STUDIO/anim4.html at main · DO-SAY-GO/STUDIO · GitHub

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
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>3-Point Perspective Cube with Matrix</title>
  <style>
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      overflow: hidden;
      background: dodgerblue;
    }

    canvas {
      display: block;
      width: 100vw;
      height: 100vh;
    }

    .debug-checkbox {
      position: absolute;
      top: 1em;
      left: 1em;
      background: rgba(255, 255, 255, 0.8);
      padding: 0.5em;
      border-radius: 4px;
      font-family: Arial, sans-serif;
    }
  </style>
</head>
<body>
  <canvas id="cubeCanvas"></canvas>
  <div class="debug-checkbox">
    <label>
      <input type="checkbox" id="debugLines"> Show Debug Lines
    </label>
  </div>

  <script>
    // Imports, constants then state
    const canvas = document.getElementById('cubeCanvas');
    if (!canvas) {
      console.error('Canvas element not found!');
    }

    const ctx = canvas.getContext('2d');
    if (!ctx) {
      console.error('Failed to get 2D context for Canvas!');
    }

    const debugCheckbox = document.getElementById('debugLines');
    let showDebugLines = false;

    let horizonY = canvas.height * 0.3; // Adjusted horizon to 30% from top
    let vp1 = { x: 0, y: 0 }; // Will be computed dynamically
    let vp2 = { x: 0, y: 0 };
    let vp3 = { x: 0, y: 0 };

    const fov = Math.PI / 4; // Reduced to 45 degrees
    const near = 0.1;
    const far = 1000;

    // Camera parameters
    const eye = { x: 50, y: 50, z: 50 }; // Moved closer
    const center = { x: 0, y: 0, z: 0 };
    const up = { x: 0, y: 1, z: 0 };

    const cubeSize = 50; // Reduced from 100 to 50
    const cube = {
      center: { x: 0, y: 0, z: 0 },
      vertices: [],
      faces: [
        { vertices: [0, 1, 5, 4], color: '#808080' }, // Front
        { vertices: [2, 3, 7, 6], color: '#808080' }, // Back
        { vertices: [0, 3, 7, 4], color: '#808080' }, // Left
        { vertices: [1, 2, 6, 5], color: '#808080' }, // Right
        { vertices: [4, 5, 6, 7], color: '#808080' }, // Top
        { vertices: [0, 1, 2, 3], color: '#808080' }  // Bottom
      ],
      edges: [
        { v1: 0, v2: 1, dir: 'x', vp: 'vp2' }, // Bottom front
        { v1: 1, v2: 2, dir: 'z', vp: 'vp2' }, // Bottom right
        { v1: 2, v2: 3, dir: 'x', vp: 'vp1' }, // Bottom back
        { v1: 3, v2: 0, dir: 'z', vp: 'vp1' }, // Bottom left
        { v1: 4, v2: 5, dir: 'x', vp: 'vp2' }, // Top front
        { v1: 5, v2: 6, dir: 'z', vp: 'vp2' }, // Top right
        { v1: 6, v2: 7, dir: 'x', vp: 'vp1' }, // Top back
        { v1: 7, v2: 4, dir: 'z', vp: 'vp1' }, // Top left
        { v1: 0, v2: 4, dir: 'y', vp: 'vp3' }, // Front left vertical
        { v1: 1, v2: 5, dir: 'y', vp: 'vp3' }, // Front right vertical
        { v1: 2, v2: 6, dir: 'y', vp: 'vp3' }, // Back right vertical
        { v1: 3, v2: 7, dir: 'y', vp: 'vp3' }  // Back left vertical
      ]
    };

    const floor = {
      points: [
        { x: -canvas.width, y: 0, z: -400 },
        { x: canvas.width, y: 0, z: -400 },
        { x: canvas.width, y: 0, z: 400 },
        { x: -canvas.width, y: 0, z: 400 }
      ]
    };

    // Logic
    window.addEventListener('resize', resizeCanvas);
    debugCheckbox.addEventListener('change', () => {
      showDebugLines = debugCheckbox.checked;
      render();
    });
    resizeCanvas();
    initializeCube();
    render();

    // Functions
    function resizeCanvas() {
      canvas.width = window.innerWidth;
      canvas.height = window.innerHeight;
      horizonY = canvas.height * 0.3;
      initializeCube();
      render();
    }

    function initializeCube() {
      const { x: cx, y: cy, z: cz } = cube.center;
      const s = cubeSize / 2;
      cube.vertices = [
        { x: cx - s, y: cy, z: cz + s },       // 0: Bottom front left
        { x: cx + s, y: cy, z: cz + s },       // 1: Bottom front right
        { x: cx + s, y: cy, z: cz - s },       // 2: Bottom back right
        { x: cx - s, y: cy, z: cz - s },       // 3: Bottom back left
        { x: cx - s, y: cy + cubeSize, z: cz + s }, // 4: Top front left
        { x: cx + s, y: cy + cubeSize, z: cz + s }, // 5: Top front right
        { x: cx + s, y: cy + cubeSize, z: cz - s }, // 6: Top back right
        { x: cx - s, y: cy + cubeSize, z: cz - s }  // 7: Top back left
      ];
      console.log('Cube vertices:', cube.vertices);
    }

    function subtract(v1, v2) {
      return {
        x: v1.x - v2.x,
        y: v1.y - v2.y,
        z: v1.z - v2.z
      };
    }

    function normalize(v) {
      const len = Math.sqrt(v.x * v.x + v.y * v.y + v.z * v.z);
      if (len === 0) return v;
      return {
        x: v.x / len,
        y: v.y / len,
        z: v.z / len
      };
    }

    function cross(v1, v2) {
      return {
        x: v1.y * v2.z - v1.z * v2.y,
        y: v1.z * v2.x - v1.x * v2.z,
        z: v1.x * v2.y - v1.y * v2.x
      };
    }

    function dot(v1, v2) {
      return v1.x * v2.x + v1.y * v2.y + v1.z * v2.z;
    }

    function lookAt(eye, center, up) {
      const f = normalize(subtract(center, eye));
      const s = normalize(cross(up, f));
      const u = cross(f, s);
      return [
        [s.x, s.y, s.z, -dot(s, eye)],
        [u.x, u.y, u.z, -dot(u, eye)],
        [-f.x, -f.y, -f.z, -dot({ x: -f.x, y: -f.y, z: -f.z }, eye)],
        [0, 0, 0, 1]
      ];
    }

    function perspective(fov, aspect, near, far) {
      const f = 1 / Math.tan(fov / 2);
      const rangeInv = 1 / (near - far);
      return [
        [f / aspect, 0, 0, 0],
        [0, f, 0, 0],
        [0, 0, (near + far) * rangeInv, near * far * rangeInv * 2],
        [0, 0, -1, 0]
      ];
    }

    function multiplyMatrixVector(matrix, vector) {
      const result = [0, 0, 0, 0];
      for (let i = 0; i < 4; i++) {
        for (let j = 0; j < 4; j++) {
          result[i] += matrix[i][j] * vector[j];
        }
      }
      return result;
    }

    function projectVertex(vertex, viewMatrix, projMatrix, width, height) {
      const v = [vertex.x, vertex.y, vertex.z, 1];
      const vCamera = multiplyMatrixVector(viewMatrix, v);
      const vProj = multiplyMatrixVector(projMatrix, vCamera);
      if (vProj[3] === 0) {
        console.error('Invalid projection, w = 0:', vertex);
        return null;
      }
      const x = vProj[0] / vProj[3];
      const y = vProj[1] / vProj[3];
      const screenX = (x + 1) * (width / 2);
      const screenY = (1 - y) * (height / 2);
      return { x: screenX, y: screenY };
    }

    function project(x, y, z) {
      const viewMatrix = lookAt(eye, center, up);
      const aspect = canvas.width / canvas.height;
      const projMatrix = perspective(fov, aspect, near, far);
      return projectVertex({ x, y, z }, viewMatrix, projMatrix, canvas.width, canvas.height);
    }

    function drawFace(object, face) {
      try {
        const viewMatrix = lookAt(eye, center, up);
        const aspect = canvas.width / canvas.height;
        const projMatrix = perspective(fov, aspect, near, far);

        const points2D = face.vertices.map(index => projectVertex(
          object.vertices[index],
          viewMatrix,
          projMatrix,
          canvas.width,
          canvas.height
        ));

        if (points2D.some(p => p === null)) {
          console.error('Projection failed for some vertices');
          return;
        }

        const p0 = points2D[0], p1 = points2D[1], p2 = points2D[2];
        const cross = (p1.x - p0.x) * (p2.y - p0.y) - (p1.y - p0.y) * (p2.x - p0.x);
        if (cross <= 0) {
          console.log('Skipping backface, cross:', cross);
          return;
        }

        ctx.save();
        ctx.beginPath();
        ctx.moveTo(points2D[0].x, points2D[0].y);
        for (let i = 1; i < points2D.length; i++) {
          ctx.lineTo(points2D[i].x, points2D[i].y);
        }
        ctx.closePath();
        ctx.fillStyle = face.color;
        ctx.fill();
        ctx.strokeStyle = 'black';
        ctx.lineWidth = 2;
        ctx.stroke();
        ctx.restore();

        console.log('Face projected points:', points2D.map(p => ({ x: p.x, y: p.y })));
      } catch (error) {
        console.error('Error drawing face:', error);
      }
    }

    function drawFloor() {
      try {
        ctx.save();
        const points2D = floor.points.map(point => project(point.x, point.y, point.z));
        if (points2D.some(p => p === null)) {
          console.error('Projection failed for some floor vertices');
          return;
        }
        ctx.beginPath();
        ctx.moveTo(points2D[0].x, points2D[0].y);
        for (let i = 1; i < points2D.length; i++) {
          ctx.lineTo(points2D[i].x, points2D[i].y);
        }
        ctx.closePath();
        ctx.fillStyle = '#2A2A2A';
        ctx.fill();
        ctx.restore();

        console.log('Floor projected points:', points2D.map(p => ({ x: p.x, y: p.y })));
      } catch (error) {
        console.error('Error drawing floor:', error);
      }
    }

    function drawGuides() {
      ctx.save();
      ctx.beginPath();
      ctx.moveTo(0, horizonY);
      ctx.lineTo(canvas.width, horizonY);
      ctx.strokeStyle = 'red';
      ctx.lineWidth = 2;
      ctx.stroke();

      // Draw vanishing points as yellow balls
      ctx.fillStyle = 'yellow';
      ctx.beginPath();
      ctx.arc(vp1.x, vp1.y, 5, 0, Math.PI * 2);
      ctx.fill();
      ctx.beginPath();
      ctx.arc(vp2.x, vp2.y, 5, 0, Math.PI * 2);
      ctx.fill();
      ctx.beginPath();
      ctx.arc(vp3.x, vp3.y, 5, 0, Math.PI * 2);
      ctx.fill();
      ctx.restore();
    }

    function drawDebugLines() {
      ctx.save();
      ctx.strokeStyle = 'yellow';
      ctx.lineWidth = 1;
      ctx.setLineDash([5, 5]);

      // Compute vanishing points dynamically
      const vpX = project(10000, 0, 0);
      const vpY = project(0, 10000, 0);
      const vpZ = project(0, 0, 10000);
      console.log('Vanishing points:', { vpX, vpY, vpZ });

      // Update vanishing point positions for drawing
      if (vpX) vp1 = { x: vpX.x, y: vpX.y };
      if (vpZ) vp2 = { x: vpZ.x, y: vpZ.y };
      if (vpY) vp3 = { x: vpY.x, y: vpY.y };

      cube.edges.forEach(edge => {
        const v1 = cube.vertices[edge.v1];
        const v2 = cube.vertices[edge.v2];
        const p1 = project(v1.x, v1.y, v1.z);
        const p2 = project(v2.x, v2.y, v2.z);
        if (!p1 || !p2) return;

        let vp;
        if (edge.vp === 'vp1') vp = vp1;
        else if (edge.vp === 'vp2') vp = vp2;
        else vp = vp3;

        const dist1 = Math.hypot(p1.x - vp.x, p1.y - vp.y);
        const dist2 = Math.hypot(p2.x - vp.x, p2.y - vp.y);
        const startPoint = dist1 > dist2 ? p1 : p2;

        ctx.beginPath();
        ctx.moveTo(startPoint.x, startPoint.y);
        ctx.lineTo(vp.x, vp.y);
        ctx.stroke();
        console.log(`Debug line for edge (${edge.v1}, ${edge.v2}) dir=${edge.dir} to ${edge.vp} from (${startPoint.x}, ${startPoint.y}) to (${vp.x}, ${vp.y})`);
      });

      ctx.setLineDash([]);
      ctx.restore();
    }

    function render() {
      try {
        ctx.clearRect(0, 0, canvas.width, canvas.height);

        drawFloor();
        drawGuides();

        const sortedFaces = cube.faces.map(face => {
          const avgZ = face.vertices.reduce((sum, idx) => sum + cube.vertices[idx].z, 0) / face.vertices.length;
          return { face, avgZ };
        }).sort((a, b) => b.avgZ - a.avgZ);

        console.log('Sorted faces by avgZ:', sortedFaces.map(f => f.avgZ));

        sortedFaces.forEach(({ face }) => {
          drawFace(cube, face);
        });

        if (showDebugLines) {
          drawDebugLines();
        }
      } catch (error) {
        console.error('Error in render:', error);
      }
    }
  </script>
</body>
</html>