qmuntal/gltf

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binary/slice.go

Summary

Maintainability
A
3 hrs
Test Coverage
package binary

import (
    "fmt"
    "image/color"
    "reflect"

    "github.com/qmuntal/gltf"
)

// MakeSliceBuffer returns the slice type associated with c and t and with the given element count.
// If the buffer is an slice which type matches with the expected by the acr then it will
// be used as backing slice.
func MakeSliceBuffer(c gltf.ComponentType, t gltf.AccessorType, count uint32, buffer interface{}) interface{} {
    if buffer == nil {
        return MakeSlice(c, t, count)
    }
    c1, t1, count1 := Type(buffer)
    if count1 == 0 || c1 != c || t1 != t {
        return MakeSlice(c, t, count)
    }
    if count1 < count {
        tmpSlice := MakeSlice(c, t, count-count1)
        return reflect.AppendSlice(reflect.ValueOf(buffer), reflect.ValueOf(tmpSlice)).Interface()
    }
    if count1 > count {
        return reflect.ValueOf(buffer).Slice(0, int(count)).Interface()
    }
    return buffer
}

// MakeSlice returns the slice type associated with c and t and with the given element count.
// For example, if c is gltf.ComponentFloat and t is gltf.AccessorVec3
// then MakeSlice(c, t, 5) is equivalent to make([][3]float32, 5).
func MakeSlice(c gltf.ComponentType, t gltf.AccessorType, count uint32) interface{} {
    var tp reflect.Type
    switch c {
    case gltf.ComponentUbyte:
        tp = reflect.TypeOf((*uint8)(nil))
    case gltf.ComponentByte:
        tp = reflect.TypeOf((*int8)(nil))
    case gltf.ComponentUshort:
        tp = reflect.TypeOf((*uint16)(nil))
    case gltf.ComponentShort:
        tp = reflect.TypeOf((*int16)(nil))
    case gltf.ComponentUint:
        tp = reflect.TypeOf((*uint32)(nil))
    case gltf.ComponentFloat:
        tp = reflect.TypeOf((*float32)(nil))
    }
    tp = tp.Elem()
    switch t {
    case gltf.AccessorVec2:
        tp = reflect.ArrayOf(2, tp)
    case gltf.AccessorVec3:
        tp = reflect.ArrayOf(3, tp)
    case gltf.AccessorVec4:
        tp = reflect.ArrayOf(4, tp)
    case gltf.AccessorMat2:
        tp = reflect.ArrayOf(2, reflect.ArrayOf(2, tp))
    case gltf.AccessorMat3:
        tp = reflect.ArrayOf(3, reflect.ArrayOf(3, tp))
    case gltf.AccessorMat4:
        tp = reflect.ArrayOf(4, reflect.ArrayOf(4, tp))
    }
    return reflect.MakeSlice(reflect.SliceOf(tp), int(count), int(count)).Interface()
}

// Type returns the associated glTF type data.
// It panics if data is not an slice.
func Type(data interface{}) (c gltf.ComponentType, t gltf.AccessorType, count uint32) {
    v := reflect.ValueOf(data)
    if v.Kind() != reflect.Slice {
        panic(fmt.Sprintf("go3mf: binary.Type expecting a slice but got %s", v.Kind()))
    }
    count = uint32(v.Len())
    switch data.(type) {
    case []int8:
        c, t = gltf.ComponentByte, gltf.AccessorScalar
    case [][2]int8:
        c, t = gltf.ComponentByte, gltf.AccessorVec2
    case [][3]int8:
        c, t = gltf.ComponentByte, gltf.AccessorVec3
    case [][4]int8:
        c, t = gltf.ComponentByte, gltf.AccessorVec4
    case [][2][2]int8:
        c, t = gltf.ComponentByte, gltf.AccessorMat2
    case [][3][3]int8:
        c, t = gltf.ComponentByte, gltf.AccessorMat3
    case [][4][4]int8:
        c, t = gltf.ComponentByte, gltf.AccessorMat4
    case []uint8:
        c, t = gltf.ComponentUbyte, gltf.AccessorScalar
    case [][2]uint8:
        c, t = gltf.ComponentUbyte, gltf.AccessorVec2
    case [][3]uint8:
        c, t = gltf.ComponentUbyte, gltf.AccessorVec3
    case []color.RGBA, [][4]uint8:
        c, t = gltf.ComponentUbyte, gltf.AccessorVec4
    case [][2][2]uint8:
        c, t = gltf.ComponentUbyte, gltf.AccessorMat2
    case [][3][3]uint8:
        c, t = gltf.ComponentUbyte, gltf.AccessorMat3
    case [][4][4]uint8:
        c, t = gltf.ComponentUbyte, gltf.AccessorMat4
    case []int16:
        c, t = gltf.ComponentShort, gltf.AccessorScalar
    case [][2]int16:
        c, t = gltf.ComponentShort, gltf.AccessorVec2
    case [][3]int16:
        c, t = gltf.ComponentShort, gltf.AccessorVec3
    case [][4]int16:
        c, t = gltf.ComponentShort, gltf.AccessorVec4
    case [][2][2]int16:
        c, t = gltf.ComponentShort, gltf.AccessorMat2
    case [][3][3]int16:
        c, t = gltf.ComponentShort, gltf.AccessorMat3
    case [][4][4]int16:
        c, t = gltf.ComponentShort, gltf.AccessorMat4
    case []uint16:
        c, t = gltf.ComponentUshort, gltf.AccessorScalar
    case [][2]uint16:
        c, t = gltf.ComponentUshort, gltf.AccessorVec2
    case [][3]uint16:
        c, t = gltf.ComponentUshort, gltf.AccessorVec3
    case []color.RGBA64, [][4]uint16:
        c, t = gltf.ComponentUshort, gltf.AccessorVec4
    case [][2][2]uint16:
        c, t = gltf.ComponentUshort, gltf.AccessorMat2
    case [][3][3]uint16:
        c, t = gltf.ComponentUshort, gltf.AccessorMat3
    case [][4][4]uint16:
        c, t = gltf.ComponentUshort, gltf.AccessorMat4
    case []uint32:
        c, t = gltf.ComponentUint, gltf.AccessorScalar
    case [][2]uint32:
        c, t = gltf.ComponentUint, gltf.AccessorVec2
    case [][3]uint32:
        c, t = gltf.ComponentUint, gltf.AccessorVec3
    case [][4]uint32:
        c, t = gltf.ComponentUint, gltf.AccessorVec4
    case [][2][2]uint32:
        c, t = gltf.ComponentUint, gltf.AccessorMat2
    case [][3][3]uint32:
        c, t = gltf.ComponentUint, gltf.AccessorMat3
    case [][4][4]uint32:
        c, t = gltf.ComponentUint, gltf.AccessorMat4
    case []float32:
        c, t = gltf.ComponentFloat, gltf.AccessorScalar
    case [][2]float32:
        c, t = gltf.ComponentFloat, gltf.AccessorVec2
    case [][3]float32:
        c, t = gltf.ComponentFloat, gltf.AccessorVec3
    case [][4]float32:
        c, t = gltf.ComponentFloat, gltf.AccessorVec4
    case [][2][2]float32:
        c, t = gltf.ComponentFloat, gltf.AccessorMat2
    case [][3][3]float32:
        c, t = gltf.ComponentFloat, gltf.AccessorMat3
    case [][4][4]float32:
        c, t = gltf.ComponentFloat, gltf.AccessorMat4
    default:
        panic(fmt.Sprintf("go3mf: binary.Type expecting a glTF supported type but got %s", v.Kind()))
    }
    return
}