cgeimg::float[ weapon_camera_child.png|Camera preview\, with weapon as camera child ]

Introduction

Camera determines what do you see in the viewport. Camera is a cgeref:TCastleTransform[] descendant, and as such it defines:

cgeref:TCastleTransform.Translation[] - observer position.
cgeref:TCastleTransform.Direction[] - direction in which you look.
cgeref:TCastleTransform.Up[] - together with direction, the up vector determines the camera orientation.

A common way to set all camera vectors is to use cgeref:TCastleTransform.SetView[].

Camera also defines projection:

cgeref:TCastleCamera.ProjectionType[] - determines perspective or orthographic projection.
cgeref:TCastleCamera.Perspective[], cgeref:TCastleCamera.Orthographic[] - these subcomponents allow to configure projection details.

The initial camera

There are various ways to set the initial camera:

If you design your world using the Castle Game Engine editor, we recommend to set the initial camera following the Tutorial: Designing a 3D world. This means that you just move / rotate the camera as any other cgeref:TCastleTransform[].
Another approach is to just set the camera vectors by code during your view start. Call cgeref:TCastleTransform.SetView[Viewport.Camera.SetView] like this:
```
Viewport.Camera.SetView(
  Vector3(-11.34, 30.04, 96.07), // position
  Vector3(0.10, -0.49, -0.87), // direction
  Vector3(0.35, 0.83, -0.43), // up (current)
  Vector3(0.00, 1.00, 0.00) // gravity up
);
```
You can even generate such Pascal code: Use the "Clipboard → Print Current Camera (Viewpoint) (Pascal)" menu item in Castle Model Viewer.
Alternatively, automatically initialize the camera defaults (including position, direction, up vectors) based on the information in the model.

To activate this auto-detection, set cgeref:TCastleViewport.AutoCamera[] to true.

The way this auto-detection works:
- If the scene set as cgeref:TCastleRootTransform.MainScene[Viewport.Items.MainScene] defines a default camera, then use it.
  
  For example glTF format allows to define a default camera. Blender can export such glTF models.
  
  Models in In X3D can also define a default camera, using X3D Viewpoint or OrthoViewpoint nodes. If you write X3D files by hand, you can even generate such nodes using the "Clipboard → Print Current Camera (Viewpoint)" menu item in Castle Model Viewer.
- Otherwise (if there is no Viewpoint node,or you didn’t even set MainScene) then the camera will be auto-detected to look at the world bounding box.

Camera can have children, and be a child of other objects

Since camera is a cgeref:TCastleTransform[] descendant:

Camera can be a child of another cgeref:TCastleTransform[].
- For example you can attach a camera to some object (like a car or character) to move camera along with that object.
- You can combine this with cgeref:TCastleSceneCore.ExposeTransforms[ExposeTransforms] to attach a camera to an animated bone of your character.
Camera can have other cgeref:TCastleTransform[] as children.
- For example you can attach a weapon carried by a player in FPS game as a child of camera. See examples/3d_games/explore_impressive_castle demo.
- You can make a headlight by simply placing a light (like cgeref:TCastleDirectionalLight[]) as camera child. See examples/viewport_and_scenes/headlight demo.

When the camera is a child of other objects, you have to be careful when controlling camera translation / rotation from code.

Use cgeref:TCastleTransform.GetView[], cgeref:TCastleTransform.SetView[] to get / set camera vectors in the local coordinate system.
Use cgeref:TCastleTransform.GetWorldView[], cgeref:TCastleTransform.SetWorldView[] to get / set camera vectors in the world coordinate system.