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diff --git a/www/j3d1_4/shaders.html b/www/j3d1_4/shaders.html index 5a3d6e0..4cdc828 100644 --- a/www/j3d1_4/shaders.html +++ b/www/j3d1_4/shaders.html @@ -3,182 +3,12 @@ <head> <meta content="text/html; charset=ISO-8859-1" http-equiv="content-type"> - <title>Java 3D 1.4: Programmable Shaders</title> + <title>Obsolete Page</title> </head> <body> -<h2>Java 3D<sup><font size="-2">TM</font></sup> 1.4: -Programmable Shaders</h2> -<p>This is the latest draft of the proposed Java 3D<sup><font - size="-2">TM</font></sup> -1.4 API changes for programmable shaders.<br> -</p> -<p>We have created a thread on the Java 3D discussion forum for -discussing <a - href="http://www.javadesktop.org/forums/thread.jspa?threadID=5056" - target="_blank">Java 3D Programmable Shaders</a>. Feel free to -post your comments on our ideas, or post some ideas of your own. -</p> -<h4>Class Hierarchy for Shader Objects</h4> -<p>The proposed class hierarchy for programmable shaders -in Java 3D is:</p> -<ul> - <li>Abstract shader base classes:</li> - <ul> - <pre>public abstract class ShaderProgram extends NodeComponent<br>public abstract class Shader extends NodeComponent<br></pre> - </ul> - <li>Concrete GLSL shader classes:</li> - <ul> - <pre>public class GLSLShaderProgram extends ShaderProgram<br> method: {add/remove/get}Shader(GLSLShader) // set of shader objs<br> method: {add/remove}ErrorListener(GLSLErrorListener)<br> method: validate(Canvas3D) ???<br><br>public abstract class GLSLShader extends Shader<br> public class GLSLVertexShader extends GLSLShader<br> method: set/getShaderSource(String)<br> method: validate(Canvas3D) ???<br> public class GLSLFragmentShader extends GLSLShader<br> method: set/getShaderSource(String)<br> method: validate(Canvas3D) ???<br></pre> - </ul> - <li>Concrete Cg shader classes:</li> - <ul> - <pre>public class CgShaderProgram extends ShaderProgram<br> method: {set/get}VertexShader(CgVertexShader)<br> method: {set/get}FragmentShader(CgFramentShader)<br> method: {add/remove}ErrorListener(CgErrorListener)<br> method: validate(Canvas3D) ???<br><br>public abstract class CgShader extends Shader<br> public class CgVertexShader extends CgShader<br> method: set/getShaderSource(String)<br> method: validate(Canvas3D) ???<br> public class CgFragmentShader extends CgShader<br> method: set/getShaderSource(String)<br> method: validate(Canvas3D) ???<br></pre> - </ul> - <li>New ShaderAppearance class:</li> - <ul> - <pre>public class ShaderAppearance extends Appearance<br> method: set/getShaderProgram(ShaderProgram)<br> method: set/getShaderAttributeSet(ShaderAttributeSet)<br></pre> - </ul> - <li>New ShaderAttributeSet class:</li> - <ul> - <pre>public class ShaderAttributeSet extends NodeComponent<br> method: put/get(ShaderAttribute)<br> ...<br></pre> - </ul> -</ul> -<p>Click on the following link for a current look at the <a - href="http://download.java.net/media/java3d/javadoc/1.4.0-latest/index.html">javadoc-generated -API definitions</a> for the proposed 1.4 API. -</p> -<h4>Example Usage</h4> -<p>This is an example code excerpt showing how one might use the new -programmable shader API in a Java 3D program. -</p> -<ul> - <pre>String vertexShaderFile = "my-vertex-shader-file-name";<br>String fragmentShaderFile = "my-fragment-shader-file-name";<br>String vertexShaderSource;<br>String fragmentShaderSource;<br><br>// Read GLSL vertex and fragment shader source code from text files<br>vertexShaderSource = StringIO.readFully(vertexShaderFile);<br>fragmentShaderSource = StringIO.readFully(fragmentShaderSource);<br><br>// Create GLSL vertex and fragment shader objects using the given source code<br>GLSLVertexShader vertexShader = new GLSLVertexShader(vertexShaderSource);<br>GLSLFragmentShader fragmentShader = new GLSLFragmentShader(fragmentShaderSource);<br><br>// Create the GLSL shader program object and attach the vertex and<br>// fragment shader objects; add an error listener<br>GLSLShaderProgram shaderProgram = new GLSLShaderProgram();<br>shaderProgram.setVertexShader(vertexShader);<br>shaderProgram.setFragmentShader(fragmentShader);<br>shaderProgram.addErrorListener(myGLSLErrorListener);<br><br>// Use GLSL shader program object in appearance<br>shaderAppearance.setShaderProgram(shaderProgram);<br></pre> -</ul> -<h4>Shader Parameters</h4> -<p>Programmable shaders define two types of parameters: uniform and -varying. As the names imply, uniform parameters are constant (within a -primitive), while varying parameters can vary on per-vertex or -per-fragment basis. -</p> -<ol> - <li><b>Uniform parameters</b> (attributes) are those parameters whose -value is constant during the rendering of a primitive. Their values -may change from primitive to primitive, but are constant for each -vertex (for vertex shaders) or fragment (for fragment shaders) of a -single primitive. Examples of uniform parameters include a -transformation matrix, a texture map, lights, lookup tables, -etc.<br> - <br> -We have created a new ShaderAttributeSet for allowing applications to -specify uniform shader attributes. There are two ways in which values -can be specified for uniform attributes: explicitly, by providing a -value; and implicitly, by defining a binding between a Java 3D system -attribute and a uniform attribute. This functionality is provided by -two subclasses of ShaderAttribute: ShaderAttributeObject, which is -used to specify explicitly defined attributes; and -ShaderAttributeBinding, which is used to specify implicitly defined, -automatically tracked attributes. See the javadoc for the new <a - href="http://download.java.net/media/java3d/javadoc/1.4.0-latest/javax/media/j3d/ShaderAttributeSet.html">ShaderAttributeSet</a> -and <a - href="http://download.java.net/media/java3d/javadoc/1.4.0-latest/javax/media/j3d/ShaderAttribute.html">ShaderAttribute</a> -classes for more details.<br> - <br> - <b>Issues</b><br> - <ul> - <li>Should j3dAttrName be specified as a type-safe enum or object -instead of a String? - <ul> - <font color="gray"><li>No; we will use a String</li> - </font> - </ul> - </li> - <li>How do we handle passing arrays to the shader, especially for -system parameters such as lights? One possibility is: - <ul> -"var" - scalar variable "var"<br> -"arr[0]" - array element 0 of "arr"<br> -"arr[1,3]" - subarray composed of elements 1 through 3 of "arr"<br> -"arr[]" - entire array "arr"<br> - </ul> -Alternatively, an object with a string or type-safe enum, a state -(scalar, array element, subarray, or entire array), and indices (as -needed). - <ul> - <font color="gray"><li>TBD, but since they will be String -objects, we will probably -do something like the first suggestion</li> - </font> - </ul> - </li> - </ul> - <br> - <b>Automatic variables</b><br> -Depending on the shading language (and profile) being used, several -Java 3D state attributes are automatically made available to the -shader program as pre-defined uniform attributes. The application -doesn't need to do anything to pass these attributes in to the shader -program. The implementation of each shader language (e.g., Cg, GLSL) -defines its own mapping from Java 3D attribute to uniform -variable name.<br> - <br> -A partial list of Java 3D attributes that are mapped to shader -attributes follows: </li> - <br> - <table style="text-align: left;" border="1" cellspacing="2" - cellpadding="2"> - <tbody> - <tr> - <td style="vertical-align: top; text-decoration: underline;">Java 3D -Attribute<br> - </td> - <td style="vertical-align: top; text-decoration: underline;">Cg -shader variable<br> - </td> - <td style="vertical-align: top; text-decoration: underline;">GLSL -shader variable<br> - </td> - </tr> - <tr> - <td style="vertical-align: top;">ModelViewProjection<br> - </td> - <td style="vertical-align: top;">glstate.matrix.mvp<br> - </td> - <td style="vertical-align: top;">gl_ModelViewProjectionMatrix<br> - </td> - </tr> - <tr> - <td style="vertical-align: top;">Light[<i>n</i>] pos<br> - </td> - <td style="vertical-align: top;">glstate.light[<i>n</i>].position - </td> - <td style="vertical-align: top;">gl_LightSource[<i>n</i>].position - </td> - </tr> - <tr> - <td style="vertical-align: top;">...<br> - </td> - <td style="vertical-align: top;">...<br> - </td> - <td style="vertical-align: top;">...<br> - </td> - </tr> - </tbody> - </table> - <br> - <li><b>Varying parameters</b> are those parameters that are specified -as per-vertex attributes. They are are interpolated across a primitive -similarly to colors and texture coordinates in the fixed function -pipeline.<br> - <br> -We need additional API to allow applications to pass in per-vertex -varying parameters...<br> -TODO: Finish this...<br> - </li> -</ol> -<p>TODO: more info here. -</p> -<p><font color="gray">Page last updated — -$Date$ -</font></p> +<h2>Obsolete Page</h2> +<p>This page is obsolete. Click <a + href="http://wiki.java.net/bin/view/Javadesktop/Java3DRoadmap">here</a> +to go the Java 3D Roadmap page of the Java 3D Wiki.</p> </body> </html> |