shaderOp.h

Engine/source/shaderGen/shaderOp.h
More...
Classes:

class
class
class
class
class
Detailed Description

  1
  2//-----------------------------------------------------------------------------
  3// Copyright (c) 2012 GarageGames, LLC
  4//
  5// Permission is hereby granted, free of charge, to any person obtaining a copy
  6// of this software and associated documentation files (the "Software"), to
  7// deal in the Software without restriction, including without limitation the
  8// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
  9// sell copies of the Software, and to permit persons to whom the Software is
 10// furnished to do so, subject to the following conditions:
 11//
 12// The above copyright notice and this permission notice shall be included in
 13// all copies or substantial portions of the Software.
 14//
 15// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 16// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 17// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 18// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 19// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 20// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 21// IN THE SOFTWARE.
 22//-----------------------------------------------------------------------------
 23#ifndef _SHADEROP_H_
 24#define _SHADEROP_H_
 25
 26#ifndef _LANG_ELEMENT_H_
 27#include "shaderGen/langElement.h"
 28#endif
 29
 30//**************************************************************************
 31/*!
 32   This file contains "shader operation" classes.  Originally they were
 33   to represent basic language operations like adding, assignment, etc.
 34   That proved to be far too verbose when implementing shader features,
 35   so they became more generalized helper classes.  Along with LangElement
 36   classes, they are the building blocks for the procedurally generated
 37   shaders.
 38   
 39   Each shader is a linked list of LangElements.  The list is generated
 40   when the features of the shader are processed.  When all the features
 41   are processed, then ShaderGen prints them out by traversing the linked
 42   list of LangElement and calling their print() function.
 43
 44   The ShaderOp classes are just extensions of LangElement.
 45
 46*/
 47//**************************************************************************
 48
 49
 50
 51///**************************************************************************
 52/// Shader operation base class
 53///**************************************************************************
 54class ShaderOp : public LangElement
 55{
 56protected:
 57   LangElement * mInput[2];
 58
 59public:
 60   ShaderOp( LangElement *in1, LangElement *in2 );
 61};
 62
 63//----------------------------------------------------------------------------
 64/*!
 65   DecOp - Declaration Operation - Used when declaring a variable in a shader
 66   feature.  It will automatically print the type of the variable and then
 67   the variable name.  If a shader feature set up code like:
 68
 69   @code
 70
 71   Var *foo = new Var;
 72   foo->setType( "float" );
 73   foo->setName( "foo" );
 74   LangElement *fooDecl = new DecOp( foo );
 75
 76   LangElement *statement = new GenOp( "   @ = 8.0 * 5.0;", fooDecl );
 77
 78   @endcode
 79
 80   The output in the shader file would be:
 81   
 82   @code
 83   float foo = 8.0 * 5.0;
 84   @endcode
 85*/
 86//----------------------------------------------------------------------------
 87class DecOp : public ShaderOp
 88{
 89   typedef ShaderOp Parent;
 90
 91public:
 92   DecOp( Var *in1 );
 93   virtual void print( Stream &stream );
 94};
 95
 96
 97//----------------------------------------------------------------------------
 98/*!
 99   Like the name suggests, EchoOp merely echoes back whatever string it is
100   assigned.
101*/
102//----------------------------------------------------------------------------
103class EchoOp : public ShaderOp
104{
105   typedef ShaderOp Parent;
106   const char * mStatement;
107
108public:
109   EchoOp( const char * statement );
110   ~EchoOp();
111   virtual void print( Stream &stream );
112};
113
114//----------------------------------------------------------------------------
115/*!
116   Accesses the given index on the variable
117*/
118//----------------------------------------------------------------------------
119class IndexOp : public ShaderOp
120{
121   typedef ShaderOp Parent;
122   U32 mIndex;
123
124public:
125   IndexOp( Var* var, U32 index );
126   virtual void print( Stream &stream );
127};
128
129
130//----------------------------------------------------------------------------
131/*!
132   GenOp - General Operation - Very useful for combining several variables
133   into one LangElement statement.  It uses an elipses as a parameter, so it can
134   take as many variables as you can throw at it.  It takes a string and parses
135   it for the '@' symbol which it replaces with passed in parameters.  Similar
136   to the C statement printf().  Here's an example:
137   
138   @code
139   ( assuming three variables var1, var2, var3 exist and their assigned names
140     are var1Name, var2Name, and var3Name )
141   
142   LangElement *statement = new GenOp( "  @ = @ * @.x + @.y;", var1, var1, var2, var3 );
143   
144   @endcode
145
146   The output in the shader file would be:
147   
148   @code
149   
150   var1Name = var1Name * var2Name.x + var3Name.y;
151   
152   @endcode
153*/
154//----------------------------------------------------------------------------
155class GenOp : public ShaderOp
156{
157   typedef ShaderOp Parent;
158
159   Vector<LangElement*> mElemList;
160
161public:
162   GenOp( const char * statement, ... );
163   virtual void print( Stream &stream );
164
165};
166
167#endif // _SHADEROP_H_
168