kicad/common/gal/opengl/shader.cpp

296 lines
8.1 KiB
C++

/*
* This program source code file is part of KICAD, a free EDA CAD application.
*
* Copyright (C) 2012 Torsten Hueter, torstenhtr <at> gmx.de
* Copyright (C) 2012-2021 Kicad Developers, see AUTHORS.txt for contributors.
*
* Graphics Abstraction Layer (GAL) for OpenGL
*
* Shader class
*
* This program 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; either version 2
* of the License, or (at your option) any later version.
*
* This program 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. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, you may find one here:
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
* or you may search the http://www.gnu.org website for the version 2 license,
* or you may write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include <iostream>
#include <fstream>
#include <stdexcept>
#include <cstring>
#include <cassert>
#include <gal/opengl/shader.h>
#include <vector>
using namespace KIGFX;
SHADER::SHADER() :
isProgramCreated( false ),
isShaderLinked( false ),
active( false ),
maximumVertices( 4 ),
geomInputType( GL_LINES ),
geomOutputType( GL_LINES )
{
// Do not have uninitialized members:
programNumber = 0;
}
SHADER::~SHADER()
{
if( active )
Deactivate();
if( isProgramCreated )
{
if( glIsShader )
{
// Delete the shaders and the program
for( std::deque<GLuint>::iterator it = shaderNumbers.begin(); it != shaderNumbers.end();
++it )
{
GLuint shader = *it;
if( glIsShader( shader ) )
{
glDetachShader( programNumber, shader );
glDeleteShader( shader );
}
}
glDeleteProgram( programNumber );
}
}
}
bool SHADER::LoadShaderFromFile( SHADER_TYPE aShaderType, const std::string& aShaderSourceName )
{
// Load shader sources
const std::string shaderSource = ReadSource( aShaderSourceName );
return LoadShaderFromStrings( aShaderType, shaderSource );
}
void SHADER::ConfigureGeometryShader( GLuint maxVertices, GLuint geometryInputType,
GLuint geometryOutputType )
{
maximumVertices = maxVertices;
geomInputType = geometryInputType;
geomOutputType = geometryOutputType;
}
bool SHADER::Link()
{
// Shader linking
glLinkProgram( programNumber );
programInfo( programNumber );
// Check the Link state
GLint tmp;
glGetProgramiv( programNumber, GL_LINK_STATUS, &tmp );
isShaderLinked = !!tmp;
#ifdef DEBUG
if( !isShaderLinked )
{
int maxLength;
glGetProgramiv( programNumber, GL_INFO_LOG_LENGTH, &maxLength );
maxLength = maxLength + 1;
char* linkInfoLog = new char[maxLength];
glGetProgramInfoLog( programNumber, maxLength, &maxLength, linkInfoLog );
std::cerr << "Shader linking error:" << std::endl;
std::cerr << linkInfoLog;
delete[] linkInfoLog;
}
#endif /* DEBUG */
return isShaderLinked;
}
int SHADER::AddParameter( const std::string& aParameterName )
{
GLint location = glGetUniformLocation( programNumber, aParameterName.c_str() );
if( location >= 0 )
parameterLocation.push_back( location );
else
throw std::runtime_error( "Could not find shader uniform: " + aParameterName );
return parameterLocation.size() - 1;
}
void SHADER::SetParameter( int parameterNumber, float value ) const
{
assert( (unsigned) parameterNumber < parameterLocation.size() );
glUniform1f( parameterLocation[parameterNumber], value );
}
void SHADER::SetParameter( int parameterNumber, int value ) const
{
assert( (unsigned) parameterNumber < parameterLocation.size() );
glUniform1i( parameterLocation[parameterNumber], value );
}
void SHADER::SetParameter( int parameterNumber, float f0, float f1, float f2, float f3 ) const
{
assert( (unsigned) parameterNumber < parameterLocation.size() );
float arr[4] = { f0, f1, f2, f3 };
glUniform4fv( parameterLocation[parameterNumber], 1, arr );
}
void SHADER::SetParameter( int aParameterNumber, const VECTOR2D& aValue ) const
{
assert( (unsigned) aParameterNumber < parameterLocation.size() );
glUniform2f( parameterLocation[aParameterNumber], aValue.x, aValue.y );
}
int SHADER::GetAttribute( const std::string& aAttributeName ) const
{
return glGetAttribLocation( programNumber, aAttributeName.c_str() );
}
void SHADER::programInfo( GLuint aProgram )
{
GLint glInfoLogLength = 0;
GLint writtenChars = 0;
// Get the length of the info string
glGetProgramiv( aProgram, GL_INFO_LOG_LENGTH, &glInfoLogLength );
// Print the information
if( glInfoLogLength > 2 )
{
GLchar* glInfoLog = new GLchar[glInfoLogLength];
glGetProgramInfoLog( aProgram, glInfoLogLength, &writtenChars, glInfoLog );
delete[] glInfoLog;
}
}
void SHADER::shaderInfo( GLuint aShader )
{
GLint glInfoLogLength = 0;
GLint writtenChars = 0;
// Get the length of the info string
glGetShaderiv( aShader, GL_INFO_LOG_LENGTH, &glInfoLogLength );
// Print the information
if( glInfoLogLength > 2 )
{
GLchar* glInfoLog = new GLchar[glInfoLogLength];
glGetShaderInfoLog( aShader, glInfoLogLength, &writtenChars, glInfoLog );
delete[] glInfoLog;
}
}
std::string SHADER::ReadSource( const std::string& aShaderSourceName )
{
// Open the shader source for reading
std::ifstream inputFile( aShaderSourceName.c_str(), std::ifstream::in );
std::string shaderSource;
if( !inputFile )
throw std::runtime_error( "Can't read the shader source: " + aShaderSourceName );
std::string shaderSourceLine;
// Read all lines from the text file
while( getline( inputFile, shaderSourceLine ) )
{
shaderSource += shaderSourceLine;
shaderSource += "\n";
}
return shaderSource;
}
bool SHADER::loadShaderFromStringArray( SHADER_TYPE aShaderType, const char** aArray, size_t aSize )
{
assert( !isShaderLinked );
// Create the program
if( !isProgramCreated )
{
programNumber = glCreateProgram();
isProgramCreated = true;
}
// Create a shader
GLuint shaderNumber = glCreateShader( aShaderType );
shaderNumbers.push_back( shaderNumber );
// Get the program info
programInfo( programNumber );
// Attach the sources
glShaderSource( shaderNumber, aSize, (const GLchar**) aArray, nullptr );
programInfo( programNumber );
// Compile and attach shader to the program
glCompileShader( shaderNumber );
GLint status;
glGetShaderiv( shaderNumber, GL_COMPILE_STATUS, &status );
if( status != GL_TRUE )
{
shaderInfo( shaderNumber );
GLint maxLength = 0;
glGetShaderiv( shaderNumber, GL_INFO_LOG_LENGTH, &maxLength );
// The maxLength includes the NULL character
std::vector<GLchar> errorLog( (size_t) maxLength );
glGetShaderInfoLog( shaderNumber, maxLength, &maxLength, &errorLog[0] );
// Provide the infolog in whatever manor you deem best.
// Exit with failure.
glDeleteShader( shaderNumber ); // Don't leak the shader.
throw std::runtime_error( &errorLog[0] );
}
glAttachShader( programNumber, shaderNumber );
programInfo( programNumber );
// Special handling for the geometry shader
if( aShaderType == SHADER_TYPE_GEOMETRY )
{
glProgramParameteriEXT( programNumber, GL_GEOMETRY_VERTICES_OUT_EXT, maximumVertices );
glProgramParameteriEXT( programNumber, GL_GEOMETRY_INPUT_TYPE_EXT, geomInputType );
glProgramParameteriEXT( programNumber, GL_GEOMETRY_OUTPUT_TYPE_EXT, geomOutputType );
}
return true;
}