- Notifications
You must be signed in to change notification settings - Fork 683
/
Copy pathwebgl-3d-step5.html
629 lines (545 loc) · 16.2 KB
/
webgl-3d-step5.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
<!-- Licensed under a BSD license. See license.html for license -->
<!DOCTYPE html>
<html>
<head>
<metacharset="utf-8">
<metaname="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
<title>WebGL - 3D Step 5 - Fix Backward Triangles</title>
<linktype="text/css" href="resources/webgl-tutorials.css" rel="stylesheet" />
</head>
<body>
<divclass="description">
Drag sliders to translate, rotate, and scale.
</div>
<canvasid="canvas"></canvas>
<divid="uiContainer">
<divid="ui">
<divid="x"></div>
<divid="y"></div>
<divid="z"></div>
<divid="angleX"></div>
<divid="angleY"></div>
<divid="angleZ"></div>
<divid="scaleX"></div>
<divid="scaleY"></div>
<divid="scaleZ"></div>
</div>
</div>
</body>
<!-- vertex shader -->
<scriptid="vertex-shader-3d" type="x-shader/x-vertex">
attributevec4a_position;
attributevec4a_color;
uniformmat4u_matrix;
varyingvec4v_color;
voidmain(){
// Multiply the position by the matrix.
gl_Position=u_matrix*a_position;
// Pass the color to the fragment shader.
v_color=a_color;
}
</script>
<!-- fragment shader -->
<scriptid="fragment-shader-3d" type="x-shader/x-fragment">
precisionmediumpfloat;
// Passed in from the vertex shader.
varyingvec4v_color;
voidmain(){
gl_FragColor=v_color;
}
</script>
<!--
for most samples webgl-utils only provides shader compiling/linking and
canvas resizing because why clutter the examples with code that's the same in every sample.
See https://webglfundamentals.org/webgl/lessons/webgl-boilerplate.html
and https://webglfundamentals.org/webgl/lessons/webgl-resizing-the-canvas.html
for webgl-utils, m3, m4, and webgl-lessons-ui.
-->
<scriptsrc="resources/webgl-utils.js"></script>
<scriptsrc="resources/webgl-lessons-ui.js"></script>
<script>
"use strict";
functionmain(){
// Get A WebGL context
/** @type {HTMLCanvasElement} */
varcanvas=document.querySelector("#canvas");
vargl=canvas.getContext("webgl");
if(!gl){
return;
}
// setup GLSL program
varprogram=webglUtils.createProgramFromScripts(gl,["vertex-shader-3d","fragment-shader-3d"]);
// look up where the vertex data needs to go.
varpositionLocation=gl.getAttribLocation(program,"a_position");
varcolorLocation=gl.getAttribLocation(program,"a_color");
// lookup uniforms
varmatrixLocation=gl.getUniformLocation(program,"u_matrix");
// Create a buffer to put positions in
varpositionBuffer=gl.createBuffer();
// Bind it to ARRAY_BUFFER (think of it as ARRAY_BUFFER = positionBuffer)
gl.bindBuffer(gl.ARRAY_BUFFER,positionBuffer);
// Put geometry data into buffer
setGeometry(gl);
// Create a buffer to put colors in
varcolorBuffer=gl.createBuffer();
// Bind it to ARRAY_BUFFER (think of it as ARRAY_BUFFER = colorBuffer)
gl.bindBuffer(gl.ARRAY_BUFFER,colorBuffer);
// Put geometry data into buffer
setColors(gl);
functionradToDeg(r){
returnr*180/Math.PI;
}
functiondegToRad(d){
returnd*Math.PI/180;
}
vartranslation=[45,150,0];
varrotation=[degToRad(40),degToRad(25),degToRad(325)];
varscale=[1,1,1];
drawScene();
// Setup a ui.
webglLessonsUI.setupSlider("#x",{value: translation[0],slide: updatePosition(0),max: gl.canvas.width});
webglLessonsUI.setupSlider("#y",{value: translation[1],slide: updatePosition(1),max: gl.canvas.height});
webglLessonsUI.setupSlider("#z",{value: translation[2],slide: updatePosition(2),max: gl.canvas.height});
webglLessonsUI.setupSlider("#angleX",{value: radToDeg(rotation[0]),slide: updateRotation(0),max: 360});
webglLessonsUI.setupSlider("#angleY",{value: radToDeg(rotation[1]),slide: updateRotation(1),max: 360});
webglLessonsUI.setupSlider("#angleZ",{value: radToDeg(rotation[2]),slide: updateRotation(2),max: 360});
webglLessonsUI.setupSlider("#scaleX",{value: scale[0],slide: updateScale(0),min: -5,max: 5,step: 0.01,precision: 2});
webglLessonsUI.setupSlider("#scaleY",{value: scale[1],slide: updateScale(1),min: -5,max: 5,step: 0.01,precision: 2});
webglLessonsUI.setupSlider("#scaleZ",{value: scale[2],slide: updateScale(2),min: -5,max: 5,step: 0.01,precision: 2});
functionupdatePosition(index){
returnfunction(event,ui){
translation[index]=ui.value;
drawScene();
};
}
functionupdateRotation(index){
returnfunction(event,ui){
varangleInDegrees=ui.value;
varangleInRadians=angleInDegrees*Math.PI/180;
rotation[index]=angleInRadians;
drawScene();
};
}
functionupdateScale(index){
returnfunction(event,ui){
scale[index]=ui.value;
drawScene();
};
}
// Draw the scene.
functiondrawScene(){
webglUtils.resizeCanvasToDisplaySize(gl.canvas);
// Tell WebGL how to convert from clip space to pixels
gl.viewport(0,0,gl.canvas.width,gl.canvas.height);
// Clear the canvas.
gl.clear(gl.COLOR_BUFFER_BIT);
// Turn on culling. By default backfacing triangles
// will be culled.
gl.enable(gl.CULL_FACE);
// Tell it to use our program (pair of shaders)
gl.useProgram(program);
// Turn on the position attribute
gl.enableVertexAttribArray(positionLocation);
// Bind the position buffer.
gl.bindBuffer(gl.ARRAY_BUFFER,positionBuffer);
// Tell the position attribute how to get data out of positionBuffer (ARRAY_BUFFER)
varsize=3;// 3 components per iteration
vartype=gl.FLOAT;// the data is 32bit floats
varnormalize=false;// don't normalize the data
varstride=0;// 0 = move forward size * sizeof(type) each iteration to get the next position
varoffset=0;// start at the beginning of the buffer
gl.vertexAttribPointer(
positionLocation,size,type,normalize,stride,offset);
// Turn on the color attribute
gl.enableVertexAttribArray(colorLocation);
// Bind the color buffer.
gl.bindBuffer(gl.ARRAY_BUFFER,colorBuffer);
// Tell the attribute how to get data out of colorBuffer (ARRAY_BUFFER)
varsize=3;// 3 components per iteration
vartype=gl.UNSIGNED_BYTE;// the data is 8bit unsigned values
varnormalize=true;// normalize the data (convert from 0-255 to 0-1)
varstride=0;// 0 = move forward size * sizeof(type) each iteration to get the next position
varoffset=0;// start at the beginning of the buffer
gl.vertexAttribPointer(
colorLocation,size,type,normalize,stride,offset);
// Compute the matrices
varmatrix=m4.projection(gl.canvas.clientWidth,gl.canvas.clientHeight,400);
matrix=m4.translate(matrix,translation[0],translation[1],translation[2]);
matrix=m4.xRotate(matrix,rotation[0]);
matrix=m4.yRotate(matrix,rotation[1]);
matrix=m4.zRotate(matrix,rotation[2]);
matrix=m4.scale(matrix,scale[0],scale[1],scale[2]);
// Set the matrix.
gl.uniformMatrix4fv(matrixLocation,false,matrix);
// Draw the geometry.
varprimitiveType=gl.TRIANGLES;
varoffset=0;
varcount=16*6;
gl.drawArrays(primitiveType,offset,count);
}
}
varm4={
projection: function(width,height,depth){
// Note: This matrix flips the Y axis so 0 is at the top.
return[
2/width,0,0,0,
0,-2/height,0,0,
0,0,2/depth,0,
-1,1,0,1,
];
},
multiply: function(a,b){
vara00=a[0*4+0];
vara01=a[0*4+1];
vara02=a[0*4+2];
vara03=a[0*4+3];
vara10=a[1*4+0];
vara11=a[1*4+1];
vara12=a[1*4+2];
vara13=a[1*4+3];
vara20=a[2*4+0];
vara21=a[2*4+1];
vara22=a[2*4+2];
vara23=a[2*4+3];
vara30=a[3*4+0];
vara31=a[3*4+1];
vara32=a[3*4+2];
vara33=a[3*4+3];
varb00=b[0*4+0];
varb01=b[0*4+1];
varb02=b[0*4+2];
varb03=b[0*4+3];
varb10=b[1*4+0];
varb11=b[1*4+1];
varb12=b[1*4+2];
varb13=b[1*4+3];
varb20=b[2*4+0];
varb21=b[2*4+1];
varb22=b[2*4+2];
varb23=b[2*4+3];
varb30=b[3*4+0];
varb31=b[3*4+1];
varb32=b[3*4+2];
varb33=b[3*4+3];
return[
b00*a00+b01*a10+b02*a20+b03*a30,
b00*a01+b01*a11+b02*a21+b03*a31,
b00*a02+b01*a12+b02*a22+b03*a32,
b00*a03+b01*a13+b02*a23+b03*a33,
b10*a00+b11*a10+b12*a20+b13*a30,
b10*a01+b11*a11+b12*a21+b13*a31,
b10*a02+b11*a12+b12*a22+b13*a32,
b10*a03+b11*a13+b12*a23+b13*a33,
b20*a00+b21*a10+b22*a20+b23*a30,
b20*a01+b21*a11+b22*a21+b23*a31,
b20*a02+b21*a12+b22*a22+b23*a32,
b20*a03+b21*a13+b22*a23+b23*a33,
b30*a00+b31*a10+b32*a20+b33*a30,
b30*a01+b31*a11+b32*a21+b33*a31,
b30*a02+b31*a12+b32*a22+b33*a32,
b30*a03+b31*a13+b32*a23+b33*a33,
];
},
translation: function(tx,ty,tz){
return[
1,0,0,0,
0,1,0,0,
0,0,1,0,
tx,ty,tz,1,
];
},
xRotation: function(angleInRadians){
varc=Math.cos(angleInRadians);
vars=Math.sin(angleInRadians);
return[
1,0,0,0,
0,c,s,0,
0,-s,c,0,
0,0,0,1,
];
},
yRotation: function(angleInRadians){
varc=Math.cos(angleInRadians);
vars=Math.sin(angleInRadians);
return[
c,0,-s,0,
0,1,0,0,
s,0,c,0,
0,0,0,1,
];
},
zRotation: function(angleInRadians){
varc=Math.cos(angleInRadians);
vars=Math.sin(angleInRadians);
return[
c,s,0,0,
-s,c,0,0,
0,0,1,0,
0,0,0,1,
];
},
scaling: function(sx,sy,sz){
return[
sx,0,0,0,
0,sy,0,0,
0,0,sz,0,
0,0,0,1,
];
},
translate: function(m,tx,ty,tz){
returnm4.multiply(m,m4.translation(tx,ty,tz));
},
xRotate: function(m,angleInRadians){
returnm4.multiply(m,m4.xRotation(angleInRadians));
},
yRotate: function(m,angleInRadians){
returnm4.multiply(m,m4.yRotation(angleInRadians));
},
zRotate: function(m,angleInRadians){
returnm4.multiply(m,m4.zRotation(angleInRadians));
},
scale: function(m,sx,sy,sz){
returnm4.multiply(m,m4.scaling(sx,sy,sz));
},
};
// Fill the buffer with the values that define a letter 'F'.
functionsetGeometry(gl){
gl.bufferData(
gl.ARRAY_BUFFER,
newFloat32Array([
// left column front
0,0,0,
0,150,0,
30,0,0,
0,150,0,
30,150,0,
30,0,0,
// top rung front
30,0,0,
30,30,0,
100,0,0,
30,30,0,
100,30,0,
100,0,0,
// middle rung front
30,60,0,
30,90,0,
67,60,0,
30,90,0,
67,90,0,
67,60,0,
// left column back
0,0,30,
30,0,30,
0,150,30,
0,150,30,
30,0,30,
30,150,30,
// top rung back
30,0,30,
100,0,30,
30,30,30,
30,30,30,
100,0,30,
100,30,30,
// middle rung back
30,60,30,
67,60,30,
30,90,30,
30,90,30,
67,60,30,
67,90,30,
// top
0,0,0,
100,0,0,
100,0,30,
0,0,0,
100,0,30,
0,0,30,
// top rung right
100,0,0,
100,30,0,
100,30,30,
100,0,0,
100,30,30,
100,0,30,
// under top rung
30,30,0,
30,30,30,
100,30,30,
30,30,0,
100,30,30,
100,30,0,
// between top rung and middle
30,30,0,
30,60,30,
30,30,30,
30,30,0,
30,60,0,
30,60,30,
// top of middle rung
30,60,0,
67,60,30,
30,60,30,
30,60,0,
67,60,0,
67,60,30,
// right of middle rung
67,60,0,
67,90,30,
67,60,30,
67,60,0,
67,90,0,
67,90,30,
// bottom of middle rung.
30,90,0,
30,90,30,
67,90,30,
30,90,0,
67,90,30,
67,90,0,
// right of bottom
30,90,0,
30,150,30,
30,90,30,
30,90,0,
30,150,0,
30,150,30,
// bottom
0,150,0,
0,150,30,
30,150,30,
0,150,0,
30,150,30,
30,150,0,
// left side
0,0,0,
0,0,30,
0,150,30,
0,0,0,
0,150,30,
0,150,0]),
gl.STATIC_DRAW);
}
// Fill the buffer with colors for the 'F'.
functionsetColors(gl){
gl.bufferData(
gl.ARRAY_BUFFER,
newUint8Array([
// left column front
200,70,120,
200,70,120,
200,70,120,
200,70,120,
200,70,120,
200,70,120,
// top rung front
200,70,120,
200,70,120,
200,70,120,
200,70,120,
200,70,120,
200,70,120,
// middle rung front
200,70,120,
200,70,120,
200,70,120,
200,70,120,
200,70,120,
200,70,120,
// left column back
80,70,200,
80,70,200,
80,70,200,
80,70,200,
80,70,200,
80,70,200,
// top rung back
80,70,200,
80,70,200,
80,70,200,
80,70,200,
80,70,200,
80,70,200,
// middle rung back
80,70,200,
80,70,200,
80,70,200,
80,70,200,
80,70,200,
80,70,200,
// top
70,200,210,
70,200,210,
70,200,210,
70,200,210,
70,200,210,
70,200,210,
// top rung right
200,200,70,
200,200,70,
200,200,70,
200,200,70,
200,200,70,
200,200,70,
// under top rung
210,100,70,
210,100,70,
210,100,70,
210,100,70,
210,100,70,
210,100,70,
// between top rung and middle
210,160,70,
210,160,70,
210,160,70,
210,160,70,
210,160,70,
210,160,70,
// top of middle rung
70,180,210,
70,180,210,
70,180,210,
70,180,210,
70,180,210,
70,180,210,
// right of middle rung
100,70,210,
100,70,210,
100,70,210,
100,70,210,
100,70,210,
100,70,210,
// bottom of middle rung.
76,210,100,
76,210,100,
76,210,100,
76,210,100,
76,210,100,
76,210,100,
// right of bottom
140,210,80,
140,210,80,
140,210,80,
140,210,80,
140,210,80,
140,210,80,
// bottom
90,130,110,
90,130,110,
90,130,110,
90,130,110,
90,130,110,
90,130,110,
// left side
160,160,220,
160,160,220,
160,160,220,
160,160,220,
160,160,220,
160,160,220]),
gl.STATIC_DRAW);
}
main();
</script>
</html>
