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cup_edit/thermion_dart/lib/src/utils/geometry.dart
2024-09-26 16:35:33 +08:00

334 lines
8.5 KiB
Dart

import 'dart:math';
import 'dart:typed_data';
import '../../thermion_dart.dart';
class GeometryHelper {
static Geometry sphere({bool normals = true, bool uvs = true}) {
int latitudeBands = 20;
int longitudeBands = 20;
List<double> verticesList = [];
List<double> normalsList = [];
List<double> uvsList = [];
List<int> indices = [];
for (int latNumber = 0; latNumber <= latitudeBands; latNumber++) {
double theta = latNumber * pi / latitudeBands;
double sinTheta = sin(theta);
double cosTheta = cos(theta);
for (int longNumber = 0; longNumber <= longitudeBands; longNumber++) {
double phi = longNumber * 2 * pi / longitudeBands;
double sinPhi = sin(phi);
double cosPhi = cos(phi);
double x = cosPhi * sinTheta;
double y = cosTheta;
double z = sinPhi * sinTheta;
verticesList.addAll([x, y, z]);
normalsList.addAll([x, y, z]);
uvsList.addAll([longNumber / longitudeBands, latNumber / latitudeBands]);
}
}
for (int latNumber = 0; latNumber < latitudeBands; latNumber++) {
for (int longNumber = 0; longNumber < longitudeBands; longNumber++) {
int first = (latNumber * (longitudeBands + 1)) + longNumber;
int second = first + longitudeBands + 1;
indices.addAll([first, second, first + 1, second, second + 1, first + 1]);
}
}
Float32List vertices = Float32List.fromList(verticesList);
Float32List? _normals = normals ? Float32List.fromList(normalsList) : null;
Float32List? _uvs = uvs ? Float32List.fromList(uvsList) : null;
return Geometry(vertices, indices, normals: _normals, uvs: _uvs);
}
static Geometry cube({bool normals = true, bool uvs = true}) {
final vertices = Float32List.fromList([
// Front face
-1, -1, 1,
1, -1, 1,
1, 1, 1,
-1, 1, 1,
// Back face
-1, -1, -1,
-1, 1, -1,
1, 1, -1,
1, -1, -1,
// Top face
-1, 1, -1,
-1, 1, 1,
1, 1, 1,
1, 1, -1,
// Bottom face
-1, -1, -1,
1, -1, -1,
1, -1, 1,
-1, -1, 1,
// Right face
1, -1, -1,
1, 1, -1,
1, 1, 1,
1, -1, 1,
// Left face
-1, -1, -1,
-1, -1, 1,
-1, 1, 1,
-1, 1, -1,
]);
final _normals = normals ? Float32List.fromList([
// Front face
0, 0, 1,
0, 0, 1,
0, 0, 1,
0, 0, 1,
// Back face
0, 0, -1,
0, 0, -1,
0, 0, -1,
0, 0, -1,
// Top face
0, 1, 0,
0, 1, 0,
0, 1, 0,
0, 1, 0,
// Bottom face
0, -1, 0,
0, -1, 0,
0, -1, 0,
0, -1, 0,
// Right face
1, 0, 0,
1, 0, 0,
1, 0, 0,
1, 0, 0,
// Left face
-1, 0, 0,
-1, 0, 0,
-1, 0, 0,
-1, 0, 0,
]) : null;
final _uvs = uvs ? Float32List.fromList([
// Front face
1/3, 1/3,
2/3, 1/3,
2/3, 2/3,
1/3, 2/3,
// Back face
2/3, 2/3,
2/3, 1,
1, 1,
1, 2/3,
// Top face
1/3, 0,
1/3, 1/3,
2/3, 1/3,
2/3, 0,
// Bottom face
1/3, 2/3,
2/3, 2/3,
2/3, 1,
1/3, 1,
// Right face
2/3, 1/3,
2/3, 2/3,
1, 2/3,
1, 1/3,
// Left face
0, 1/3,
1/3, 1/3,
1/3, 2/3,
0, 2/3,
]) : null;
final indices = [
// Front face
0, 1, 2, 0, 2, 3,
// Back face
4, 5, 6, 4, 6, 7,
// Top face
8, 9, 10, 8, 10, 11,
// Bottom face
12, 13, 14, 12, 14, 15,
// Right face
16, 17, 18, 16, 18, 19,
// Left face
20, 21, 22, 20, 22, 23
];
return Geometry(vertices, indices, normals: _normals, uvs: _uvs);
}
static Geometry cylinder({double radius = 1.0, double length = 1.0, bool normals = true, bool uvs = true }) {
int segments = 32;
List<double> verticesList = [];
List<double> normalsList = [];
List<double> uvsList = [];
List<int> indices = [];
// Create vertices, normals, and UVs
for (int i = 0; i <= segments; i++) {
double theta = i * 2 * pi / segments;
double x = radius * cos(theta);
double z = radius * sin(theta);
// Top circle
verticesList.addAll([x, length / 2, z]);
normalsList.addAll([x / radius, 0, z / radius]);
uvsList.addAll([i / segments, 1]);
// Bottom circle
verticesList.addAll([x, -length / 2, z]);
normalsList.addAll([x / radius, 0, z / radius]);
uvsList.addAll([i / segments, 0]);
}
// Create indices
for (int i = 0; i < segments; i++) {
int topFirst = i * 2;
int topSecond = (i + 1) * 2;
int bottomFirst = topFirst + 1;
int bottomSecond = topSecond + 1;
// Top face (counter-clockwise)
indices.addAll([segments * 2, topSecond, topFirst]);
// Bottom face (counter-clockwise when viewed from below)
indices.addAll([segments * 2 + 1, bottomFirst, bottomSecond]);
// Side faces (counter-clockwise)
indices.addAll([topFirst, bottomFirst, topSecond]);
indices.addAll([bottomFirst, bottomSecond, topSecond]);
}
// Add center vertices, normals, and UVs for top and bottom faces
verticesList.addAll([0, length / 2, 0]); // Top center
normalsList.addAll([0, 1, 0]);
uvsList.addAll([0.5, 0.5]); // Center of top face
verticesList.addAll([0, -length / 2, 0]); // Bottom center
normalsList.addAll([0, -1, 0]);
uvsList.addAll([0.5, 0.5]); // Center of bottom face
// Add top and bottom face normals and UVs
for (int i = 0; i <= segments; i++) {
normalsList.addAll([0, 1, 0]); // Top face normal
normalsList.addAll([0, -1, 0]); // Bottom face normal
double u = 0.5 + 0.5 * cos(i * 2 * pi / segments);
double v = 0.5 + 0.5 * sin(i * 2 * pi / segments);
uvsList.addAll([u, v]); // Top face UV
uvsList.addAll([u, v]); // Bottom face UV
}
Float32List vertices = Float32List.fromList(verticesList);
Float32List? _normals = normals ? Float32List.fromList(normalsList) : null;
Float32List? _uvs = uvs ? Float32List.fromList(uvsList) : null;
return Geometry(vertices, indices, normals: _normals, uvs: _uvs);
}
static Geometry conic({double radius = 1.0, double length = 1.0, bool normals = true, bool uvs = true}) {
int segments = 32;
List<double> verticesList = [];
List<double> normalsList = [];
List<double> uvsList = [];
List<int> indices = [];
// Create vertices, normals, and UVs
for (int i = 0; i <= segments; i++) {
double theta = i * 2 * pi / segments;
double x = radius * cos(theta);
double z = radius * sin(theta);
// Base circle
verticesList.addAll([x, 0, z]);
// Calculate normal for the side
double nx = x / sqrt(x * x + length * length);
double nz = z / sqrt(z * z + length * length);
double ny = radius / sqrt(radius * radius + length * length);
normalsList.addAll([nx, ny, nz]);
// UV coordinates
uvsList.addAll([i / segments, 0]);
}
// Apex
verticesList.addAll([0, length, 0]);
normalsList.addAll([0, 1, 0]); // Normal at apex points straight up
uvsList.addAll([0.5, 1]); // UV for apex
// Create indices
for (int i = 0; i < segments; i++) {
// Base face (fixed to counterclockwise)
indices.addAll([segments + 1, i + 1, i]);
// Side faces (already correct)
indices.addAll([i, segments, i + 1]);
}
// Add base face normals and UVs
for (int i = 0; i <= segments; i++) {
normalsList.addAll([0, -1, 0]); // Base face normal
double u = 0.5 + 0.5 * cos(i * 2 * pi / segments);
double v = 0.5 + 0.5 * sin(i * 2 * pi / segments);
uvsList.addAll([u, v]); // Base face UV
}
Float32List vertices = Float32List.fromList(verticesList);
Float32List? _normals = normals ? Float32List.fromList(normalsList) : null;
Float32List? _uvs = uvs ? Float32List.fromList(uvsList) : null;
return Geometry(vertices, indices, normals: _normals, uvs: _uvs);
}
static Geometry plane({double width = 1.0, double height = 1.0, bool normals = true, bool uvs = true}) {
Float32List vertices = Float32List.fromList([
-width / 2, 0, -height / 2,
width / 2, 0, -height / 2,
width / 2, 0, height / 2,
-width / 2, 0, height / 2,
]);
Float32List? _normals = normals ? Float32List.fromList([
0, 1, 0,
0, 1, 0,
0, 1, 0,
0, 1, 0,
]) : null;
Float32List? _uvs = uvs ? Float32List.fromList([
0, 0,
1, 0,
1, 1,
0, 1,
]) : null;
List<int> indices = [
0, 2, 1,
0, 3, 2,
];
return Geometry(vertices, indices, normals: _normals, uvs: _uvs);
}
}