/// <summary>
/// 法线映射
/// </summary>
/// <param name="vertex"></param>
/// <returns></returns>
public Color01 NormalMappingWithLambert(Vertex vertex, Mesh mesh, Light light)
{
// 从法线贴图中取出法线(切线空间下的)
Color01 UndecryptedNormal = Texture.Tex2D(normalTexture, vertex.u, vertex.v);
// 把法线从[0,1]区间变回到[-1,1]区间
Vector3 normal = new Vector3(
UndecryptedNormal.R * 2 - 1,
UndecryptedNormal.G * 2 - 1,
UndecryptedNormal.B * 2 - 1
);
// 获得世界坐标下的法线
Vector3 worldNormal = mesh.mMatrix * vertex.normal;
worldNormal.Normlize();
// 获得世界坐标下的切线
Vector3 worldTangent = mesh.mMatrix * vertex.tangent;
worldTangent.Normlize();
// 获得世界坐标下的副切线
Vector3 worldBinormal = Vector3.Cross(worldNormal, worldTangent) * vertex.tangent.W;
worldBinormal.Normlize();
// 构建 切线-世界 变换矩阵
Matrix4x4 TtoW = new Matrix4x4();
TtoW.Identity();
TtoW.value[0, 0] = worldTangent.X;
TtoW.value[1, 0] = worldTangent.Y;
TtoW.value[2, 0] = worldTangent.Z;
TtoW.value[0, 1] = worldBinormal.X;
TtoW.value[1, 1] = worldBinormal.Y;
TtoW.value[2, 1] = worldBinormal.Z;
TtoW.value[0, 2] = worldNormal.X;
TtoW.value[1, 2] = worldNormal.Y;
TtoW.value[2, 2] = worldNormal.Z;
// 将切线空间的法线变为世界坐标
normal = TtoW * normal;
normal.Normlize();
// 增大凹凸比例
normal.X *= 3;
normal.Y *= 3;
normal.Z *= MathF.Sqrt(1 - MathF.Clamp01(normal.X * normal.X + normal.Y * normal.Y));
Color01 albedo = Texture.Tex2D(texture2D, vertex.u, vertex.v) * vertex.color;
Vector3 worldPos = mesh.mMatrix * vertex.modelSpacePos;
float radiance = Vector3.Dot(normal, light.GetDirection(worldPos)) * 0.5f + 0.5f;
Color01 diffuse = albedo * radiance;
return(diffuse);
}
private static void ClampVectorComponents(ref Vector4 v)
{
v.X = MathF.Clamp01(v.X);
v.Y = MathF.Clamp01(v.Y);
v.Z = MathF.Clamp01(v.Z);
v.W = MathF.Clamp01(v.W);
}
[Test] public void Clamp01Checks()
{
Assert.AreEqual(MathF.Clamp01(-0.0f), 0.0f, Epsilon);
Assert.AreEqual(MathF.Clamp01(0.0f), 0.0f, Epsilon);
Assert.AreEqual(MathF.Clamp01(0.001f), 0.001f, Epsilon);
Assert.AreEqual(MathF.Clamp01(1.0001f), 1.0f, Epsilon);
Assert.AreEqual(MathF.Clamp01(1.0f), 1.0f, Epsilon);
Assert.AreEqual(MathF.Clamp01(0.999f), 0.999f, Epsilon);
Assert.AreEqual(MathF.Clamp01(0.567f), 0.567f, Epsilon);
}
public override float GetAtten(Vector3 targetPosition)
{
// θ,片元指向光源的方向与聚光灯朝向的夹角(cos)
float cosTheta = Vector3.Dot(-GetDirection(targetPosition).normlize, spotDir.normlize);
// Epsilon是内外圆锥的余弦差值
float epsilon = cosInnerAngle - cosPhi;
// 聚光灯强度
float intensity = MathF.Clamp01((cosTheta - cosPhi) / epsilon);
return(intensity);
}
public override void Draw(IDrawDevice device)
{
if (_sprites == null)
{
return;
}
float warpTime = MathF.Max(MinWarpTime, WarpTime);
float chargeTime = MathF.Max(MinChargeTime, ChargeTime);
if (ElapsedTime < chargeTime)
{
float alpha = MathF.Clamp01(ElapsedTime / chargeTime);
foreach (var sprite in _sprites)
{
SpriteGlowEffect.RenderSpriteGlow(device, sprite, GlowType.Position | GlowType.Scale, 1.1f, 10f, Color.WithAlpha(alpha), DrawTechnique.Res, -100);
}
foreach (var geom in _geometries)
{
SpriteGlowEffect.RenderSpriteGlow(device, geom, GlowType.Position | GlowType.Scale, 1.1f, 10f, Color.WithAlpha(alpha), DrawTechnique.Res, -100);
}
}
else if (ElapsedTime >= chargeTime && ElapsedTime <= chargeTime + warpTime)
{
foreach (var spr in _sprites)
{
spr.Active = false;
}
var vel = 100f;
var vector = Ship.Transform.GetWorldVector(new Vector2(vel, 0));
var rb = Ship.GetComponent <RigidBody>();
rb.Active = false;
//rb.ApplyLocalForce(vector * rb.Mass);
Ship.Transform.Pos += new Vector3(vector, Ship.Transform.Pos.Z);
float alpha = 1f - MathF.Clamp01((ElapsedTime - chargeTime) / warpTime);
foreach (var sprite in _sprites)
{
SpriteGlowEffect.RenderSpriteGlow(device, sprite, GlowType.Position | GlowType.Scale, 1.1f, 10f, Color.WithAlpha(alpha), DrawTechnique.Res, -100);
}
foreach (var geom in _geometries)
{
SpriteGlowEffect.RenderSpriteGlow(device, geom, GlowType.Position | GlowType.Scale, 1.1f, 10f, Color.WithAlpha(alpha), DrawTechnique.Res, -100);
}
}
else
{
_isWarpDone = true;
}
ElapsedTime += Time.DeltaTime;
}
/// <summary>
/// 山寨版片元着色器，
/// 根据一个顶点的各属性，计算当前顶点（屏幕空间下）的像素的颜色
/// </summary>
/// <param name="vertex"></param>
/// <returns></returns>
public Color01 FragmentShader(Vertex vertex)
{
// 基于半兰伯特光照模型的光照
//return LightingWithLambert(vertex);
// 从法线贴图中取出法线(切线空间下的)
Color01 UndecryptedNormal = Texture.Tex2D(normalTexture, vertex.u, vertex.v);
// 把法线从[0,1]区间变回到[-1,1]区间
Vector3 normal = new Vector3(
UndecryptedNormal.R * 2 - 1,
UndecryptedNormal.G * 2 - 1,
UndecryptedNormal.B * 2 - 1
);
// 获得世界坐标下的法线
Vector3 worldNormal = vertex.mMatrix * vertex.normal;
worldNormal.Normlize();
// 获得世界坐标下的切线
Vector3 worldTangent = vertex.mMatrix * vertex.tangent;
worldTangent.Normlize();
// 获得世界坐标下的副切线
Vector3 worldBinormal = Vector3.Cross(worldNormal, worldTangent) * vertex.tangent.W;
worldBinormal.Normlize();
// 构建 切线-世界 变换矩阵
Matrix4x4 TtoW = new Matrix4x4();
TtoW.Identity();
TtoW.value[0, 0] = worldTangent.X;
TtoW.value[1, 0] = worldTangent.Y;
TtoW.value[2, 0] = worldTangent.Z;
TtoW.value[0, 1] = worldBinormal.X;
TtoW.value[1, 1] = worldBinormal.Y;
TtoW.value[2, 1] = worldBinormal.Z;
TtoW.value[0, 2] = worldNormal.X;
TtoW.value[1, 2] = worldNormal.Y;
TtoW.value[2, 2] = worldNormal.Z;
// 将切线空间的法线变为世界坐标
normal = TtoW * normal;
normal.Normlize();
// 增大凹凸比例
normal.X *= 3;
normal.Y *= 3;
normal.Z *= MathF.Sqrt(1 - MathF.Clamp01(normal.X * normal.X + normal.Y * normal.Y));
Color01 albedo = Texture.Tex2D(texture2D, vertex.u, vertex.v);
float radiance = Vector3.Dot(normal, DirectionLight) * 0.5f + 0.5f;
Color01 diffuse = albedo * radiance;
return(diffuse);
}