KiCad PCB EDA Suite
shader.cpp
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1 /*
2  * This program source code file is part of KICAD, a free EDA CAD application.
3  *
4  * Copyright (C) 2012 Torsten Hueter, torstenhtr <at> gmx.de
5  * Copyright (C) 2012-2021 Kicad Developers, see AUTHORS.txt for contributors.
6  *
7  * Graphics Abstraction Layer (GAL) for OpenGL
8  *
9  * Shader class
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License
13  * as published by the Free Software Foundation; either version 2
14  * of the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, you may find one here:
23  * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
24  * or you may search the http://www.gnu.org website for the version 2 license,
25  * or you may write to the Free Software Foundation, Inc.,
26  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
27  */
28 
29 #include <iostream>
30 #include <fstream>
31 #include <stdexcept>
32 
33 #include <cstring>
34 #include <cassert>
35 
36 #include <gal/opengl/shader.h>
37 #include <vector>
38 
39 using namespace KIGFX;
40 
42  isProgramCreated( false ),
43  isShaderLinked( false ),
44  active( false ),
45  maximumVertices( 4 ),
46  geomInputType( GL_LINES ),
47  geomOutputType( GL_LINES )
48 
49 {
50  // Do not have uninitialized members:
51  programNumber = 0;
52 }
53 
54 
56 {
57  if( active )
58  Deactivate();
59 
60  if( isProgramCreated )
61  {
62  if( glIsShader )
63  {
64  // Delete the shaders and the program
65  for( std::deque<GLuint>::iterator it = shaderNumbers.begin(); it != shaderNumbers.end();
66  ++it )
67  {
68  GLuint shader = *it;
69 
70  if( glIsShader( shader ) )
71  {
72  glDetachShader( programNumber, shader );
73  glDeleteShader( shader );
74  }
75  }
76 
77  glDeleteProgram( programNumber );
78  }
79  }
80 }
81 
82 
83 bool SHADER::LoadShaderFromFile( SHADER_TYPE aShaderType, const std::string& aShaderSourceName )
84 {
85  // Load shader sources
86  const std::string shaderSource = ReadSource( aShaderSourceName );
87 
88  return LoadShaderFromStrings( aShaderType, shaderSource );
89 }
90 
91 
92 void SHADER::ConfigureGeometryShader( GLuint maxVertices, GLuint geometryInputType,
93  GLuint geometryOutputType )
94 {
95  maximumVertices = maxVertices;
96  geomInputType = geometryInputType;
97  geomOutputType = geometryOutputType;
98 }
99 
100 
102 {
103  // Shader linking
104  glLinkProgram( programNumber );
106 
107  // Check the Link state
108  GLint tmp;
109  glGetObjectParameterivARB( programNumber, GL_OBJECT_LINK_STATUS_ARB, &tmp );
110  isShaderLinked = !!tmp;
111 
112 #ifdef DEBUG
113  if( !isShaderLinked )
114  {
115  int maxLength;
116  glGetProgramiv( programNumber, GL_INFO_LOG_LENGTH, &maxLength );
117  maxLength = maxLength + 1;
118  char* linkInfoLog = new char[maxLength];
119  glGetProgramInfoLog( programNumber, maxLength, &maxLength, linkInfoLog );
120  std::cerr << "Shader linking error:" << std::endl;
121  std::cerr << linkInfoLog;
122  delete[] linkInfoLog;
123  }
124 #endif /* DEBUG */
125 
126  return isShaderLinked;
127 }
128 
129 
130 int SHADER::AddParameter( const std::string& aParameterName )
131 {
132  GLint location = glGetUniformLocation( programNumber, aParameterName.c_str() );
133 
134  if( location >= 0 )
135  parameterLocation.push_back( location );
136  else
137  throw std::runtime_error( "Could not find shader uniform: " + aParameterName );
138 
139  return parameterLocation.size() - 1;
140 }
141 
142 
143 void SHADER::SetParameter( int parameterNumber, float value ) const
144 {
145  assert( (unsigned) parameterNumber < parameterLocation.size() );
146 
147  glUniform1f( parameterLocation[parameterNumber], value );
148 }
149 
150 
151 void SHADER::SetParameter( int parameterNumber, int value ) const
152 {
153  assert( (unsigned) parameterNumber < parameterLocation.size() );
154 
155  glUniform1i( parameterLocation[parameterNumber], value );
156 }
157 
158 void SHADER::SetParameter( int parameterNumber, float f0, float f1, float f2, float f3 ) const
159 {
160  assert( (unsigned) parameterNumber < parameterLocation.size() );
161  float arr[4] = { f0, f1, f2, f3 };
162  glUniform4fv( parameterLocation[parameterNumber], 1, arr );
163 }
164 
165 void SHADER::SetParameter( int aParameterNumber, const VECTOR2D& aValue ) const
166 {
167  assert( (unsigned) aParameterNumber < parameterLocation.size() );
168  glUniform2f( parameterLocation[aParameterNumber], aValue.x, aValue.y );
169 }
170 
171 
172 int SHADER::GetAttribute( const std::string& aAttributeName ) const
173 {
174  return glGetAttribLocation( programNumber, aAttributeName.c_str() );
175 }
176 
177 
179 {
180  GLint glInfoLogLength = 0;
181  GLint writtenChars = 0;
182 
183  // Get the length of the info string
184  glGetProgramiv( aProgram, GL_INFO_LOG_LENGTH, &glInfoLogLength );
185 
186  // Print the information
187  if( glInfoLogLength > 2 )
188  {
189  GLchar* glInfoLog = new GLchar[glInfoLogLength];
190  glGetProgramInfoLog( aProgram, glInfoLogLength, &writtenChars, glInfoLog );
191 
192  delete[] glInfoLog;
193  }
194 }
195 
196 
197 void SHADER::shaderInfo( GLuint aShader )
198 {
199  GLint glInfoLogLength = 0;
200  GLint writtenChars = 0;
201 
202  // Get the length of the info string
203  glGetShaderiv( aShader, GL_INFO_LOG_LENGTH, &glInfoLogLength );
204 
205  // Print the information
206  if( glInfoLogLength > 2 )
207  {
208  GLchar* glInfoLog = new GLchar[glInfoLogLength];
209  glGetShaderInfoLog( aShader, glInfoLogLength, &writtenChars, glInfoLog );
210 
211  delete[] glInfoLog;
212  }
213 }
214 
215 
216 std::string SHADER::ReadSource( const std::string& aShaderSourceName )
217 {
218  // Open the shader source for reading
219  std::ifstream inputFile( aShaderSourceName.c_str(), std::ifstream::in );
220  std::string shaderSource;
221 
222  if( !inputFile )
223  throw std::runtime_error( "Can't read the shader source: " + aShaderSourceName );
224 
225  std::string shaderSourceLine;
226 
227  // Read all lines from the text file
228  while( getline( inputFile, shaderSourceLine ) )
229  {
230  shaderSource += shaderSourceLine;
231  shaderSource += "\n";
232  }
233 
234  return shaderSource;
235 }
236 
237 
238 bool SHADER::loadShaderFromStringArray( SHADER_TYPE aShaderType, const char** aArray, size_t aSize )
239 {
240  assert( !isShaderLinked );
241 
242  // Create the program
243  if( !isProgramCreated )
244  {
245  programNumber = glCreateProgram();
246  isProgramCreated = true;
247  }
248 
249  // Create a shader
250  GLuint shaderNumber = glCreateShader( aShaderType );
251  shaderNumbers.push_back( shaderNumber );
252 
253  // Get the program info
255 
256  // Attach the sources
257  glShaderSource( shaderNumber, aSize, (const GLchar**) aArray, nullptr );
259 
260  // Compile and attach shader to the program
261  glCompileShader( shaderNumber );
262  GLint status;
263  glGetShaderiv( shaderNumber, GL_COMPILE_STATUS, &status );
264 
265  if( status != GL_TRUE )
266  {
267  shaderInfo( shaderNumber );
268 
269  GLint maxLength = 0;
270  glGetShaderiv( shaderNumber, GL_INFO_LOG_LENGTH, &maxLength );
271 
272  // The maxLength includes the NULL character
273  std::vector<GLchar> errorLog( (size_t) maxLength );
274  glGetShaderInfoLog( shaderNumber, maxLength, &maxLength, &errorLog[0] );
275 
276  // Provide the infolog in whatever manor you deem best.
277  // Exit with failure.
278  glDeleteShader( shaderNumber ); // Don't leak the shader.
279 
280  throw std::runtime_error( &errorLog[0] );
281  }
282 
283  glAttachShader( programNumber, shaderNumber );
285 
286  // Special handling for the geometry shader
287  if( aShaderType == SHADER_TYPE_GEOMETRY )
288  {
289  glProgramParameteriEXT( programNumber, GL_GEOMETRY_VERTICES_OUT_EXT, maximumVertices );
290  glProgramParameteriEXT( programNumber, GL_GEOMETRY_INPUT_TYPE_EXT, geomInputType );
291  glProgramParameteriEXT( programNumber, GL_GEOMETRY_OUTPUT_TYPE_EXT, geomOutputType );
292  }
293 
294  return true;
295 }
bool LoadShaderFromStrings(SHADER_TYPE aShaderType, Args &&... aArgs)
Add a shader and compile the shader sources.
Definition: shader.h:93
SHADER_TYPE
Type definition for the shader.
Definition: shader.h:44
The Cairo implementation of the graphics abstraction layer.
Definition: color4d.cpp:236
int GetAttribute(const std::string &aAttributeName) const
Get an attribute location.
Definition: shader.cpp:172
GLuint geomInputType
Output type [e.g. GL_LINES, GL_TRIANGLES, GL_QUADS etc.].
Definition: shader.h:228
void SetParameter(int aParameterNumber, float aValue) const
Set a parameter of the shader.
Definition: shader.cpp:143
bool Link()
Link the shaders.
Definition: shader.cpp:101
GLuint geomOutputType
Definition: shader.h:231
void programInfo(GLuint aProgram)
Get the shader program information.
Definition: shader.cpp:178
bool LoadShaderFromFile(SHADER_TYPE aShaderType, const std::string &aShaderSourceName)
Load one of the built-in shaders and compiles it.
Definition: shader.cpp:83
bool isShaderLinked
Is the shader linked?
Definition: shader.h:223
GLuint maximumVertices
The maximum of vertices to be generated.
Definition: shader.h:225
std::deque< GLuint > shaderNumbers
Shader number list.
Definition: shader.h:220
bool loadShaderFromStringArray(SHADER_TYPE aShaderType, const char **aArray, size_t aSize)
Compile vertex of fragment shader source code into the program.
Definition: shader.cpp:238
int AddParameter(const std::string &aParameterName)
Add a parameter to the parameter queue.
Definition: shader.cpp:130
void shaderInfo(GLuint aShader)
Get the shader information.
Definition: shader.cpp:197
void Deactivate()
Deactivate the shader and use the default OpenGL program.
Definition: shader.h:135
static std::string ReadSource(const std::string &aShaderSourceName)
Read the shader source file.
Definition: shader.cpp:216
virtual ~SHADER()
Definition: shader.cpp:55
Geometry shader.
Definition: shader.h:48
bool isProgramCreated
Flag for program creation.
Definition: shader.h:222
GLuint programNumber
Shader program number.
Definition: shader.h:221
bool active
Is any of shaders used?
Definition: shader.h:224
int PGM_BASE * aProgram
Definition: cvpcb.cpp:110
void ConfigureGeometryShader(GLuint maxVertices, GLuint geometryInputType, GLuint geometryOutputType)
Configure the geometry shader - has to be done before linking!
Definition: shader.cpp:92
std::deque< GLint > parameterLocation
Location of the parameter.
Definition: shader.h:232