Assignment 8

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Assignment 8: Teapot Assignment Due Date: Nov 15

Part I: Draw the teapot described by the Bezier control data indicated below. The data describe 32 Bezier patches which together form a teapot. You can display the teapot using wireframe methods. Basically you need to create a function bezier() that takes the control data for a Bezier cubic patch, and draws the patch. Then you read the data below, calling the function on each patch.

Crude display of a patch might use a 5x5 or 10x10 s,t curve mesh. This will generate a wireframe - with 3200 lines.

Part II: For more realism use polygon display rather than wireframe, and pipe through a hidden surface phase. In this case, display a patch as 5x5 or 10x10 polygons using the same s,t mesh - indeed each will be a quadrilateral. While the edges are slightly curved, treating them as straight will be a minimal error if you use 10x10 of them. This means that you will generate a total of 3200 polygons - you might want to test with 2x2 or 3x3 for this reason.

TEAPOT DATA:

Here is the dataset for an easily recognizable object, a common teapot. The teapot is composed of 32 Bezier patches, 28 for the body, handle, lid and spout and four more for the bottom. People often don't bother rendering the latter four if the bottom of the pot is not visible.

The control points can be seen in wireframe form in Plates II.22- 26 in the text (new edition only), in the middle of the pictures. A coarsely polygonalized version can be seen in Plate II.29. Three fancier versions can be seen in Plates II.33, 36 and 37.

The format for the data below is as follows- each patch has 16 con- trol points. The indices for those are just below in the array 'Patches'. The various parts of the teapot are labelled if you just want to dis- play part of it, the handle e.g. The numbers below are indices into a vertex array called 'Verts' that follows 'Patches' below. Verts has the object-space positions of the patch control points.

In terms of orientation, I believe the pot is upright in its defini- tion space and centered around the origin with the spout pointing down the +x axis. The whole thing is 2.4 units tall.

==================================================================

int Patches[32][4][4] = { /* rim */ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 3, 16, 17, 18, 7, 19, 20, 21, 11, 22, 23, 24, 15, 25, 26, 27, 18, 28, 29, 30, 21, 31, 32, 33, 24, 34, 35, 36, 27, 37, 38, 39, 30, 40, 41, 0, 33, 42, 43, 4, 36, 44, 45, 8, 39, 46, 47, 12, /* body */ 12, 13, 14, 15, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 15, 25, 26, 27, 51, 60, 61, 62, 55, 63, 64, 65, 59, 66, 67, 68, 27, 37, 38, 39, 62, 69, 70, 71, 65, 72, 73, 74, 68, 75, 76, 77, 39, 46, 47, 12, 71, 78, 79, 48, 74, 80, 81, 52, 77, 82, 83, 56, 56, 57, 58, 59, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 59, 66, 67, 68, 87, 96, 97, 98, 91, 99, 100, 101, 95, 102, 103, 104, 68, 75, 76, 77, 98, 105, 106, 107, 101, 108, 109, 110, 104, 111, 112, 113, 77, 82, 83, 56, 107, 114, 115, 84, 110, 116, 117, 88, 113, 118, 119, 92, /* handle */ 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 123, 136, 137, 120, 127, 138, 139, 124, 131, 140, 141, 128, 135, 142, 143, 132, 132, 133, 134, 135, 144, 145, 146, 147, 148, 149, 150, 151, 68, 152, 153, 154, 135, 142, 143, 132, 147, 155, 156, 144, 151, 157, 158, 148, 154, 159, 160, 68, /* spout */ 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 164, 177, 178, 161, 168, 179, 180, 165, 172, 181, 182, 169, 176, 183, 184, 173, 173, 174, 175, 176, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 176, 183, 184, 173, 188, 197, 198, 185, 192, 199, 200, 189, 196, 201, 202, 193, /* lid */ 203, 203, 203, 203, 204, 205, 206, 207, 208, 208, 208, 208, 209, 210, 211, 212, 203, 203, 203, 203, 207, 213, 214, 215, 208, 208, 208, 208, 212, 216, 217, 218, 203, 203, 203, 203, 215, 219, 220, 221, 208, 208, 208, 208, 218, 222, 223, 224, 203, 203, 203, 203, 221, 225, 226, 204, 208, 208, 208, 208, 224, 227, 228, 209, 209, 210, 211, 212, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 212, 216, 217, 218, 232, 241, 242, 243, 236, 244, 245, 246, 240, 247, 248, 249, 218, 222, 223, 224, 243, 250, 251, 252, 246, 253, 254, 255, 249, 256, 257, 258, 224, 227, 228, 209, 252, 259, 260, 229, 255, 261, 262, 233, 258, 263, 264, 237, /* bottom */ 265, 265, 265, 265, 266, 267, 268, 269, 270, 271, 272, 273, 92, 119, 118, 113, 265, 265, 265, 265, 269, 274, 275, 276, 273, 277, 278, 279, 113, 112, 111, 104, 265, 265, 265, 265, 276, 280, 281, 282, 279, 283, 284, 285, 104, 103, 102, 95, 265, 265, 265, 265, 282, 286, 287, 266, 285, 288, 289, 270, 95, 94, 93, 92 } ;

COORD3 Verts[290] = { 1.4, 0, 2.4, 1.4, -0.784, 2.4, 0.784, -1.4, 2.4, 0, -1.4, 2.4, 1.3375, 0, 2.53125, 1.3375, -0.749, 2.53125, 0.749, -1.3375, 2.53125, 0, -1.3375, 2.53125, 1.4375, 0, 2.53125, 1.4375, -0.805, 2.53125, 0.805, -1.4375, 2.53125, 0, -1.4375, 2.53125, 1.5, 0, 2.4, 1.5, -0.84, 2.4, 0.84, -1.5, 2.4, 0, -1.5, 2.4, -0.784, -1.4, 2.4, -1.4, -0.784, 2.4, -1.4, 0, 2.4, -0.749, -1.3375, 2.53125, -1.3375, -0.749, 2.53125, -1.3375, 0, 2.53125, -0.805, -1.4375, 2.53125, -1.4375, -0.805, 2.53125, -1.4375, 0, 2.53125, -0.84, -1.5, 2.4, -1.5, -0.84, 2.4, -1.5, 0, 2.4, -1.4, 0.784, 2.4, -0.784, 1.4, 2.4, 0, 1.4, 2.4, -1.3375, 0.749, 2.53125, -0.749, 1.3375, 2.53125, 0, 1.3375, 2.53125, -1.4375, 0.805, 2.53125, -0.805, 1.4375, 2.53125, 0, 1.4375, 2.53125, -1.5, 0.84, 2.4, -0.84, 1.5, 2.4, 0, 1.5, 2.4, 0.784, 1.4, 2.4, 1.4, 0.784, 2.4, 0.749, 1.3375, 2.53125, 1.3375, 0.749, 2.53125, 0.805, 1.4375, 2.53125, 1.4375, 0.805, 2.53125, 0.84, 1.5, 2.4, 1.5, 0.84, 2.4, 1.75, 0, 1.875, 1.75, -0.98, 1.875, 0.98, -1.75, 1.875, 0, -1.75, 1.875, 2, 0, 1.35, 2, -1.12, 1.35, 1.12, -2, 1.35, 0, -2, 1.35, 2, 0, 0.9, 2, -1.12, 0.9, 1.12, -2, 0.9, 0, -2, 0.9, -0.98, -1.75, 1.875, -1.75, -0.98, 1.875, -1.75, 0, 1.875, -1.12, -2, 1.35, -2, -1.12, 1.35, -2, 0, 1.35, -1.12, -2, 0.9, -2, -1.12, 0.9, -2, 0, 0.9, -1.75, 0.98, 1.875, -0.98, 1.75, 1.875, 0, 1.75, 1.875, -2, 1.12, 1.35, -1.12, 2, 1.35, 0, 2, 1.35, -2, 1.12, 0.9, -1.12, 2, 0.9, 0, 2, 0.9, 0.98, 1.75, 1.875, 1.75, 0.98, 1.875, 1.12, 2, 1.35, 2, 1.12, 1.35, 1.12, 2, 0.9, 2, 1.12, 0.9, 2, 0, 0.45, 2, -1.12, 0.45, 1.12, -2, 0.45, 0, -2, 0.45, 1.5, 0, 0.225, 1.5, -0.84, 0.225, 0.84, -1.5, 0.225, 0, -1.5, 0.225, 1.5, 0, 0.15, 1.5, -0.84, 0.15, 0.84, -1.5, 0.15, 0, -1.5, 0.15, -1.12, -2, 0.45, -2, -1.12, 0.45, -2, 0, 0.45, -0.84, -1.5, 0.225, -1.5, -0.84, 0.225, -1.5, 0, 0.225, -0.84, -1.5, 0.15, -1.5, -0.84, 0.15, -1.5, 0, 0.15, -2, 1.12, 0.45, -1.12, 2, 0.45, 0, 2, 0.45, -1.5, 0.84, 0.225, -0.84, 1.5, 0.225, 0, 1.5, 0.225, -1.5, 0.84, 0.15, -0.84, 1.5, 0.15, 0, 1.5, 0.15, 1.12, 2, 0.45, 2, 1.12, 0.45, 0.84, 1.5, 0.225, 1.5, 0.84, 0.225, 0.84, 1.5, 0.15, 1.5, 0.84, 0.15, -1.6, 0, 2.025, -1.6, -0.3, 2.025, -1.5, -0.3, 2.25, -1.5, 0, 2.25, -2.3, 0, 2.025, -2.3, -0.3, 2.025, -2.5, -0.3, 2.25, -2.5, 0, 2.25, -2.7, 0, 2.025, -2.7, -0.3, 2.025, -3, -0.3, 2.25, -3, 0, 2.25, -2.7, 0, 1.8, -2.7, -0.3, 1.8, -3, -0.3, 1.8, -3, 0, 1.8, -1.5, 0.3, 2.25, -1.6, 0.3, 2.025, -2.5, 0.3, 2.25, -2.3, 0.3, 2.025, -3, 0.3, 2.25, -2.7, 0.3, 2.025, -3, 0.3, 1.8, -2.7, 0.3, 1.8, -2.7, 0, 1.575, -2.7, -0.3, 1.575, -3, -0.3, 1.35, -3, 0, 1.35, -2.5, 0, 1.125, -2.5, -0.3, 1.125, -2.65, -0.3, 0.9375, -2.65, 0, 0.9375, -2, -0.3, 0.9, -1.9, -0.3, 0.6, -1.9, 0, 0.6, -3, 0.3, 1.35, -2.7, 0.3, 1.575, -2.65, 0.3, 0.9375, -2.5, 0.3, 1.125, -1.9, 0.3, 0.6, -2, 0.3, 0.9, 1.7, 0, 1.425, 1.7, -0.66, 1.425, 1.7, -0.66, 0.6, 1.7, 0, 0.6, 2.6, 0, 1.425, 2.6, -0.66, 1.425, 3.1, -0.66, 0.825, 3.1, 0, 0.825, 2.3, 0, 2.1, 2.3, -0.25, 2.1, 2.4, -0.25, 2.025, 2.4, 0, 2.025, 2.7, 0, 2.4, 2.7, -0.25, 2.4, 3.3, -0.25, 2.4, 3.3, 0, 2.4, 1.7, 0.66, 0.6, 1.7, 0.66, 1.425, 3.1, 0.66, 0.825, 2.6, 0.66, 1.425, 2.4, 0.25, 2.025, 2.3, 0.25, 2.1, 3.3, 0.25, 2.4, 2.7, 0.25, 2.4, 2.8, 0, 2.475, 2.8, -0.25, 2.475, 3.525, -0.25, 2.49375, 3.525, 0, 2.49375, 2.9, 0, 2.475, 2.9, -0.15, 2.475, 3.45, -0.15, 2.5125, 3.45, 0, 2.5125, 2.8, 0, 2.4, 2.8, -0.15, 2.4, 3.2, -0.15, 2.4, 3.2, 0, 2.4, 3.525, 0.25, 2.49375, 2.8, 0.25, 2.475, 3.45, 0.15, 2.5125, 2.9, 0.15, 2.475, 3.2, 0.15, 2.4, 2.8, 0.15, 2.4, 0, 0, 3.15, 0.8, 0, 3.15, 0.8, -0.45, 3.15, 0.45, -0.8, 3.15, 0, -0.8, 3.15, 0, 0, 2.85, 0.2, 0, 2.7, 0.2, -0.112, 2.7, 0.112, -0.2, 2.7, 0, -0.2, 2.7, -0.45, -0.8, 3.15, -0.8, -0.45, 3.15, -0.8, 0, 3.15, -0.112, -0.2, 2.7, -0.2, -0.112, 2.7, -0.2, 0, 2.7, -0.8, 0.45, 3.15, -0.45, 0.8, 3.15, 0, 0.8, 3.15, -0.2, 0.112, 2.7, -0.112, 0.2, 2.7, 0, 0.2, 2.7, 0.45, 0.8, 3.15, 0.8, 0.45, 3.15, 0.112, 0.2, 2.7, 0.2, 0.112, 2.7, 0.4, 0, 2.55, 0.4, -0.224, 2.55, 0.224, -0.4, 2.55, 0, -0.4, 2.55, 1.3, 0, 2.55, 1.3, -0.728, 2.55, 0.728, -1.3, 2.55, 0, -1.3, 2.55, 1.3, 0, 2.4, 1.3, -0.728, 2.4, 0.728, -1.3, 2.4, 0, -1.3, 2.4, -0.224, -0.4, 2.55, -0.4, -0.224, 2.55, -0.4, 0, 2.55, -0.728, -1.3, 2.55, -1.3, -0.728, 2.55, -1.3, 0, 2.55, -0.728, -1.3, 2.4, -1.3, -0.728, 2.4, -1.3, 0, 2.4, -0.4, 0.224, 2.55, -0.224, 0.4, 2.55, 0, 0.4, 2.55, -1.3, 0.728, 2.55, -0.728, 1.3, 2.55, 0, 1.3, 2.55, -1.3, 0.728, 2.4, -0.728, 1.3, 2.4, 0, 1.3, 2.4, 0.224, 0.4, 2.55, 0.4, 0.224, 2.55, 0.728, 1.3, 2.55, 1.3, 0.728, 2.55, 0.728, 1.3, 2.4, 1.3, 0.728, 2.4, 0, 0, 0, 1.425, 0, 0, 1.425, 0.798, 0, 0.798, 1.425, 0, 0, 1.425, 0, 1.5, 0, 0.075, 1.5, 0.84, 0.075, 0.84, 1.5, 0.075, 0, 1.5, 0.075, -0.798, 1.425, 0, -1.425, 0.798, 0, -1.425, 0, 0, -0.84, 1.5, 0.075, -1.5, 0.84, 0.075, -1.5, 0, 0.075, -1.425, -0.798, 0, -0.798, -1.425, 0, 0, -1.425, 0, -1.5, -0.84, 0.075, -0.84, -1.5, 0.075, 0, -1.5, 0.075, 0.798, -1.425, 0, 1.425, -0.798, 0, 0.84, -1.5, 0.075, 1.5, -0.84, 0.075 } ;


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