com.metsci.glimpse.jogamp.opengl.util.awt.text.ShaderLoader Maven / Gradle / Ivy
/*
* Copyright 2012 JogAmp Community. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are
* permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* The views and conclusions contained in the software and documentation are those of the
* authors and should not be interpreted as representing official policies, either expressed
* or implied, of JogAmp Community.
*/
package com.metsci.glimpse.jogamp.opengl.util.awt.text;
import com.jogamp.opengl.GL2ES2;
import com.jogamp.opengl.GLException;
import com.jogamp.opengl.util.glsl.ShaderUtil;
/**
* Utility to load shaders from files, URLs, and strings.
*
*
* {@code ShaderLoader} is a simple utility for loading shaders. It takes shaders directly as
* strings. It will create and compile the shaders, and link them together into a program. Both
* compiling and linking are verified. If a problem occurs a {@link GLException} is thrown with
* the appropriate log attached.
*
*
* Note it is highly recommended that if the developer passes the strings directly to {@code
* ShaderLoader} that they contain newlines. That way if any errors do occur their line numbers
* will be reported correctly. This means that if the shader is to be embedded in Java code, a
* "\n" should be appended to every line.
*/
/*@VisibleForTesting*/
/*@ThreadSafe*/
public final class ShaderLoader
{
/**
* Prevents instantiation.
*/
private ShaderLoader( )
{
// empty
}
/**
* Checks that a shader was compiled correctly.
*
* @param gl OpenGL context, assumed not null
* @param shader OpenGL handle to a shader
* @return True if shader was compiled without errors
*/
public static boolean isShaderCompiled( /*@Nonnull*/ final GL2ES2 gl, final int shader )
{
return ShaderUtil.isShaderStatusValid( gl, shader, GL2ES2.GL_COMPILE_STATUS, null );
}
/**
* Checks that a shader program was linked successfully.
*
* @param gl OpenGL context, assumed not null
* @param program OpenGL handle to a shader program
* @return True if program was linked successfully
*/
public static boolean isProgramLinked( /*@Nonnull*/ final GL2ES2 gl, final int program )
{
return ShaderUtil.isProgramStatusValid( gl, program, GL2ES2.GL_LINK_STATUS );
}
/**
* Checks that a shader program was validated successfully.
*
* @param gl OpenGL context, assumed not null
* @param program OpenGL handle to a shader program
* @return True if program was validated successfully
*/
public static boolean isProgramValidated( /*@Nonnull*/ final GL2ES2 gl, final int program )
{
return ShaderUtil.isProgramStatusValid( gl, program, GL2ES2.GL_VALIDATE_STATUS );
}
/**
* Loads a shader program from a pair of strings.
*
* @param gl Current OpenGL context
* @param vss Vertex shader source
* @param fss Fragment shader source
* @return OpenGL handle to the shader program, not negative
* @throws NullPointerException if context or either source is null
* @throws IllegalArgumentException if either source is empty
* @throws GLException if program did not compile, link, or validate successfully
*/
/*@Nonnegative*/
public static int loadProgram( /*@Nonnull*/ final GL2ES2 gl, /*@Nonnull*/ final String vss, /*@Nonnull*/ final String fss )
{
Check.notNull( gl, "GL cannot be null" );
Check.notNull( vss, "Vertex shader source cannot be null" );
Check.notNull( fss, "Fragment shader source cannot be null" );
Check.argument( !vss.isEmpty( ), "Vertex shader source cannot be empty" );
Check.argument( !fss.isEmpty( ), "Fragment shader source cannot be empty" );
// Create the shaders
final int vs = loadShader( gl, vss, GL2ES2.GL_VERTEX_SHADER );
final int fs = loadShader( gl, fss, GL2ES2.GL_FRAGMENT_SHADER );
// Create a program and attach the shaders
final int program = gl.glCreateProgram( );
gl.glAttachShader( program, vs );
gl.glAttachShader( program, fs );
// Link the program
gl.glLinkProgram( program );
if ( !isProgramLinked( gl, program ) )
{
final String log = ShaderUtil.getProgramInfoLog( gl, program );
throw new GLException( log );
}
// Clean up the shaders
gl.glDeleteShader( vs );
gl.glDeleteShader( fs );
return program;
}
/**
* Loads a shader from a string.
*
* @param gl Current OpenGL context, assumed not null
* @param source Source code of the shader as one long string, assumed not null or empty
* @param type Type of shader, assumed valid
* @return OpenGL handle to the shader, not negative
* @throws GLException if a GLSL-capable context is not active or could not compile shader
*/
/*@Nonnegative*/
private static int loadShader( /*@Nonnull*/ final GL2ES2 gl, /*@Nonnull*/ final String source, final int type )
{
// Create and read source
final int shader = gl.glCreateShader( type );
gl.glShaderSource( shader, // shader handle
1, // number of strings
new String[] { source }, // array of strings
null ); // lengths of strings
// Compile
gl.glCompileShader( shader );
if ( !isShaderCompiled( gl, shader ) )
{
final String log = ShaderUtil.getShaderInfoLog( gl, shader );
throw new GLException( log );
}
return shader;
}
}