public void DrawFace(WavefrontObject meshObj, WavefrontFace face, Shader shader)
{
//WavefontFace是一个triangle fan
//可能会有多个三角形;这些三角形共用第一个顶点做v0
if (face.Vertices.Count < 3)
{
Debug.Assert(false);
return;
}
Vertex vertex0 = Vertex.FromWavefrontVertex(meshObj, face.Vertices[0]);
VSOutput vClip0 = shader.VertShader(vertex0);
context.statics.vertexCount += 1;
for (int i = 1; i + 1 < face.Vertices.Count; i += 1)
{
Vertex vertex1 = Vertex.FromWavefrontVertex(meshObj, face.Vertices[i]);
Vertex vertex2 = Vertex.FromWavefrontVertex(meshObj, face.Vertices[i + 1]);
//顶点着色器
VSOutput vClip1 = shader.VertShader(vertex1);
VSOutput vClip2 = shader.VertShader(vertex2);
context.statics.vertexCount += 2;
DrawTriangle(vClip0, vClip1, vClip2);
}
}
//材质
//public static Material mat = new Material(new Color(0, 0, 0.1f), 0.1f, new Color(0.3f, 0.3f, 0.3f), new Color(1, 1, 1), 99);
public static WavefrontObject ToWavefrontObject()
{
WavefrontObject obj = new WavefrontObject();
for (int i = 0; i < CubeTestData.pointList.Length; ++i)
{
Vector3 point = CubeTestData.pointList[i];
obj.Positions.Add(point);
}
for (int i = 0; i < CubeTestData.normals.Length; ++i)
{
Vector3 normal = CubeTestData.normals[i];
obj.Normals.Add(normal);
}
for (int i = 0; i < CubeTestData.uvs.Length; ++i)
{
Vector2 uv = CubeTestData.uvs[i];
obj.Texcoords.Add(uv);
}
for (int i = 0; i < CubeTestData.vertColors.Length; ++i)
{
Vector4 color = new Vector4(CubeTestData.vertColors[i], 1);
obj.Colors.Add(color);
}
//处理三角形
WavefrontFaceGroup faceGroup = new WavefrontFaceGroup();
obj.Groups.Add(faceGroup);
for (int i = 0; i + 2 < CubeTestData.indexs.Length; i += 3)
{
WavefrontFace face = new WavefrontFace();
faceGroup.Faces.Add(face);
int index0 = i;
int index1 = i + 1;
int index2 = i + 2;
int p0 = CubeTestData.indexs[i];
int p1 = CubeTestData.indexs[i + 1];
int p2 = CubeTestData.indexs[i + 2];
WavefrontVertex v0 = new WavefrontVertex(p0 + 1, index0 + 1, index0 + 1);
WavefrontVertex v1 = new WavefrontVertex(p1 + 1, index1 + 1, index1 + 1);
WavefrontVertex v2 = new WavefrontVertex(p2 + 1, index2 + 1, index2 + 1);
v0.Color = index0 + 1;
v1.Color = index1 + 1;
v2.Color = index2 + 1;
face.Vertices.Add(v0);
face.Vertices.Add(v1);
face.Vertices.Add(v2);
}
return(obj);
}