我试图使边界使用矩形sdf，但与不同的规模，它得到扭曲。
我在考虑对象比例，但我自己不知道该怎么做
对象比例：（1，1），（1，0.125）
How it looks
Desired result (Made in photoshop, slightly out of proportion)
有顶点，片段着色器和矩形函数

float rectangle(float2 position, float2 size){
    float2 component_wise_edge_distance = abs(position) - size;
    float outside_distance = length(max(component_wise_edge_distance, 0));
    float inside_distance = min(max(component_wise_edge_distance.x, component_wise_edge_distance.y), 0);
    return outside_distance + inside_distance;
}

v2f vert(appdata v){
    v2f o;
    o.position = UnityObjectToClipPos(v.vertex);
    o.uv = v.uv;
    return o;
}

float4 frag(v2f i) : SV_TARGET
{
    half3x3 m = UNITY_MATRIX_M;
    half3 objectScale = half3(
        length( half3( m[0][0], m[1][0], m[2][0] ) ),
        length( half3( m[0][1], m[1][1], m[2][1] ) ),
        length( half3( m[0][2], m[1][2], m[2][2] ) )
    );
    
    float4 coords = i.uv;
    coords *= 8;

    float2 position = float2(coords.x - 4, coords.y - 4);
    float sdf = step(0, rectangle(position, float2(3, 3)));
    
    float4 col = float4(sdf.xxx, 1);
    return col;
}