mirror of
https://github.com/xiaoqidun/ofdgo.git
synced 2026-10-29 16:59:27 +08:00
345 lines
9.8 KiB
Go
345 lines
9.8 KiB
Go
// Copyright 2025-2026 肖其顿 (XIAO QI DUN)
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package ofdgo
|
|
|
|
import (
|
|
"fmt"
|
|
"io"
|
|
)
|
|
|
|
// U3DMesh 保存静态三角面、线段和点的共享属性数组，索引对应原始作者几何
|
|
type U3DMesh struct {
|
|
Name string
|
|
ExcludeNormals bool
|
|
Positions, Normals [][3]float32
|
|
Diffuse, Specular, TextureCoordinates [][4]float32
|
|
Shadings []U3DShading
|
|
Faces []U3DFace
|
|
Lines []U3DLine
|
|
Points []U3DPoint
|
|
Bones []U3DBone
|
|
BoneWeights []U3DBoneWeights
|
|
Animations []U3DAnimation
|
|
Quality [3]uint32
|
|
InverseQuantization [5]float32
|
|
NormalCrease, NormalUpdate, NormalTolerance float32
|
|
}
|
|
|
|
// U3DShading 描述图元使用的颜色及纹理坐标，纹理维数依层排列
|
|
type U3DShading struct {
|
|
Attributes uint32
|
|
TextureDimensions []uint32
|
|
OriginalID uint32
|
|
}
|
|
|
|
// U3DFace 保存着色描述索引和依原始绕序排列的三个角点
|
|
type U3DFace struct {
|
|
Shading uint32
|
|
Corners [3]U3DCorner
|
|
}
|
|
|
|
// U3DLine 保存着色描述及线段两端的独立属性索引
|
|
type U3DLine struct {
|
|
Shading uint32
|
|
Corners [2]U3DCorner
|
|
}
|
|
|
|
// U3DPoint 保存点集着色描述及独立属性索引
|
|
type U3DPoint struct {
|
|
Shading uint32
|
|
Corners [1]U3DCorner
|
|
}
|
|
|
|
// U3DCorner 保存各属性索引，未启用的属性不可用于访问数组
|
|
type U3DCorner struct {
|
|
Position, Normal, Diffuse, Specular uint32
|
|
Texture [8]uint32
|
|
}
|
|
|
|
// u3dMeshDeclaration 保存几何声明及续块接收状态
|
|
type u3dMeshDeclaration struct {
|
|
mesh U3DMesh
|
|
counts [7]uint32
|
|
decoded bool
|
|
line *u3dLineState
|
|
points bool
|
|
}
|
|
|
|
// primitive 访问三角面、线段或点的着色编号和角点，不复制属性数组
|
|
// 入参: index 图元下标，依次为三角面、线段和点
|
|
// 返回: uint32 着色编号, []U3DCorner 原数组中的角点切片
|
|
func (m *U3DMesh) primitive(index int) (uint32, []U3DCorner) {
|
|
if index < len(m.Faces) {
|
|
return m.Faces[index].Shading, m.Faces[index].Corners[:]
|
|
}
|
|
index -= len(m.Faces)
|
|
if index < len(m.Lines) {
|
|
line := &m.Lines[index]
|
|
return line.Shading, line.Corners[:]
|
|
}
|
|
point := &m.Points[index-len(m.Lines)]
|
|
return point.Shading, point.Corners[:]
|
|
}
|
|
|
|
// meshDeclaration 读取完整基础网格声明，不将渐进网格当作完整模型
|
|
// 入参: r 字段读取器, name 网格名
|
|
// 返回: error 结构、能力或预算错误
|
|
func (d *u3dDecoder) meshDeclaration(r *u3dValues, name string) error {
|
|
if _, exists := d.meshes[name]; exists {
|
|
return fmt.Errorf("duplicate U3D mesh %q", name)
|
|
}
|
|
index, attributes := r.u32(), r.u32()
|
|
if index != 0 || attributes > 1 {
|
|
return fmt.Errorf("invalid U3D mesh declaration")
|
|
}
|
|
decl := &u3dMeshDeclaration{mesh: U3DMesh{Name: name, ExcludeNormals: attributes == 1}}
|
|
for index := range decl.counts {
|
|
decl.counts[index] = r.u32()
|
|
}
|
|
if err := d.meshShadings(r, decl); err != nil {
|
|
return err
|
|
}
|
|
minimum, maximum := r.u32(), r.u32()
|
|
for index := range decl.mesh.Quality {
|
|
decl.mesh.Quality[index] = r.u32()
|
|
}
|
|
for index := range decl.mesh.InverseQuantization {
|
|
decl.mesh.InverseQuantization[index] = r.f32()
|
|
}
|
|
decl.mesh.NormalCrease, decl.mesh.NormalUpdate, decl.mesh.NormalTolerance = r.f32(), r.f32(), r.f32()
|
|
if r.err != nil {
|
|
return r.err
|
|
}
|
|
if minimum > maximum || maximum != decl.counts[1] {
|
|
return fmt.Errorf("invalid U3D mesh resolution")
|
|
}
|
|
if minimum != maximum {
|
|
return fmt.Errorf("unsupported U3D progressive mesh")
|
|
}
|
|
bones, err := d.skeleton(r)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
decl.mesh.Bones = bones
|
|
if minimum == 0 {
|
|
for _, count := range decl.counts[:6] {
|
|
if count != 0 {
|
|
return fmt.Errorf("invalid U3D empty mesh")
|
|
}
|
|
}
|
|
}
|
|
d.meshes[name] = decl
|
|
d.meshOrder = append(d.meshOrder, name)
|
|
return nil
|
|
}
|
|
|
|
// meshShadings 读取三角面与线集共用的着色描述
|
|
// 入参: r 字段读取器, decl 资源声明
|
|
// 返回: error 结构或预算错误
|
|
func (d *u3dDecoder) meshShadings(r *u3dValues, decl *u3dMeshDeclaration) error {
|
|
if r.err != nil {
|
|
return r.err
|
|
}
|
|
count := decl.counts[6]
|
|
if uint64(count) > uint64(len(r.data)-r.pos)/12 {
|
|
return io.ErrUnexpectedEOF
|
|
}
|
|
if err := d.reserve(uint64(count), 40); err != nil {
|
|
return err
|
|
}
|
|
decl.mesh.Shadings = make([]U3DShading, int(count))
|
|
for index := range decl.mesh.Shadings {
|
|
shading := &decl.mesh.Shadings[index]
|
|
shading.Attributes = r.u32()
|
|
layers := r.u32()
|
|
if shading.Attributes > 3 {
|
|
return fmt.Errorf("invalid U3D shading attributes")
|
|
}
|
|
if layers > 8 {
|
|
return fmt.Errorf("unsupported U3D texture layer count")
|
|
}
|
|
if err := d.reserve(uint64(layers), 4); err != nil {
|
|
return err
|
|
}
|
|
shading.TextureDimensions = make([]uint32, int(layers))
|
|
for layer := range shading.TextureDimensions {
|
|
dimension := r.u32()
|
|
if dimension < 1 || dimension > 4 {
|
|
return fmt.Errorf("invalid U3D texture coordinate dimension")
|
|
}
|
|
shading.TextureDimensions[layer] = dimension
|
|
}
|
|
shading.OriginalID = r.u32()
|
|
}
|
|
return r.err
|
|
}
|
|
|
|
// baseMesh 读取基础顶点与压缩面索引，保留各角点的独立属性
|
|
// 入参: r 字段读取器, name 网格名
|
|
// 返回: error 结构、能力、预算或取消错误
|
|
func (d *u3dDecoder) baseMesh(r *u3dValues, name string) error {
|
|
decl := d.meshes[name]
|
|
if decl == nil || decl.line != nil || decl.decoded || decl.counts[1] == 0 || r.u32() != 0 {
|
|
return fmt.Errorf("invalid U3D base mesh reference")
|
|
}
|
|
var counts [6]uint32
|
|
for index := range counts {
|
|
counts[index] = r.u32()
|
|
if counts[index] != decl.counts[index] {
|
|
return fmt.Errorf("U3D base mesh does not match full resolution declaration")
|
|
}
|
|
}
|
|
if r.err != nil {
|
|
return r.err
|
|
}
|
|
literalBytes := (uint64(counts[1])+uint64(counts[2]))*12 + (uint64(counts[3])+uint64(counts[4])+uint64(counts[5]))*16
|
|
if literalBytes > uint64(len(r.data)-r.pos) {
|
|
return io.ErrUnexpectedEOF
|
|
}
|
|
if err := d.reserve(literalBytes, 1); err != nil {
|
|
return err
|
|
}
|
|
if err := d.reserve(uint64(counts[0]), 148); err != nil {
|
|
return err
|
|
}
|
|
mesh := &decl.mesh
|
|
mesh.Positions, mesh.Normals = make([][3]float32, int(counts[1])), make([][3]float32, int(counts[2]))
|
|
mesh.Diffuse, mesh.Specular, mesh.TextureCoordinates = make([][4]float32, int(counts[3])), make([][4]float32, int(counts[4])), make([][4]float32, int(counts[5]))
|
|
for _, array := range [][][3]float32{mesh.Positions, mesh.Normals} {
|
|
for index := range array {
|
|
if index%1024 == 0 {
|
|
if r.err != nil {
|
|
return r.err
|
|
}
|
|
if err := d.ctx.Err(); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
for component := range array[index] {
|
|
array[index][component] = r.f32()
|
|
}
|
|
}
|
|
}
|
|
for _, array := range [][][4]float32{mesh.Diffuse, mesh.Specular, mesh.TextureCoordinates} {
|
|
for index := range array {
|
|
if index%1024 == 0 {
|
|
if r.err != nil {
|
|
return r.err
|
|
}
|
|
if err := d.ctx.Err(); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
for component := range array[index] {
|
|
array[index][component] = r.f32()
|
|
}
|
|
}
|
|
}
|
|
if r.err != nil {
|
|
return r.err
|
|
}
|
|
mesh.Faces = make([]U3DFace, int(counts[0]))
|
|
var histogram u3dHistogram
|
|
var compressed *u3dBits
|
|
if !d.plain && counts[0] != 0 {
|
|
compressed = newU3DBits(r.data[r.pos:])
|
|
var charged uint64
|
|
compressed.reserve = func(count, size uint64) error {
|
|
if err := d.reserve(count, size); err != nil {
|
|
return err
|
|
}
|
|
charged += count * size
|
|
return nil
|
|
}
|
|
defer func() { d.remaining += charged }()
|
|
}
|
|
readIndex := func(count uint32) (uint32, error) {
|
|
var value uint32
|
|
if compressed == nil {
|
|
value = r.u32()
|
|
} else {
|
|
value = compressed.index(count)
|
|
if compressed.err != nil {
|
|
return 0, compressed.err
|
|
}
|
|
}
|
|
if r.err != nil {
|
|
return 0, r.err
|
|
}
|
|
if value >= count {
|
|
return 0, fmt.Errorf("invalid U3D corner index")
|
|
}
|
|
return value, nil
|
|
}
|
|
for index := range mesh.Faces {
|
|
if index%256 == 0 {
|
|
if err := d.ctx.Err(); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
face := &mesh.Faces[index]
|
|
if compressed == nil {
|
|
face.Shading = r.u32()
|
|
} else {
|
|
face.Shading = compressed.dynamic(&histogram)
|
|
if compressed.err != nil {
|
|
return compressed.err
|
|
}
|
|
}
|
|
if r.err != nil {
|
|
return r.err
|
|
}
|
|
if uint64(face.Shading) >= uint64(len(mesh.Shadings)) {
|
|
return fmt.Errorf("invalid U3D face shading index")
|
|
}
|
|
shading := &mesh.Shadings[face.Shading]
|
|
for cornerIndex := range face.Corners {
|
|
corner := &face.Corners[cornerIndex]
|
|
var err error
|
|
if corner.Position, err = readIndex(counts[1]); err != nil {
|
|
return err
|
|
}
|
|
if !mesh.ExcludeNormals {
|
|
if corner.Normal, err = readIndex(counts[2]); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
if shading.Attributes&1 != 0 {
|
|
if corner.Diffuse, err = readIndex(counts[3]); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
if shading.Attributes&2 != 0 {
|
|
if corner.Specular, err = readIndex(counts[4]); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
for layer := range shading.TextureDimensions {
|
|
if corner.Texture[layer], err = readIndex(counts[5]); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if compressed != nil {
|
|
if err := compressed.finish(); err != nil {
|
|
return err
|
|
}
|
|
r.pos = len(r.data)
|
|
}
|
|
decl.decoded = true
|
|
return r.done()
|
|
}
|