public void Start()
{
camera = new Camera();
draw = new DrawString();
input = new Thread(ManageInput);
input.Start();
// Perspective Projection
/*Sources:
* https://stackoverflow.com/questions/53245632/general-formula-for-perspective-projection-matrix
* https://www.scratchapixel.com/lessons/3d-basic-rendering/perspective-and-orthographic-projection-matrix/building-basic-perspective-projection-matrix
*/
float fovRad = 1.0f / (float)Math.Tan(camera.Fov * 0.5f * (Math.PI / 180.0f));
perspProjection = new float[4, 4] {
{ fovRad *ASPECT_RATIO, 0, 0, 0 },
{ 0, fovRad, 0, 0 },
{ 0, 0, -camera.FarPlane / (camera.FarPlane - camera.NearPlane), -(camera.FarPlane * camera.NearPlane) / (camera.FarPlane - camera.NearPlane) },
{ 0, 0, 1, 0 }
};
// ######################
}
private Mat4x4 GetViewMatrix()
{
float cosPitch = (float)Math.Cos(Pitch * (Math.PI / 180.0f));
float sinPitch = (float)Math.Sin(Pitch * (Math.PI / 180.0f));
float cosYaw = (float)Math.Cos(Yaw * (Math.PI / 180.0f));
float sinYaw = (float)Math.Sin(Yaw * (Math.PI / 180.0f));
float cosRoll = (float)Math.Cos(Roll * (Math.PI / 180.0f));
float sinRoll = (float)Math.Sin(Roll * (Math.PI / 180.0f));
Mat4x4 rotX = new float[4, 4] {
{ 1, 0, 0, 0 },
{ 0, cosPitch, -sinPitch, 0 },
{ 0, sinPitch, cosPitch, 0 },
{ 0, 0, 0, 1 }
};
Mat4x4 rotY = new float[4, 4] {
{ cosYaw, 0, sinYaw, 0 },
{ 0, 1, 0, 0 },
{ -sinYaw, 0, cosYaw, 0 },
{ 0, 0, 0, 1 }
};
Mat4x4 rotZ = new float[4, 4] {
{ cosRoll, -sinRoll, 0, 0 },
{ sinRoll, cosRoll, 0, 0 },
{ 0, 0, 1, 0 },
{ 0, 0, 0, 1 }
};
Mat4x4 camRot = Mat4x4.MatMul(rotZ, rotY);
camRot = Mat4x4.MatMul(camRot, rotX);
Vector up = new Vector(0, 1, 0);
Vector target = new Vector(0, 0, 1);
Vector lookDir = Mat4x4.MatMul(target, camRot);
target = Position + lookDir;
return(LookAt(Position, target, up));
}
// https://learnopengl.com/Getting-started/Camera
public Mat4x4 LookAt(Vector worldPos, Vector targetPos, Vector newUp)
{
Forward = (targetPos - worldPos).Normalized;
Up = (newUp - (Forward * Vector.DotProduct(newUp, Forward))).Normalized;
Right = Vector.CrossProduct(Up, Forward);
Mat4x4 rotation = new float[4, 4] {
{ Right.X, Right.Y, Right.Z, 0 },
{ Up.X, Up.Y, Up.Z, 0 },
{ Forward.X, Forward.Y, Forward.Z, 0 },
{ 0, 0, 0, 1 }
};
Mat4x4 translation = new float[4, 4] {
{ 1, 0, 0, -Position.X },
{ 0, 1, 0, -Position.Y },
{ 0, 0, 1, -Position.Z },
{ 0, 0, 0, 1 }
};
return(Mat4x4.MatMul(rotation, translation));
}
// Render 3D Objects
private void Render3D()
{
//Mat4x4 camTranform = Mat4x4.MatMul(Mat4x4.VecToMat(camera.Position), Mat4x4.VecToMat())
Light simpleLight = new Light {
Direction = new Vector(0, 0, 1)
};
simpleLight.Direction.Normalize();
Mat4x4 rotationX = new float[4, 4] {
{ 1, 0, 0, 0 },
{ 0, (float)Math.Cos(xAngle), (float)-Math.Sin(xAngle), 0 },
{ 0, (float)Math.Sin(xAngle), (float)Math.Cos(xAngle), 0 },
{ 0, 0, 0, 1 }
};
Mat4x4 rotationY = new float[4, 4] {
{ (float)Math.Cos(yAngle), 0, (float)Math.Sin(yAngle), 0 },
{ 0, 1, 0, 0 },
{ (float)-Math.Sin(yAngle), 0, (float)Math.Cos(yAngle), 0 },
{ 0, 0, 0, 1 }
};
Mat4x4 rotationZ = new float[4, 4] {
{ (float)Math.Cos(zAngle), (float)-Math.Sin(zAngle), 0, 0 },
{ (float)Math.Sin(zAngle), (float)Math.Cos(zAngle), 0, 0 },
{ 0, 0, 1, 0 },
{ 0, 0, 0, 1 }
};
// XYZ rotation = (((Z * Y) * X) * Vector) or (Z×Y×X)×V
Mat4x4 rotMatrix = Mat4x4.MatMul(rotationZ, rotationY);
rotMatrix = Mat4x4.MatMul(rotMatrix, rotationX);
Mat4x4 mvp = ortho ? Mat4x4.MatMul(orthoProjection, camera.ViewMatrix) : Mat4x4.MatMul(perspProjection, camera.ViewMatrix);
Triangle[] updatedTri = new Triangle[mesh.Polygons.Length];
for (int i = 0; i < mesh.Polygons.Length; i++)
{
updatedTri[i] = new Triangle(new Vector[mesh.Polygons[i].VertexCount]);
for (int j = 0; j < mesh.Polygons[i].VertexCount; j++)
{
// Apply rotation to vertex
Vector rotated = Mat4x4.MatMul(mesh.Polygons[i][j], rotMatrix);
// Translate vertex (slightly) to not draw on top of camera
Vector translated = new Vector(rotated.X, rotated.Y, rotated.Z + 3.0f);
updatedTri[i][j] = translated;
}
float lightDP = Math.Max(0.1f, Vector.DotProduct(updatedTri[i].Normal, simpleLight.Direction));
ShadeTri(ref updatedTri[i], lightDP);
}
Triangle[] projected = new Triangle[mesh.Polygons.Length];
for (int i = 0; i < projected.Length; i++)
{
projected[i] = updatedTri[i];
for (int j = 0; j < projected[i].VertexCount; j++)
{
projected[i][j] = Mat4x4.MatMul(projected[i][j], mvp);
// Scale Vectors
projected[i][j] *= ortho ? 20.0f : projectionScale; // Magic numbers :(
}
}
if (rotate)
{
if (rotateX)
{
xAngle -= 0.03f;
}
if (rotateY)
{
yAngle -= 0.03f;
}
if (rotateZ)
{
zAngle -= 0.03f;
}
}
if (hasMesh && hasSurface)
{
// Plot Faces and Mesh
// After testing with modified versions of the methods below
// it's safe to assume this needs its own method
// If implementation becomes unnecessary, remove this
}
else if (hasSurface)
{
draw.PlotFaces(projected);
}
else if (hasMesh)
{
draw.PlotMesh(projected);
}
else
{
draw.PlotVertices(projected);
}
}