detectSpatialScaleGesture
Gesture detector that detects a spatial scale and calls onScale for each event with a 3D scale value, see SpatialScaleValue. Usually, you can apply this gesture detector to a composable view, and apply the 3D scale value to a 2D view, through Modifier.scale or Modifier.graphicsLayer, or to a 3D model Entity through TransformComponent. Entity is not interactable by default. To make an Entity interactable, you should both add an InteractableComponent and a CollisionComponent to this entity. The targetedToEntity parameter determines whether the gesture is bound to entities. Null means that this gesture can detect scale events that happen on a 2D view or 3D model within this view. See TargetEntity for more details.
Parameters
Android context. You can get context by LocalContext.current.
The entity that this gesture is bound to.
The callback that is called when the scale gesture starts. It provides the current scale context with SpatialScaleValue.scaleValue set to 1f.
The callback that is called when the scale gesture ends. It provides the last valid matched scale context with SpatialScaleValue.scaleValue set to 1f.
The callback that is called when the scale gesture is canceled. It provides the last valid matched scale context with SpatialScaleValue.scaleValue set to 1f.
The callback that is called for each scale event.
Samples
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.size
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableFloatStateOf
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.scale
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.input.pointer.pointerInput
import androidx.compose.ui.platform.LocalContext
import androidx.compose.ui.unit.dp
import com.pico.spatial.core.ecs.CollisionComponent
import com.pico.spatial.core.ecs.Entity
import com.pico.spatial.core.ecs.InteractableComponent
import com.pico.spatial.core.ecs.TransformComponent
import com.pico.spatial.core.ecs.resource.PhysicsMaterialResource
import com.pico.spatial.core.ecs.resource.ShapeResource
import com.pico.spatial.core.math.Vector3
import com.pico.spatial.ui.foundation.content.SpatialView
import com.pico.spatial.ui.foundation.effect3d.scale3D
import com.pico.spatial.ui.foundation.geometry.NormalizedPoint3D
import com.pico.spatial.ui.foundation.gesture.TargetEntity
import com.pico.spatial.ui.foundation.gesture.detectSpatialScaleGesture
fun main() {
//sampleStart
Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
val context = LocalContext.current
var scale by remember { mutableFloatStateOf(1f) }
var pivot by remember { mutableStateOf(NormalizedPoint3D.Center) }
Box(
modifier =
Modifier.size(250.dp)
.scale(scale)
.background(Color.Red)
.pointerInput(Unit) {
detectSpatialScaleGesture(context) {
scale *= it.scaleValue
pivot = it.centroid
}
}
.scale3D(scale = scale, pivot = pivot)
)
}
//sampleEnd
}import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.size
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableFloatStateOf
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.scale
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.input.pointer.pointerInput
import androidx.compose.ui.platform.LocalContext
import androidx.compose.ui.unit.dp
import com.pico.spatial.core.ecs.CollisionComponent
import com.pico.spatial.core.ecs.Entity
import com.pico.spatial.core.ecs.InteractableComponent
import com.pico.spatial.core.ecs.TransformComponent
import com.pico.spatial.core.ecs.resource.PhysicsMaterialResource
import com.pico.spatial.core.ecs.resource.ShapeResource
import com.pico.spatial.core.math.Vector3
import com.pico.spatial.ui.foundation.content.SpatialView
import com.pico.spatial.ui.foundation.effect3d.scale3D
import com.pico.spatial.ui.foundation.geometry.NormalizedPoint3D
import com.pico.spatial.ui.foundation.gesture.TargetEntity
import com.pico.spatial.ui.foundation.gesture.detectSpatialScaleGesture
fun main() {
//sampleStart
val context = LocalContext.current
var scale by remember { mutableFloatStateOf(1f) }
SpatialView(
modifier =
Modifier.fillMaxSize().pointerInput(Unit) {
detectSpatialScaleGesture(
context = context,
targetedToEntity = TargetEntity.any(),
) {
scale *= it.scaleValue
}
},
initial = { content, _ ->
val entity = Entity()
// Entity is not interactable by default. To make an entity interactable, you should
// both
// add a
// [InputTargetComponent] and a [CollisionComponent].
entity.components.set(InteractableComponent())
entity.components.set(
CollisionComponent(
collisionShape = listOf(ShapeResource.createSphere(radius = 0.3f)),
physicsMaterial = PhysicsMaterialResource(),
)
)
content.addEntity(entity)
},
update = { content, _ ->
content.entities
.first()
.components[TransformComponent::class.java]
?.setScaleVector(Vector3(scale, scale, scale))
},
)
//sampleEnd
}