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@thewtex/vtk.js-esm

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Visualization Toolkit for the Web

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import macro from '../../macro.js'; import vtkOpenGLFramebuffer from './Framebuffer.js'; import vtkRenderPass from '../SceneGraph/RenderPass.js'; import vtkDataArray from '../../Common/Core/DataArray.js'; import vtkHelper from './Helper.js'; import vtkVertexArrayObject from './VertexArrayObject.js'; import { Representation } from '../Core/Property/Constants.js'; var vtkErrorMacro = macro.vtkErrorMacro; // ---------------------------------------------------------------------------- function vtkConvolution2DPass(publicAPI, model) { // Set our className model.classHierarchy.push('vtkConvolution2DPass'); publicAPI.computeKernelWeight = function computeKernelWeight(kernel) { var weight = kernel.reduce(function (prev, curr) { return prev + curr; }); return weight <= 0 ? 1 : weight; }; // handles post-processing via convolution kernel and call delegate publicAPI.traverse = function (viewNode) { if (model.deleted) { return; } // check if kernel dimension is valid if (model.kernelDimension % 2 !== 1) { vtkErrorMacro('Invalid kernel dimension! Kernel dimension must be odd (e.g. 3, 5, 7, ...).'); return; } // if no kernel is set, use the default kernel (no post-processing) if (model.kernel === null) { model.kernel = new Float32Array(model.kernelDimension); model.kernel[Math.floor(model.kernelDimension / 2)] = 1; } var kernelLength = model.kernelDimension * model.kernelDimension; if (model.kernel.length !== kernelLength) { vtkErrorMacro("The given kernel is invalid. 2D convolution kernels have to be 1D arrays with ".concat(kernelLength, " components representing the ").concat(model.kernelDimension, "x").concat(model.kernelDimension, " kernel in row-major form.")); return; } // prepare framebuffer // allocate framebuffer if needed and bind it if (model.framebuffer === null) { model.framebuffer = vtkOpenGLFramebuffer.newInstance(); } var size = viewNode.getSize(); var gl = viewNode.getContext(); if (gl === null) { // nothing to do -> no render context // traverse delegate passes -> has to be done in order for the vtk render-pipeline to work correctly model.delegates.forEach(function (val) { val.traverse(viewNode, publicAPI); }); return; } // prepare rendering if (model.VBOBuildTime.getMTime() < publicAPI.getMTime()) { model.tris.setOpenGLRenderWindow(viewNode); publicAPI.buildVertexBuffer(); } // store framebuffer bindings to restore them later model.framebuffer.setOpenGLRenderWindow(viewNode); model.framebuffer.saveCurrentBindingsAndBuffers(); var fbSize = model.framebuffer.getSize(); if (fbSize === null || fbSize[0] !== size[0] || fbSize[1] !== size[1]) { // create post-processing framebuffer if not already existing model.framebuffer.create(size[0], size[1]); model.framebuffer.populateFramebuffer(); } // bind framebuffer to re-direct the render-output of the delegate passes to the buffer model.framebuffer.bind(); // do the delegate rendering model.delegates.forEach(function (val) { val.traverse(viewNode, publicAPI); }); // now draw the convolved values model.framebuffer.restorePreviousBindingsAndBuffers(); // check if kernel dimension has changed and convolution shader needs to be re-compiled if (model.convolutionShader !== null && model.oldKernelDimension !== model.kernelDimension) { model.convolutionShader = null; model.oldKernelDimension = model.kernelDimension; } // make sure the convolution shader is ready if (model.convolutionShader === null) { model.convolutionShader = viewNode.getShaderCache().readyShaderProgramArray(['//VTK::System::Dec', 'attribute vec4 vertexDC;', 'attribute vec2 tcoordTC;', 'varying vec2 tcoord;', 'void main() { tcoord = tcoordTC; gl_Position = vertexDC; }'].join('\n'), publicAPI.getFragmentShaderCode(model.kernelDimension), ''); var program = model.convolutionShader; // prepare the vertex and triangle data for the image plane to render to model.copyVAO = vtkVertexArrayObject.newInstance(); model.copyVAO.setOpenGLRenderWindow(viewNode); model.tris.getCABO().bind(); if (!model.copyVAO.addAttributeArray(program, model.tris.getCABO(), 'vertexDC', model.tris.getCABO().getVertexOffset(), model.tris.getCABO().getStride(), gl.FLOAT, 3, gl.FALSE)) { vtkErrorMacro('Error setting vertexDC in copy shader VAO.'); } if (!model.copyVAO.addAttributeArray(program, model.tris.getCABO(), 'tcoordTC', model.tris.getCABO().getTCoordOffset(), model.tris.getCABO().getStride(), gl.FLOAT, 2, gl.FALSE)) { vtkErrorMacro('Error setting vertexDC in copy shader VAO.'); } } else { viewNode.getShaderCache().readyShaderProgram(model.convolutionShader); } gl.viewport(0, 0, size[0], size[1]); gl.scissor(0, 0, size[0], size[1]); // activate texture var tex = model.framebuffer.getColorTexture(); tex.activate(); model.convolutionShader.setUniformi('u_image', tex.getTextureUnit()); model.convolutionShader.setUniform2f('u_textureSize', tex.getWidth(), tex.getHeight()); model.convolutionShader.setUniformfv('u_kernel', model.kernel); model.convolutionShader.setUniformf('u_kernelWeight', publicAPI.computeKernelWeight(model.kernel)); // render quad gl.drawArrays(gl.TRIANGLES, 0, model.tris.getCABO().getElementCount()); tex.deactivate(); }; publicAPI.getFragmentShaderCode = function (kernelDimension) { // generate new shader code var kernelLength = kernelDimension * kernelDimension; var shaderCode = ['//VTK::System::Dec', '//VTK::Output::Dec', 'uniform sampler2D u_image;', 'uniform vec2 u_textureSize;', "uniform float u_kernel[".concat(kernelLength, "];"), 'uniform float u_kernelWeight;', 'varying vec2 tcoord;', 'void main(){', ' vec2 onePixel = vec2(1.0, 1.0) / u_textureSize;', ' vec4 colorSum =\n'].join('\n'); var halfDim = Math.floor(kernelDimension / 2); // generate sum per pixel var i = 0; for (var y = -halfDim; y <= halfDim; ++y) { for (var x = -halfDim; x <= halfDim; ++x) { shaderCode += " texture2D(u_image, tcoord + onePixel * vec2(".concat(x, ", ").concat(y, ")) * u_kernel[").concat(i, "]"); ++i; if (i !== kernelLength) { shaderCode += ' +\n'; } } } // finish code shaderCode += [';', ' gl_FragData[0] = vec4((colorSum / u_kernelWeight).rgb, texture2D(u_image, tcoord).a);', '}'].join('\n'); return shaderCode; }; // build vertices etc publicAPI.buildVertexBuffer = function () { // 4 corner points in clipping space in order (x, y, z) where z is always set to -1 // prettier-ignore var ptsArray = new Float32Array([-1, -1, -1, 1, -1, -1, -1, 1, -1, 1, 1, -1]); // 4 corresponding corner points in texture space in order (x, y) var tcoordArray = new Float32Array([0, 0, 1, 0, 0, 1, 1, 1]); // a square defined as cell relation ship in order (cell_size, v1, v2, v3, v4) var cellArray = new Uint16Array([4, 0, 1, 3, 2]); var points = vtkDataArray.newInstance({ numberOfComponents: 3, values: ptsArray }); points.setName('points'); var tcoords = vtkDataArray.newInstance({ numberOfComponents: 2, values: tcoordArray }); tcoords.setName('tcoords'); var cells = vtkDataArray.newInstance({ numberOfComponents: 1, values: cellArray }); model.tris.getCABO().createVBO(cells, 'polys', Representation.SURFACE, { points: points, tcoords: tcoords, cellOffset: 0 }); model.VBOBuildTime.modified(); }; } // ---------------------------------------------------------------------------- // Object factory // ---------------------------------------------------------------------------- var DEFAULT_VALUES = { framebuffer: null, convolutionShader: null, tris: null, kernel: [0, 0, 0, 0, 1, 0, 0, 0, 0], oldKernelDimension: 3, kernelDimension: 3 }; // ---------------------------------------------------------------------------- function extend(publicAPI, model) { var initialValues = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : {}; Object.assign(model, DEFAULT_VALUES, initialValues); // Build VTK API vtkRenderPass.extend(publicAPI, model, initialValues); model.VBOBuildTime = {}; macro.obj(model.VBOBuildTime, { mtime: 0 }); model.tris = vtkHelper.newInstance(); macro.setGet(publicAPI, model, ['kernel', 'kernelDimension']); macro.get(publicAPI, model, ['framebuffer']); // Object methods vtkConvolution2DPass(publicAPI, model); } // ---------------------------------------------------------------------------- var newInstance = macro.newInstance(extend, 'vtkConvolution2DPass'); // ---------------------------------------------------------------------------- var vtkConvolution2DPass$1 = { newInstance: newInstance, extend: extend }; export default vtkConvolution2DPass$1; export { extend, newInstance };