我不确定此代码中的问题是什么，但是当我尝试从摄像机视图中绘制远离（最后4行）的立方体线而不是对象消失时。但是，我能够绘制多维数据集的8条边线。
立方体的线（点）如下。只有前8行（16分）显示，但其余4行（8分）我无法添加到立方体中。
vec4(-0.5, -0.5, 1.5, 1.0),//1
vec4(-0.5, 0.5, 1.5, 1.0),//2
vec4(-0.5, -0.5, 1.5, 1.0),//1
vec4(0.5, -0.5, 1.5, 1.0),//4
vec4(-0.5, -0.5, 1.5, 1.0),//1
vec4(-0.5, -0.5, 0.5, 1.0),//5
vec4(-0.5, 0.5, 1.5, 1.0),//2
vec4(0.5, 0.5, 1.5, 1.0),//3
vec4(-0.5, 0.5, 1.5, 1.0),//2
vec4(-0.5, 0.5, 0.5, 1.0),//6
vec4(0.5, 0.5, 1.5, 1.0),//3
vec4(0.5, -0.5, 1.5, 1.0),//4
vec4(0.5, 0.5, 1.5, 1.0),//3
vec4(0.5, 0.5, 0.5, 1.0),//7
vec4(0.5, -0.5, 1.5, 1.0),//4
vec4( 0.5, -0.5, 0.5, 1.0) //8
/*
vec4(-0.5, -0.5, 0.5, 1.0),//5
vec4(-0.5, 0.5, 0.5, 1.0),//6
vec4(-0.5, -0.5, 0.5, 1.0),//5
vec4( 0.5, -0.5, 0.5, 1.0) //8
vec4(-0.5, 0.5, 0.5, 1.0),//6
vec4(0.5, 0.5, 0.5, 1.0),//7
vec4(0.5, 0.5, 0.5, 1.0),//7
vec4( 0.5, -0.5, 0.5, 1.0) //8
*/
非常感谢任何帮助。
以下是代码：
<script id="vertex-shader" type="x-shader/x-vertex">
attribute vec4 vPosition;
attribute vec4 vColor;
varying vec4 fColor;
uniform mat4 modelViewMatrix;
uniform mat4 projectionMatrix;
void main()
{
gl_Position = projectionMatrix*modelViewMatrix*vPosition;
fColor = vColor;
}
</script>
<script id="fragment-shader" type="x-shader/x-fragment">
precision mediump float;
varying vec4 fColor;
void
main()
{
gl_FragColor = fColor;
}
</script>
var canvas;
var gl;
var NumVertices = 24;
var vertices = [
vec4(-0.5, -0.5, 1.5, 1.0),//1
vec4(-0.5, 0.5, 1.5, 1.0),//2
vec4(-0.5, -0.5, 1.5, 1.0),//1
vec4(0.5, -0.5, 1.5, 1.0),//4
vec4(-0.5, -0.5, 1.5, 1.0),//1
vec4(-0.5, -0.5, 0.5, 1.0),//5
vec4(-0.5, 0.5, 1.5, 1.0),//2
vec4(0.5, 0.5, 1.5, 1.0),//3
vec4(-0.5, 0.5, 1.5, 1.0),//2
vec4(-0.5, 0.5, 0.5, 1.0),//6
vec4(0.5, 0.5, 1.5, 1.0),//3
vec4(0.5, -0.5, 1.5, 1.0),//4
vec4(0.5, 0.5, 1.5, 1.0),//3
vec4(0.5, 0.5, 0.5, 1.0),//7
vec4(0.5, -0.5, 1.5, 1.0),//4
vec4( 0.5, -0.5, 0.5, 1.0) //8
/*
vec4(-0.5, -0.5, 0.5, 1.0),//5
vec4(-0.5, 0.5, 0.5, 1.0),//6
vec4(-0.5, -0.5, 0.5, 1.0),//5
vec4( 0.5, -0.5, 0.5, 1.0) //8
vec4(-0.5, 0.5, 0.5, 1.0),//6
vec4(0.5, 0.5, 0.5, 1.0),//7
vec4(0.5, 0.5, 0.5, 1.0),//7
vec4( 0.5, -0.5, 0.5, 1.0) //8
*/
];
var vertexColors = [
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
/*
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
*/
];
var near = 0.3;
var far = 10.0;
var radius = 4.0;
var theta = 0.0;
var phi = 0.0;
var dr = 5.0 * Math.PI/180.0;
var fovy = 90.0; // Field-of-view in Y direction angle (in degrees)
var aspect; // Viewport aspect ratio
var modelViewMatrix, projectionMatrix;
var modelViewMatrixLoc, projectionMatrixLoc;
var eye;
const at = vec3(0.0, 0.0, 0.0);
const up = vec3(0.0, 1.0, 0.0);
var program;
var program_originline;
var cBuffer;
var vColor;
var vBuffer;
var vPosition;
var l_vBuffer;
var l_vPosition;
var l_cBuffer;
var l_vColor;
window.onload = function init() {
canvas = document.getElementById( "gl-canvas" );
gl = WebGLUtils.setupWebGL( canvas );
if ( !gl ) { alert( "WebGL isn't available" ); }
gl.viewport( 0, 0, canvas.width, canvas.height );
aspect = canvas.width/canvas.height;
gl.clearColor( 0.0, 0.0, 0.0, 1.0 );
gl.enable(gl.DEPTH_TEST);
// Load shaders and initialize attribute buffers
program_originline = initShaders( gl, "vertex-shader", "fragment-shader" );
program = initShaders( gl, "vertex-shader", "fragment-shader" );
//CUBE Buffers
cBuffer = gl.createBuffer();
gl.bindBuffer( gl.ARRAY_BUFFER, cBuffer );
//gl.bufferData( gl.ARRAY_BUFFER, flatten(colorsArray), gl.STATIC_DRAW );
gl.bufferData( gl.ARRAY_BUFFER, flatten(vertexColors), gl.STATIC_DRAW );
vColor = gl.getAttribLocation( program, "vColor" );
//gl.vertexAttribPointer( vColor, 4, gl.FLOAT, false, 0, 0 );
//gl.enableVertexAttribArray( vColor);
vBuffer = gl.createBuffer();
gl.bindBuffer( gl.ARRAY_BUFFER, vBuffer );
//gl.bufferData( gl.ARRAY_BUFFER, flatten(pointsArray), gl.STATIC_DRAW );
gl.bufferData( gl.ARRAY_BUFFER, flatten(vertices), gl.STATIC_DRAW );
vPosition = gl.getAttribLocation( program, "vPosition" );
//Static Line
var l_vertices = [
vec4(0.0, 0.0, 0.0, 1.0),
vec4(5.0, 0.0, 0.0, 1.0),
vec4(0.0, 0.0, 0.0, 1.0),
vec4(0.0, 5.0, 0.0, 1.0),
vec4(0.0, 0.0, 0.0, 1.0),
vec4(0.0, 0.0, 5.0, 1.0),
vec4(0.0, 0.0, 0.0, 1.0),
vec4(-5.0, 0.0, 0.0, 1.0),
vec4(0.0, 0.0, 0.0, 1.0),
vec4(0.0, -5.0, 0.0, 1.0),
vec4(0.0, 0.0, 0.0, 1.0),
vec4(0.0, 0.0, -5.0, 1.0),
];
// Load the data into the GPU
l_vBuffer = gl.createBuffer();
gl.bindBuffer( gl.ARRAY_BUFFER, l_vBuffer );
gl.bufferData( gl.ARRAY_BUFFER, flatten(l_vertices), gl.STATIC_DRAW );
// Associate out shader variables with our data buffer
l_vPosition = gl.getAttribLocation( program_originline, "vPosition" );
var l_colors = [
vec4(1.0, 1.0, 0.0, 1.0),
vec4(1.0, 1.0, 0.0, 1.0),
vec4(1.0, 1.0, 0.0, 1.0),
vec4(1.0, 1.0, 0.0, 1.0),
vec4(1.0, 1.0, 0.0, 1.0),
vec4(1.0, 1.0, 0.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
];
l_cBuffer = gl.createBuffer();
gl.bindBuffer( gl.ARRAY_BUFFER, l_cBuffer );
gl.bufferData( gl.ARRAY_BUFFER, flatten(l_colors), gl.STATIC_DRAW );
l_vColor = gl.getAttribLocation( program_originline, "vColor" );
// buttons for viewing parameters
document.getElementById("Button1").onclick = function(){near *= 1.1; far *= 1.1;};
document.getElementById("Button2").onclick = function(){near *= 0.9; far *= 0.9;};
document.getElementById("Button3").onclick = function(){radius *= 2.0;};
document.getElementById("Button4").onclick = function(){radius *= 0.5;};
document.getElementById("Button5").onclick = function(){theta += dr;};
document.getElementById("Button6").onclick = function(){theta -= dr;};
document.getElementById("Button7").onclick = function(){phi += dr;};
document.getElementById("Button8").onclick = function(){phi -= dr;};
render();
}
var render = function(){
gl.clear( gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
//LINE PROGRAM
gl.useProgram( program_originline );
gl.enableVertexAttribArray( l_vPosition );
gl.bindBuffer( gl.ARRAY_BUFFER, l_vBuffer );
gl.vertexAttribPointer( l_vPosition, 4, gl.FLOAT, false, 0, 0 );
gl.enableVertexAttribArray( l_vColor );
gl.bindBuffer( gl.ARRAY_BUFFER, l_cBuffer );
gl.vertexAttribPointer( l_vColor, 4, gl.FLOAT, false, 0, 0 );
gl.drawArrays( gl.LINES, 0, 12);
modelViewMatrixLoc = gl.getUniformLocation( program_originline, "modelViewMatrix" );
projectionMatrixLoc = gl.getUniformLocation( program_originline, "projectionMatrix" );
eye = vec3(radius*Math.sin(theta)*Math.cos(phi),
radius*Math.sin(theta)*Math.sin(phi), radius*Math.cos(theta));
modelViewMatrix = lookAt(eye, at , up);
projectionMatrix = perspective(fovy, aspect, near, far);
gl.uniformMatrix4fv( modelViewMatrixLoc, false, flatten(modelViewMatrix) );
gl.uniformMatrix4fv( projectionMatrixLoc, false, flatten(projectionMatrix) );
//CUBE PROGRAM
gl.useProgram( program );
gl.enableVertexAttribArray( vPosition );
gl.bindBuffer( gl.ARRAY_BUFFER, vBuffer );
gl.vertexAttribPointer( vPosition, 4, gl.FLOAT, false, 0, 0 );
gl.enableVertexAttribArray( vColor);
gl.bindBuffer( gl.ARRAY_BUFFER, cBuffer );
gl.vertexAttribPointer( vColor, 4, gl.FLOAT, false, 0, 0 );
gl.drawArrays( gl.LINES, 0, 18 );
modelViewMatrixLoc = gl.getUniformLocation( program, "modelViewMatrix" );
projectionMatrixLoc = gl.getUniformLocation( program, "projectionMatrix" );
eye = vec3(radius*Math.sin(theta)*Math.cos(phi),radius*Math.sin(theta)*Math.sin(phi), radius*Math.cos(theta));
modelViewMatrix = lookAt(eye, at , up);
projectionMatrix = perspective(fovy, aspect, near, far);
gl.uniformMatrix4fv( modelViewMatrixLoc, false, flatten(modelViewMatrix) );
gl.uniformMatrix4fv( projectionMatrixLoc, false, flatten(projectionMatrix) );
requestAnimFrame(render);
}
答案 0 :(得分：3)
您必须将drawArrays的最后一个参数从18更新为24（因为每个立方体有12行，每行有2个顶点）。
gl.drawArrays( gl.LINES, 0, 24 );
当然记得要取消注释vertices和vertexColors数组中的行（并确保数组中没有任何遗漏或额外的逗号）。
在我完成所有必要的修复后，这是您的代码：
var canvas;
var gl;
var NumVertices = 24;
var vertices = [
vec4(-0.5, -0.5, 1.5, 1.0),//1
vec4(-0.5, 0.5, 1.5, 1.0),//2
vec4(-0.5, -0.5, 1.5, 1.0),//1
vec4(0.5, -0.5, 1.5, 1.0),//4
vec4(-0.5, -0.5, 1.5, 1.0),//1
vec4(-0.5, -0.5, 0.5, 1.0),//5
vec4(-0.5, 0.5, 1.5, 1.0),//2
vec4(0.5, 0.5, 1.5, 1.0),//3
vec4(-0.5, 0.5, 1.5, 1.0),//2
vec4(-0.5, 0.5, 0.5, 1.0),//6
vec4(0.5, 0.5, 1.5, 1.0),//3
vec4(0.5, -0.5, 1.5, 1.0),//4
vec4(0.5, 0.5, 1.5, 1.0),//3
vec4(0.5, 0.5, 0.5, 1.0),//7
vec4(0.5, -0.5, 1.5, 1.0),//4
vec4( 0.5, -0.5, 0.5, 1.0), //8
vec4(-0.5, -0.5, 0.5, 1.0),//5
vec4(-0.5, 0.5, 0.5, 1.0),//6
vec4(-0.5, -0.5, 0.5, 1.0),//5
vec4( 0.5, -0.5, 0.5, 1.0), //8
vec4(-0.5, 0.5, 0.5, 1.0),//6
vec4(0.5, 0.5, 0.5, 1.0),//7
vec4(0.5, 0.5, 0.5, 1.0),//7
vec4( 0.5, -0.5, 0.5, 1.0) //8
];
var vertexColors = [
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
vec4( 1.0, 0.0, 0.0, 1.0 ), // red
];
var near = 0.3;
var far = 10.0;
var radius = 4.0;
var theta = 0.0;
var phi = 0.0;
var dr = 5.0 * Math.PI/180.0;
var fovy = 90.0; // Field-of-view in Y direction angle (in degrees)
var aspect; // Viewport aspect ratio
var modelViewMatrix, projectionMatrix;
var modelViewMatrixLoc, projectionMatrixLoc;
var eye;
const at = vec3(0.0, 0.0, 0.0);
const up = vec3(0.0, 1.0, 0.0);
var program;
var program_originline;
var cBuffer;
var vColor;
var vBuffer;
var vPosition;
var l_vBuffer;
var l_vPosition;
var l_cBuffer;
var l_vColor;
window.onload = function init() {
canvas = document.getElementById( "gl-canvas" );
gl = WebGLUtils.setupWebGL( canvas );
if ( !gl ) { alert( "WebGL isn't available" ); }
gl.viewport( 0, 0, canvas.width, canvas.height );
aspect = canvas.width/canvas.height;
gl.clearColor( 0.0, 0.0, 0.0, 1.0 );
gl.enable(gl.DEPTH_TEST);
// Load shaders and initialize attribute buffers
program_originline = initShaders( gl, "vertex-shader", "fragment-shader" );
program = initShaders( gl, "vertex-shader", "fragment-shader" );
//CUBE Buffers
cBuffer = gl.createBuffer();
gl.bindBuffer( gl.ARRAY_BUFFER, cBuffer );
//gl.bufferData( gl.ARRAY_BUFFER, flatten(colorsArray), gl.STATIC_DRAW );
gl.bufferData( gl.ARRAY_BUFFER, flatten(vertexColors), gl.STATIC_DRAW );
vColor = gl.getAttribLocation( program, "vColor" );
//gl.vertexAttribPointer( vColor, 4, gl.FLOAT, false, 0, 0 );
//gl.enableVertexAttribArray( vColor);
vBuffer = gl.createBuffer();
gl.bindBuffer( gl.ARRAY_BUFFER, vBuffer );
//gl.bufferData( gl.ARRAY_BUFFER, flatten(pointsArray), gl.STATIC_DRAW );
gl.bufferData( gl.ARRAY_BUFFER, flatten(vertices), gl.STATIC_DRAW );
vPosition = gl.getAttribLocation( program, "vPosition" );
//Static Line
var l_vertices = [
vec4(0.0, 0.0, 0.0, 1.0),
vec4(5.0, 0.0, 0.0, 1.0),
vec4(0.0, 0.0, 0.0, 1.0),
vec4(0.0, 5.0, 0.0, 1.0),
vec4(0.0, 0.0, 0.0, 1.0),
vec4(0.0, 0.0, 5.0, 1.0),
vec4(0.0, 0.0, 0.0, 1.0),
vec4(-5.0, 0.0, 0.0, 1.0),
vec4(0.0, 0.0, 0.0, 1.0),
vec4(0.0, -5.0, 0.0, 1.0),
vec4(0.0, 0.0, 0.0, 1.0),
vec4(0.0, 0.0, -5.0, 1.0),
];
// Load the data into the GPU
l_vBuffer = gl.createBuffer();
gl.bindBuffer( gl.ARRAY_BUFFER, l_vBuffer );
gl.bufferData( gl.ARRAY_BUFFER, flatten(l_vertices), gl.STATIC_DRAW );
// Associate out shader variables with our data buffer
l_vPosition = gl.getAttribLocation( program_originline, "vPosition" );
var l_colors = [
vec4(1.0, 1.0, 0.0, 1.0),
vec4(1.0, 1.0, 0.0, 1.0),
vec4(1.0, 1.0, 0.0, 1.0),
vec4(1.0, 1.0, 0.0, 1.0),
vec4(1.0, 1.0, 0.0, 1.0),
vec4(1.0, 1.0, 0.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
vec4(0.0, 0.0, 1.0, 1.0),
];
l_cBuffer = gl.createBuffer();
gl.bindBuffer( gl.ARRAY_BUFFER, l_cBuffer );
gl.bufferData( gl.ARRAY_BUFFER, flatten(l_colors), gl.STATIC_DRAW );
l_vColor = gl.getAttribLocation( program_originline, "vColor" );
// buttons for viewing parameters
document.getElementById("Button1").onclick = function(){near *= 1.1; far *= 1.1;};
document.getElementById("Button2").onclick = function(){near *= 0.9; far *= 0.9;};
document.getElementById("Button3").onclick = function(){radius *= 2.0;};
document.getElementById("Button4").onclick = function(){radius *= 0.5;};
document.getElementById("Button5").onclick = function(){theta += dr;};
document.getElementById("Button6").onclick = function(){theta -= dr;};
document.getElementById("Button7").onclick = function(){phi += dr;};
document.getElementById("Button8").onclick = function(){phi -= dr;};
render();
}
var render = function(){
gl.clear( gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
//LINE PROGRAM
gl.useProgram( program_originline );
gl.enableVertexAttribArray( l_vPosition );
gl.bindBuffer( gl.ARRAY_BUFFER, l_vBuffer );
gl.vertexAttribPointer( l_vPosition, 4, gl.FLOAT, false, 0, 0 );
gl.enableVertexAttribArray( l_vColor );
gl.bindBuffer( gl.ARRAY_BUFFER, l_cBuffer );
gl.vertexAttribPointer( l_vColor, 4, gl.FLOAT, false, 0, 0 );
gl.drawArrays( gl.LINES, 0, 12);
modelViewMatrixLoc = gl.getUniformLocation( program_originline, "modelViewMatrix" );
projectionMatrixLoc = gl.getUniformLocation( program_originline, "projectionMatrix" );
eye = vec3(radius*Math.sin(theta)*Math.cos(phi),
radius*Math.sin(theta)*Math.sin(phi), radius*Math.cos(theta));
modelViewMatrix = lookAt(eye, at , up);
projectionMatrix = perspective(fovy, aspect, near, far);
gl.uniformMatrix4fv( modelViewMatrixLoc, false, flatten(modelViewMatrix) );
gl.uniformMatrix4fv( projectionMatrixLoc, false, flatten(projectionMatrix) );
//CUBE PROGRAM
gl.useProgram( program );
gl.enableVertexAttribArray( vPosition );
gl.bindBuffer( gl.ARRAY_BUFFER, vBuffer );
gl.vertexAttribPointer( vPosition, 4, gl.FLOAT, false, 0, 0 );
gl.enableVertexAttribArray( vColor);
gl.bindBuffer( gl.ARRAY_BUFFER, cBuffer );
gl.vertexAttribPointer( vColor, 4, gl.FLOAT, false, 0, 0 );
gl.drawArrays( gl.LINES, 0, 24 );
modelViewMatrixLoc = gl.getUniformLocation( program, "modelViewMatrix" );
projectionMatrixLoc = gl.getUniformLocation( program, "projectionMatrix" );
eye = vec3(radius*Math.sin(theta)*Math.cos(phi),radius*Math.sin(theta)*Math.sin(phi), radius*Math.cos(theta));
modelViewMatrix = lookAt(eye, at , up);
projectionMatrix = perspective(fovy, aspect, near, far);
gl.uniformMatrix4fv( modelViewMatrixLoc, false, flatten(modelViewMatrix) );
gl.uniformMatrix4fv( projectionMatrixLoc, false, flatten(projectionMatrix) );
requestAnimFrame(render);
}<html>
<head>
<script type="text/javascript" src="http://www.cs.unm.edu/~angel/WebGL/7E/Common/webgl-utils.js"></script>
<script type="text/javascript" src="http://www.cs.unm.edu/~angel/WebGL/7E/Common/MV.js"></script>
<script type="text/javascript" src="http://www.cs.unm.edu/~angel/WebGL/7E/Common/initShaders.js"></script>
<script id="vertex-shader" type="x-shader/x-vertex">
attribute vec4 vPosition;
attribute vec4 vColor;
varying vec4 fColor;
uniform mat4 modelViewMatrix;
uniform mat4 projectionMatrix;
void main()
{
gl_Position = projectionMatrix*modelViewMatrix*vPosition;
fColor = vColor;
}
</script>
<script id="fragment-shader" type="x-shader/x-fragment">
precision mediump float;
varying vec4 fColor;
void
main()
{
gl_FragColor = fColor;
}
</script>
</head>
<body>
<div>
<canvas id="gl-canvas" width="300" height="300"></canvas>
</div>
<div>
<button id="Button1" type="button">1</button>
<button id="Button2" type="button">2</button>
<button id="Button3" type="button">3</button>
<button id="Button4" type="button">4</button>
<button id="Button5" type="button">5</button>
<button id="Button6" type="button">6</button>
<button id="Button7" type="button">7</button>
<button id="Button8" type="button">8</button>
</div>
</body>
</html>