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         append(var.name);
 148         r_empty_name = false;
 149 }
 150
 151 void Formatter::visit(InterfaceBlockReference &iface)
 152 {
 153         r_empty_name = iface.declaration->instance_name.empty();
 154         if(!r_empty_name)
 155                 append(iface.declaration->instance_name);
 156 }
 157
 158 void Formatter::visit(MemberAccess &memacc)
 159 {
 160         visit_expression(*memacc.left, memacc.oper, false);
 161         if(!r_empty_name)
 162                 append('.');
 163         append(memacc.member);
 164         r_empty_name = false;
 165 }
 166
 167 void Formatter::visit(Swizzle &swizzle)
 168 {
 169         visit_expression(*swizzle.left, swizzle.oper, false);
 170         append(format(".%s", swizzle.component_group));
 171 }
 172
 173 void Formatter::visit(UnaryExpression &unary)
 174 {
 175         if(unary.oper->type==Operator::PREFIX)
 176                 append(unary.oper->token);
 177         visit_expression(*unary.expression, unary.oper, unary.oper->type==Operator::PREFIX);
 178         if(unary.oper->type==Operator::POSTFIX)
 179                 append(unary.oper->token);
 180 }
 181
 182 void Formatter::visit(BinaryExpression &binary)
 183 {
 184         visit_expression(*binary.left, binary.oper, false);
 185         append(binary.oper->token);
 186         visit_expression(*binary.right, binary.oper, true);
 187         if(binary.oper->token2[0])
 188                 append(binary.oper->token2);
 189 }
 190
 191 void Formatter::visit(Assignment &assign)
 192 {
 193         visit_expression(*assign.left, assign.oper, false);
 194         append(format(" %s ", assign.oper->token));
 195         visit_expression(*assign.right, assign.oper, true);
 196 }
 197
 198 void Formatter::visit(TernaryExpression &ternary)
 199 {
 200         visit_expression(*ternary.condition, ternary.oper, false);
 201         append(ternary.oper->token);
 202         visit_expression(*ternary.true_expr, ternary.oper, false);
 203         if(ternary.oper->token2)
 204                 append(ternary.oper->token2);
 205         visit_expression(*ternary.false_expr, ternary.oper, true);
 206 }
 207
 208 void Formatter::visit(FunctionCall &call)
 209 {
 210         append(format("%s(", call.name));
 211         for(auto i=call.arguments.begin(); i!=call.arguments.end(); ++i)
 212         {
 213                 if(i!=call.arguments.begin())
 214                         append(", ");
 215                 (*i)->visit(*this);
 216         }
 217         append(')');
 218 }
 219
 220 void Formatter::visit(ExpressionStatement &expr)
 221 {
 222         expr.expression->visit(*this);
 223         append(';');
 224 }
 225
 226 void Formatter::visit(Import &import)
 227 {
 228         append(format("import %s;", import.module));
 229 }
 230
 231 void Formatter::visit(Precision &prec)
 232 {
 233         append(format("precision %s %s;", prec.precision, prec.type));
 234 }
 235
 236 void Formatter::visit(Layout &layout)
 237 {
 238         append("layout(");
 239         for(auto i=layout.qualifiers.begin(); i!=layout.qualifiers.end(); ++i)
 240         {
 241                 if(i!=layout.qualifiers.begin())
 242                         append(", ");
 243                 append(i->name);
 244                 if(i->has_value)
 245                         append(format("=%d", i->value));
 246         }
 247         append(')');
 248 }
 249
 250 void Formatter::visit(InterfaceLayout &layout)
 251 {
 252         layout.layout.visit(*this);
 253         append(format(" %s;", layout.interface));
 254 }
 255
 256 void Formatter::visit(StructDeclaration &strct)
 257 {
 258         append(format("struct %s\n", strct.name));
 259         strct.members.visit(*this);
 260         append(';');
 261 }
 262
 263 void Formatter::visit(VariableDeclaration &var)
 264 {
 265         if(var.layout)
 266         {
 267                 var.layout->visit(*this);
 268                 append(' ');
 269         }
 270         if(var.constant)
 271                 append("const ");
 272         if(!var.interpolation.empty())
 273                 append(format("%s ", var.interpolation));
 274         if(!var.sampling.empty())
 275                 append(format("%s ", var.sampling));
 276         if(!var.interface.empty())
 277         {
 278                 string interface = var.interface;
 279                 if(stage && stage->required_features.glsl_version && stage->required_features.glsl_version<Version(1, 30))
 280                 {
 281                         if(stage->type==Stage::VERTEX && var.interface=="in")
 282                                 interface = "attribute";
 283                         else if((stage->type==Stage::VERTEX && var.interface=="out") || (stage->type==Stage::FRAGMENT && var.interface=="in"))
 284                                 interface = "varying";
 285                 }
 286                 append(format("%s ", interface));
 287         }
 288         if(!var.precision.empty())
 289                 append(format("%s ", var.precision));
 290         string type_name = var.type_declaration->name;
 291         if(var.array)
 292                 type_name = type_name.substr(0, type_name.find('['));
 293         append(format("%s %s", type_name, var.name));
 294         if(var.array)
 295         {
 296                 append('[');
 297                 if(var.array_size)
 298                         var.array_size->visit(*this);
 299                 append(']');
 300         }
 301         if(var.init_expression)
 302         {
 303                 append(" = ");
 304                 var.init_expression->visit(*this);
 305         }
 306         if(!parameter_list)
 307                 append(';');
 308 }
 309
 310 void Formatter::visit(InterfaceBlock &iface)
 311 {
 312         if(iface.layout)
 313         {
 314                 iface.layout->visit(*this);
 315                 append(' ');
 316         }
 317         append(format("%s %s\n", iface.interface, iface.block_name));
 318         if(iface.struct_declaration)
 319                 iface.struct_declaration->members.visit(*this);
 320         if(!iface.instance_name.empty())
 321         {
 322                 append(' ');
 323                 append(iface.instance_name);
 324                 if(iface.array)
 325                         append("[]");
 326         }
 327         append(';');
 328 }
 329
 330 void Formatter::visit(FunctionDeclaration &func)
 331 {
 332         append(format("%s %s(", func.return_type_declaration->name, func.name));
 333         for(auto i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 334         {
 335                 if(i!=func.parameters.begin())
 336                         append(", ");
 337                 SetFlag set(parameter_list);
 338                 (*i)->visit(*this);
 339         }
 340         append(')');
 341         if(func.definition==&func)
 342         {
 343                 append('\n');
 344                 func.body.visit(*this);
 345         }
 346         else
 347                 append(';');
 348 }
 349
 350 void Formatter::visit(Conditional &cond)
 351 {
 352         append("if(");
 353         cond.condition->visit(*this);
 354         append(")\n");
 355
 356         cond.body.visit(*this);
 357         if(!cond.else_body.body.empty())
 358         {
 359                 Conditional *else_cond = dynamic_cast<Conditional *>(cond.else_body.body.front().get());
 360                 if(cond.else_body.body.size()==1 && else_cond)
 361                 {
 362                         append('\n');
 363                         set_source(else_cond->source, else_cond->line);
 364                         append(format("%selse ", string(indent*2, ' ')));
 365                         else_cond->visit(*this);
 366                 }
 367                 else
 368                 {
 369                         append(format("\n%selse\n", string(indent*2, ' ')));
 370                         cond.else_body.visit(*this);
 371                 }
 372         }
 373 }
 374
 375 void Formatter::visit(Iteration &iter)
 376 {
 377         if(!iter.init_statement && iter.condition && !iter.loop_expression)
 378         {
 379                 append("while(");
 380                 iter.condition->visit(*this);
 381                 append(')');
 382         }
 383         else
 384         {
 385                 append("for(");
 386                 if(iter.init_statement)
 387                         iter.init_statement->visit(*this);
 388                 else
 389                         append(';');
 390                 if(iter.condition)
 391                 {
 392                         append(' ');
 393                         iter.condition->visit(*this);
 394                 }
 395                 append(';');
 396                 if(iter.loop_expression)
 397                 {
 398                         append(' ');
 399                         iter.loop_expression->visit(*this);
 400                 }
 401                 append(')');
 402         }
 403
 404         if(iter.body.body.empty())
 405                 append(" { }");
 406         else
 407         {
 408                 append('\n');
 409                 iter.body.visit(*this);
 410         }
 411 }
 412
 413 void Formatter::visit(Passthrough &pass)
 414 {
 415         append("passthrough");
 416         if(pass.subscript)
 417         {
 418                 append('[');
 419                 pass.subscript->visit(*this);
 420                 append(']');
 421         }
 422         append(';');
 423 }
 424
 425 void Formatter::visit(Return &ret)
 426 {
 427         append("return");
 428         if(ret.expression)
 429         {
 430                 append(' ');
 431                 ret.expression->visit(*this);
 432         }
 433         append(';');
 434 }
 435
 436 void Formatter::visit(Jump &jump)
 437 {
 438         append(jump.keyword);
 439         append(';');
 440 }
 441
 442 } // namespace SL
 443 } // namespace GL
 444 } // namespace Msp