         const Version &ver = s.required_features.glsl_version;
  17
  18         if(ver)
  19         {
  20                 append(format("#version %d%02d", ver.major, ver.minor));
  21                 if(s.required_features.target_api==OPENGL_ES && ver>=Version(3, 0))
  22                         append(" es");
  23                 formatted += '\n';
  24         }
  25
  26         if(s.required_features.arb_enhanced_layouts)
  27                 append("#extension GL_ARB_enhanced_layouts: require\n");
  28         if(s.required_features.arb_explicit_attrib_location)
  29                 append("#extension GL_ARB_explicit_attrib_location: require\n");
  30         if(s.required_features.arb_explicit_uniform_location)
  31                 append("#extension GL_ARB_explicit_uniform_location: require\n");
  32         if(s.required_features.arb_gpu_shader5)
  33                 append("#extension GL_ARB_gpu_shader5: require\n");
  34         if(s.required_features.arb_separate_shader_objects)
  35                 append("#extension GL_ARB_separate_shader_objects: require\n");
  36         if(s.required_features.arb_uniform_buffer_object)
  37                 append("#extension GL_ARB_uniform_buffer_object: require\n");
  38         if(s.required_features.ext_gpu_shader4)
  39                 append("#extension GL_EXT_gpu_shader4: require\n");
  40         if(s.required_features.ext_texture_array)
  41                 append("#extension GL_EXT_texture_array: require\n");
  42         formatted += '\n';
  43
  44         s.content.visit(*this);
  45
  46         return formatted;
  47 }
  48
  49 void Formatter::append(const string &text)
  50 {
  51         formatted += text;
  52         for(char c: text)
  53                 if(c=='\n')
  54                         ++source_line;
  55 }
  56
  57 void Formatter::append(char c)
  58 {
  59         formatted += c;
  60         if(c=='\n')
  61                 ++source_line;
  62 }
  63
  64 void Formatter::set_source(unsigned index, unsigned line)
  65 {
  66         if(index!=source_index || (index && line!=source_line))
  67         {
  68                 if(index==source_index && line==source_line+1)
  69                         formatted += '\n';
  70                 else
  71                 {
  72                         unsigned l = line;
  73                         if(stage && stage->required_features.glsl_version && stage->required_features.glsl_version<Version(3, 30))
  74                                 --l;
  75                         formatted += format("#line %d %d\n", l, index);
  76                 }
  77         }
  78         source_index = index;
  79         source_line = line;
  80 }
  81
  82 void Formatter::visit(Block &block)
  83 {
  84         unsigned brace_indent = indent;
  85         bool use_braces = (block.use_braces || (indent && block.body.size()!=1));
  86         if(use_braces)
  87                 append(format("%s{\n", string(brace_indent*2, ' ')));
  88
  89         SetForScope<unsigned> set(indent, indent+(indent>0 || use_braces));
  90         string spaces(indent*2, ' ');
  91         bool first = true;
  92         for(const RefPtr<Statement> &s: block.body)
  93         {
  94                 if(omit_builtin && s->source<=BUILTIN_SOURCE)
  95                         continue;
  96                 if(!first)
  97                         append('\n');
  98                 first = false;
  99                 set_source(s->source, s->line);
 100                 append(spaces);
 101                 s->visit(*this);
 102         }
 103
 104         if(use_braces)
 105                 append(format("\n%s}", string(brace_indent*2, ' ')));
 106 }
 107
 108 void Formatter::visit_expression(Expression &expr, const Operator *outer_oper, bool on_rhs)
 109 {
 110         unsigned outer_precedence = (outer_oper ? outer_oper->precedence : 20);
 111         unsigned inner_precedence = (expr.oper ? expr.oper->precedence : 0);
 112
 113         bool needs_parentheses = (inner_precedence>=outer_precedence);
 114
 115         // Omit parentheses if the outer operator encloses this operand.
 116         if(outer_oper && outer_oper->type==Operator::BINARY && outer_oper->token2[0] && on_rhs)
 117                 needs_parentheses = false;
 118
 119         if(expr.oper)
 120         {
 121                 /* Omit parentheses if the inner expression's operator sits between the
 122                 expression and the outer operator. */
 123                 bool oper_on_left = expr.oper->type==Operator::PREFIX;
 124                 bool oper_on_right = expr.oper->type==Operator::POSTFIX || (expr.oper->type==Operator::BINARY && expr.oper->token2[0]);
 125                 if(expr.oper && ((oper_on_left && on_rhs) || (oper_on_right && !on_rhs)))
 126                         needs_parentheses = false;
 127
 128                 // Omit parentheses if the operator's natural grouping works out.
 129                 if(expr.oper==outer_oper)
 130                         needs_parentheses = (expr.oper->assoc!=Operator::ASSOCIATIVE && on_rhs!=(expr.oper->assoc==Operator::RIGHT_TO_LEFT));
 131         }
 132
 133         if(needs_parentheses)
 134                 append('(');
 135         expr.visit(*this);
 136         if(needs_parentheses)
 137                 append(')');
 138 }
 139
 140 void Formatter::visit(Literal &literal)
 141 {
 142         append(literal.token);
 143 }
 144
 145 void Formatter::visit(VariableReference &var)
 146 {
 147         r_empty_name = var.name.find(' ')!=string::npos;
 148         if(!r_empty_name)
 149                 append(var.name);
 150 }
 151
 152 void Formatter::visit(MemberAccess &memacc)
 153 {
 154         visit_expression(*memacc.left, memacc.oper, false);
 155         if(!r_empty_name)
 156                 append('.');
 157         append(memacc.member);
 158         r_empty_name = false;
 159 }
 160
 161 void Formatter::visit(Swizzle &swizzle)
 162 {
 163         visit_expression(*swizzle.left, swizzle.oper, false);
 164         append(format(".%s", swizzle.component_group));
 165 }
 166
 167 void Formatter::visit(UnaryExpression &unary)
 168 {
 169         if(unary.oper->type==Operator::PREFIX)
 170                 append(unary.oper->token);
 171         visit_expression(*unary.expression, unary.oper, unary.oper->type==Operator::PREFIX);
 172         if(unary.oper->type==Operator::POSTFIX)
 173                 append(unary.oper->token);
 174 }
 175
 176 void Formatter::visit(BinaryExpression &binary)
 177 {
 178         visit_expression(*binary.left, binary.oper, false);
 179         append(binary.oper->token);
 180         visit_expression(*binary.right, binary.oper, true);
 181         if(binary.oper->token2[0])
 182                 append(binary.oper->token2);
 183 }
 184
 185 void Formatter::visit(Assignment &assign)
 186 {
 187         visit_expression(*assign.left, assign.oper, false);
 188         append(format(" %s ", assign.oper->token));
 189         visit_expression(*assign.right, assign.oper, true);
 190 }
 191
 192 void Formatter::visit(TernaryExpression &ternary)
 193 {
 194         visit_expression(*ternary.condition, ternary.oper, false);
 195         append(ternary.oper->token);
 196         visit_expression(*ternary.true_expr, ternary.oper, false);
 197         if(ternary.oper->token2[0])
 198                 append(ternary.oper->token2);
 199         visit_expression(*ternary.false_expr, ternary.oper, true);
 200 }
 201
 202 void Formatter::visit(FunctionCall &call)
 203 {
 204         append(format("%s(", call.name));
 205         for(auto i=call.arguments.begin(); i!=call.arguments.end(); ++i)
 206         {
 207                 if(i!=call.arguments.begin())
 208                         append(", ");
 209                 (*i)->visit(*this);
 210         }
 211         append(')');
 212 }
 213
 214 void Formatter::visit(ExpressionStatement &expr)
 215 {
 216         expr.expression->visit(*this);
 217         append(';');
 218 }
 219
 220 void Formatter::visit(Import &import)
 221 {
 222         append(format("import %s;", import.module));
 223 }
 224
 225 void Formatter::visit(Precision &prec)
 226 {
 227         append(format("precision %s %s;", prec.precision, prec.type));
 228 }
 229
 230 void Formatter::visit(Layout &layout)
 231 {
 232         append("layout(");
 233         for(auto i=layout.qualifiers.begin(); i!=layout.qualifiers.end(); ++i)
 234         {
 235                 if(i!=layout.qualifiers.begin())
 236                         append(", ");
 237                 append(i->name);
 238                 if(i->has_value)
 239                         append(format("=%d", i->value));
 240         }
 241         append(')');
 242 }
 243
 244 void Formatter::visit(InterfaceLayout &layout)
 245 {
 246         layout.layout.visit(*this);
 247         append(format(" %s;", layout.interface));
 248 }
 249
 250 void Formatter::visit(StructDeclaration &strct)
 251 {
 252         if(!strct.block_name.empty())
 253                 return;
 254
 255         append(format("struct %s\n", strct.name));
 256         strct.members.visit(*this);
 257         append(';');
 258 }
 259
 260 void Formatter::visit(VariableDeclaration &var)
 261 {
 262         if(var.layout)
 263         {
 264                 var.layout->visit(*this);
 265                 append(' ');
 266         }
 267         if(var.constant)
 268                 append("const ");
 269         if(!var.interpolation.empty())
 270                 append(format("%s ", var.interpolation));
 271         if(!var.sampling.empty())
 272                 append(format("%s ", var.sampling));
 273         if(!var.interface.empty())
 274         {
 275                 string interface = var.interface;
 276                 if(stage && stage->required_features.glsl_version && stage->required_features.glsl_version<Version(1, 30))
 277                 {
 278                         if(stage->type==Stage::VERTEX && var.interface=="in")
 279                                 interface = "attribute";
 280                         else if((stage->type==Stage::VERTEX && var.interface=="out") || (stage->type==Stage::FRAGMENT && var.interface=="in"))
 281                                 interface = "varying";
 282                 }
 283                 append(format("%s ", interface));
 284         }
 285         if(!var.precision.empty())
 286                 append(format("%s ", var.precision));
 287
 288         if(var.block_declaration)
 289         {
 290                 append(format("%s\n", var.block_declaration->block_name));
 291                 var.block_declaration->members.visit(*this);
 292                 if(var.name.find(' ')==string::npos)
 293                         append(format(" %s", var.name));
 294         }
 295         else
 296         {
 297                 string type_name = var.type_declaration->name;
 298                 if(var.array)
 299                         type_name = type_name.substr(0, type_name.find('['));
 300                 append(format("%s %s", type_name, var.name));
 301         }
 302
 303         if(var.array)
 304         {
 305                 append('[');
 306                 if(var.array_size)
 307                         var.array_size->visit(*this);
 308                 append(']');
 309         }
 310         if(var.init_expression)
 311         {
 312                 append(" = ");
 313                 var.init_expression->visit(*this);
 314         }
 315         if(!parameter_list)
 316                 append(';');
 317 }
 318
 319 void Formatter::visit(FunctionDeclaration &func)
 320 {
 321         append(format("%s %s(", func.return_type_declaration->name, func.name));
 322         for(auto i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 323         {
 324                 if(i!=func.parameters.begin())
 325                         append(", ");
 326                 SetFlag set(parameter_list);
 327                 (*i)->visit(*this);
 328         }
 329         append(')');
 330         if(func.definition==&func)
 331         {
 332                 append('\n');
 333                 func.body.visit(*this);
 334         }
 335         else
 336                 append(';');
 337 }
 338
 339 void Formatter::visit(Conditional &cond)
 340 {
 341         append("if(");
 342         cond.condition->visit(*this);
 343         append(")\n");
 344
 345         cond.body.visit(*this);
 346         if(!cond.else_body.body.empty())
 347         {
 348                 Conditional *else_cond = dynamic_cast<Conditional *>(cond.else_body.body.front().get());
 349                 if(cond.else_body.body.size()==1 && else_cond)
 350                 {
 351                         append('\n');
 352                         set_source(else_cond->source, else_cond->line);
 353                         append(format("%selse ", string(indent*2, ' ')));
 354                         else_cond->visit(*this);
 355                 }
 356                 else
 357                 {
 358                         append(format("\n%selse\n", string(indent*2, ' ')));
 359                         cond.else_body.visit(*this);
 360                 }
 361         }
 362 }
 363
 364 void Formatter::visit(Iteration &iter)
 365 {
 366         if(!iter.init_statement && iter.condition && !iter.loop_expression)
 367         {
 368                 append("while(");
 369                 iter.condition->visit(*this);
 370                 append(')');
 371         }
 372         else
 373         {
 374                 append("for(");
 375                 if(iter.init_statement)
 376                         iter.init_statement->visit(*this);
 377                 else
 378                         append(';');
 379                 if(iter.condition)
 380                 {
 381                         append(' ');
 382                         iter.condition->visit(*this);
 383                 }
 384                 append(';');
 385                 if(iter.loop_expression)
 386                 {
 387                         append(' ');
 388                         iter.loop_expression->visit(*this);
 389                 }
 390                 append(')');
 391         }
 392
 393         if(iter.body.body.empty())
 394                 append(" { }");
 395         else
 396         {
 397                 append('\n');
 398                 iter.body.visit(*this);
 399         }
 400 }
 401
 402 void Formatter::visit(Passthrough &pass)
 403 {
 404         append("passthrough");
 405         if(pass.subscript)
 406         {
 407                 append('[');
 408                 pass.subscript->visit(*this);
 409                 append(']');
 410         }
 411         append(';');
 412 }
 413
 414 void Formatter::visit(Return &ret)
 415 {
 416         append("return");
 417         if(ret.expression)
 418         {
 419                 append(' ');
 420                 ret.expression->visit(*this);
 421         }
 422         append(';');
 423 }
 424
 425 void Formatter::visit(Jump &jump)
 426 {
 427         append(jump.keyword);
 428         append(';');
 429 }
 430
 431 } // namespace SL
 432 } // namespace GL
 433 } // namespace Msp