Pure 2D camera settings for world-space drawing.
Cameras are pure values passed to Draw.with_camera!; they hold no host
resource.
camera = Camera.centered(model.player, Math.vec2(800, 600))
frame.with_camera!(camera, |world| {
world.circle!({ center: model.player, radius: 12, style: Draw.filled(Color.white) })
Ok({})
})?Constructors are total. Non-finite positions and rotations become 0;
zero or non-finite zoom becomes fallback_zoom, preserving a negative sign
for mirrored cameras. Other finite values are unchanged.
The zoom substituted for a zoom that cannot be used, meaning zero (which has no inverse) or a non-finite one (which has no meaning).
Deliberately tiny rather than 1: a camera that had to be rescued
collapses the world to a dot at its offset, which reads on screen as the
mistake it is, instead of quietly looking plausible.
default : Camera2DIdentity camera: no offset or rotation, with unit zoom.
new : Settings -> Camera2DConstruct a camera from explicit settings.
Total: non-finite target, offset, and rotation components become
0, and a zoom of zero or one that is not finite becomes
fallback_zoom with the same sign. Every usable setting is kept exactly.
centered : Vec2, Vec2 -> Camera2DPlace target at the center of a screen with unit zoom.
Total: a non-finite component of either vector becomes 0.
A common player-follow camera with a configurable zoom.
Total: a non-finite target or screen component becomes 0, and a
zoom of zero or one that is not finite becomes fallback_zoom with the
same sign.
Target, screen offset, clockwise rotation in degrees, and zoom factor.
Camera.Camera2D :: # (opaque)Immutable camera value accepted by drawing and coordinate transforms.
Draw.Camera2D names this same type.
Its representation is opaque so non-finite transform fields, or a zero zoom that has no inverse, cannot bypass the sanitizing every constructor applies. The module header states what is rewritten and what is left alone.
target : Camera2D -> Vec2World-space point placed at the camera offset.
offset : Camera2D -> Vec2Logical screen-space offset of the target.
Clockwise camera rotation in degrees.
Non-zero camera zoom factor. Negative values intentionally mirror axes.
with_target : Camera2D, Vec2 -> Camera2DReturn a copy focused on new_target.
Total: a component of new_target that is not finite becomes 0,
and every finite coordinate is kept exactly.
with_offset : Camera2D, Vec2 -> Camera2DReturn a copy with new_offset as its logical screen-space offset.
Total: a component of new_offset that is not finite becomes 0,
and every finite coordinate is kept exactly.
with_rotation : Camera2D, F32 -> Camera2DReturn a copy rotated new_rotation degrees clockwise.
Total: a new_rotation that is not finite becomes 0. Any finite
angle is kept exactly, including one outside 0 to 360 -- degrees wrap
through the sine and cosine, so there is no range to clamp to.
Return a copy zoomed by new_zoom.
Total: a new_zoom of zero has no inverse and one that is not finite
has no meaning, so either becomes fallback_zoom with the same sign.
Every other zoom is kept exactly, so a negative zoom still mirrors
both axes.
clamp_zoom : Camera2D, { min : F32, max : F32 } -> Camera2DClamp zoom to inclusive limits.
Total: limits that produce a zero or non-finite zoom fall back to
fallback_zoom, exactly as with_zoom does.
world_to_screen : Camera2D, Vec2 -> Vec2Convert a world-space point to logical screen coordinates.
Rotation uses degrees, matching raylib and Draw.with_camera!.
screen_to_world : Camera2D, Vec2 -> Vec2Convert logical screen coordinates back to world space. Every Camera2D is invertible because no constructor lets a zoom of zero through.
viewport : Camera2D, Vec2 -> RectWorld-space axis-aligned bounds visible through this camera. This handles non-centered offsets, rotation, and mirrored (negative) zoom.