Skip to content

Commit

Permalink
Added: Right(), Bottom(), SetTopLeft()
Browse files Browse the repository at this point in the history
  • Loading branch information
@setanarut
setanarut committed Dec 26, 2024
1 parent b116164 commit 69a987b
Showing 1 changed file with 59 additions and 35 deletions.
94 changes: 59 additions & 35 deletions camera.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -26,7 +26,10 @@ const (
//
// Use the `Camera.LookAt()` to align the center of the camera to the target.
type Camera struct {

// Top-left X position of camera
TopLeftX float64
// Top-left Y position of camera
TopLeftY float64
// ZoomFactor is the camera zoom (scaling) factor. Default is 1.
ZoomFactor float64

Expand All @@ -46,11 +49,11 @@ type Camera struct {
ShakeOptions *ShakeOptions

// private
drawOptions *ebiten.DrawImageOptions
drawOptionsCM *colorm.DrawImageOptions
angle, actualAngle, tickSpeed, tick, trauma, w, h, zoomFactorShake float64
tempTargetX, centerOffsetX, topLeftX, traumaOffsetX, currentVelocityX float64
tempTargetY, centerOffsetY, topLeftY, traumaOffsetY, currentVelocityY float64
drawOptions *ebiten.DrawImageOptions
drawOptionsCM *colorm.DrawImageOptions
angle, actualAngle, tickSpeed, tick, trauma, w, h, zoomFactorShake float64
tempTargetX, centerOffsetX, traumaOffsetX, currentVelocityX float64
tempTargetY, centerOffsetY, traumaOffsetY, currentVelocityY float64
}

// NewCamera returns new Camera
Expand Down Expand Up @@ -174,48 +177,50 @@ func (cam *Camera) smoothDampY(targetY float64) float64 {
}

// LookAt aligns the midpoint of the camera viewport to the target.
//
// Camera motion smoothing is only applied with this method.
// Use this function only once in Update() and change only the (targetX, targetY)
func (cam *Camera) LookAt(targetX, targetY float64) {
switch cam.SmoothType {
case SmoothDamp:
if !cam.XAxisSmoothingDisabled && !cam.YAxisSmoothingDisabled {
cam.tempTargetX = cam.smoothDampX(targetX)
cam.tempTargetY = cam.smoothDampY(targetY)
cam.topLeftX = cam.tempTargetX
cam.topLeftY = cam.tempTargetY
cam.TopLeftX = cam.tempTargetX
cam.TopLeftY = cam.tempTargetY
} else if !cam.XAxisSmoothingDisabled && cam.YAxisSmoothingDisabled {
cam.tempTargetX = cam.smoothDampX(targetX)
cam.topLeftX = cam.tempTargetX
cam.topLeftY = targetY
cam.TopLeftX = cam.tempTargetX
cam.TopLeftY = targetY
} else if cam.XAxisSmoothingDisabled && !cam.YAxisSmoothingDisabled {
cam.tempTargetY = cam.smoothDampY(targetY)
cam.topLeftY = cam.tempTargetY
cam.topLeftX = targetX
cam.TopLeftY = cam.tempTargetY
cam.TopLeftX = targetX
} else {
cam.topLeftX = targetX
cam.topLeftY = targetY
cam.TopLeftX = targetX
cam.TopLeftY = targetY
}
case Lerp:
if !cam.XAxisSmoothingDisabled && !cam.YAxisSmoothingDisabled {
cam.tempTargetX = lerp(cam.tempTargetX, targetX, cam.SmoothOptions.LerpSpeedX)
cam.tempTargetY = lerp(cam.tempTargetY, targetY, cam.SmoothOptions.LerpSpeedY)
cam.topLeftX = cam.tempTargetX
cam.topLeftY = cam.tempTargetY
cam.TopLeftX = cam.tempTargetX
cam.TopLeftY = cam.tempTargetY
} else if !cam.XAxisSmoothingDisabled && cam.YAxisSmoothingDisabled {
cam.tempTargetX = lerp(cam.tempTargetX, targetX, cam.SmoothOptions.LerpSpeedX)
cam.topLeftX = cam.tempTargetX
cam.topLeftY = targetY
cam.TopLeftX = cam.tempTargetX
cam.TopLeftY = targetY
} else if cam.XAxisSmoothingDisabled && !cam.YAxisSmoothingDisabled {
cam.tempTargetY = lerp(cam.tempTargetY, targetY, cam.SmoothOptions.LerpSpeedY)
cam.topLeftY = cam.tempTargetY
cam.topLeftX = targetX
cam.TopLeftY = cam.tempTargetY
cam.TopLeftX = targetX
} else {
cam.topLeftX = targetX
cam.topLeftY = targetY
cam.TopLeftX = targetX
cam.TopLeftY = targetY
}
default:
cam.topLeftX = targetX
cam.topLeftY = targetY
cam.TopLeftX = targetX
cam.TopLeftY = targetY
}
if cam.ShakeEnabled {
if cam.trauma > 0 {
Expand Down Expand Up @@ -243,8 +248,8 @@ func (cam *Camera) LookAt(targetX, targetY float64) {

// offset
cam.actualAngle += cam.angle
cam.topLeftX += cam.traumaOffsetX
cam.topLeftY += cam.traumaOffsetY
cam.TopLeftX += cam.traumaOffsetX
cam.TopLeftY += cam.traumaOffsetY

// tick
cam.tick += cam.tickSpeed
Expand All @@ -256,8 +261,8 @@ func (cam *Camera) LookAt(targetX, targetY float64) {
cam.zoomFactorShake = cam.ZoomFactor
cam.actualAngle = cam.angle

cam.topLeftX += cam.centerOffsetX
cam.topLeftY += cam.centerOffsetY
cam.TopLeftX += cam.centerOffsetX
cam.TopLeftY += cam.centerOffsetY

cam.trauma = 0
cam.traumaOffsetX, cam.traumaOffsetY = 0, 0
Expand All @@ -271,14 +276,33 @@ func (cam *Camera) AddTrauma(factor float64) {
}
}

// TopLeft returns top left position of the camera in world-space
// TopLeft returns top-left position of the camera in world-space
func (cam *Camera) TopLeft() (X float64, Y float64) {
return cam.topLeftX, cam.topLeftY
return cam.TopLeftX, cam.TopLeftY
}

// Right returns the right edge position of the camera in world-space.
func (cam *Camera) Right() float64 {
return cam.TopLeftX + cam.w
}

// Bottom returns the bottom edge position of the camera in world-space.
func (cam *Camera) Bottom() float64 {
return cam.TopLeftY + cam.h
}

// SetTopLeft sets top-left position of the camera in world-space.
//
// Unlike the LookAt() method, the position is set directly without any smoothing.
//
// Useful for static cameras.
func (cam *Camera) SetTopLeft(x, y float64) {
cam.TopLeftX, cam.TopLeftY = x, y
}

// Center returns center point of the camera in world-space
func (cam *Camera) Center() (X float64, Y float64) {
return cam.topLeftX - cam.centerOffsetX, cam.topLeftY - cam.centerOffsetY
return cam.TopLeftX - cam.centerOffsetX, cam.TopLeftY - cam.centerOffsetY
}

// ActualAngle returns camera rotation angle (including the angle of trauma shaking.).
Expand Down Expand Up @@ -310,7 +334,7 @@ func (cam *Camera) Height() float64 {
return cam.h
}

// SetSize sets camera rectangle size
// SetSize sets camera rectangle size from center.
func (cam *Camera) SetSize(w, h float64) {
cx, cy := cam.Center()
cam.w, cam.h = w, h
Expand Down Expand Up @@ -351,8 +375,8 @@ func (cam *Camera) String() string {

return fmt.Sprintf(
cameraStats,
cam.topLeftX-cam.centerOffsetX,
cam.topLeftY-cam.centerOffsetY,
cam.TopLeftX-cam.centerOffsetX,
cam.TopLeftY-cam.centerOffsetY,
cam.actualAngle,
cam.zoomFactorShake,
cam.ShakeEnabled,
Expand Down Expand Up @@ -389,7 +413,7 @@ func (cam *Camera) ApplyCameraTransformToPoint(x, y float64) (float64, float64)

// ApplyCameraTransform applies geometric transformation to given geoM
func (cam *Camera) ApplyCameraTransform(geoM *ebiten.GeoM) {
geoM.Translate(-cam.topLeftX, -cam.topLeftY) // camera movement
geoM.Translate(-cam.TopLeftX, -cam.TopLeftY) // camera movement
geoM.Translate(cam.centerOffsetX, cam.centerOffsetY) // rotate and scale from center.
geoM.Rotate(cam.actualAngle) // rotate
geoM.Scale(cam.zoomFactorShake, cam.zoomFactorShake) // apply zoom factor
Expand Down

0 comments on commit 69a987b

Please sign in to comment.