wip leg animator

src/main/java/de/bixilon/minosoft/gui/rendering/entities/model/biped/HumanModel.kt

@@ -15,14 +15,21 @@ package de.bixilon.minosoft.gui.rendering.entities.model.biped
 
 import de.bixilon.minosoft.gui.rendering.entities.feature.SkeletalFeature
 import de.bixilon.minosoft.gui.rendering.entities.model.biped.animator.HeadPosition
+import de.bixilon.minosoft.gui.rendering.entities.model.biped.animator.LegAnimator
 import de.bixilon.minosoft.gui.rendering.entities.renderer.EntityRenderer
 import de.bixilon.minosoft.gui.rendering.skeletal.baked.BakedSkeletalModel
 
 abstract class HumanModel<R : EntityRenderer<*>>(renderer: R, model: BakedSkeletalModel) : SkeletalFeature(renderer, model) {
     val head = instance.transform.children["head"]?.let { HeadPosition(this, it) }
+    val leg = LegAnimator(this, instance.transform.children["left_leg"]!!, instance.transform.children["right_leg"]!!)
 
     override fun updatePosition() {
         super.updatePosition()
         head?.update()
     }
+
+    override fun update(millis: Long, delta: Float) {
+        super.update(millis, delta)
+        leg.update(delta)
+    }
 }

src/main/java/de/bixilon/minosoft/gui/rendering/entities/model/biped/animator/LegAnimator.kt

@@ -0,0 +1,87 @@
+/*
+ * Minosoft
+ * Copyright (C) 2020-2023 Moritz Zwerger
+ *
+ * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This software is not affiliated with Mojang AB, the original developer of Minecraft.
+ */
+
+package de.bixilon.minosoft.gui.rendering.entities.model.biped.animator
+
+import de.bixilon.kotlinglm.vec3.Vec3
+import de.bixilon.kotlinglm.vec3.Vec3d
+import de.bixilon.kotlinglm.vec3.swizzle.xz
+import de.bixilon.kutil.math.MathConstants.PIf
+import de.bixilon.kutil.math.interpolation.FloatInterpolation
+import de.bixilon.kutil.math.interpolation.FloatInterpolation.interpolateLinear
+import de.bixilon.minosoft.gui.rendering.entities.model.biped.HumanModel
+import de.bixilon.minosoft.gui.rendering.skeletal.instance.TransformInstance
+import de.bixilon.minosoft.gui.rendering.util.mat.mat4.Mat4Util.rotateDegreesAssign
+import de.bixilon.minosoft.gui.rendering.util.vec.vec3.Vec3dUtil.EMPTY
+import de.bixilon.minosoft.protocol.protocol.ProtocolDefinition
+import de.bixilon.minosoft.util.interpolate.Interpolator
+import kotlin.math.sin
+
+class LegAnimator(
+    val model: HumanModel<*>,
+    val left: TransformInstance,
+    val right: TransformInstance,
+) {
+    private val velocity = Interpolator(0.0f, FloatInterpolation::interpolateLinear)
+    private var position0 = Vec3d.EMPTY
+    private var maxAngle = 0.0f
+    private var progress = 0.0f
+    private var strength = 1.0f
+
+    private fun updateVelocity(delta: Float) {
+        if (this.velocity.delta >= 1.0f) {
+            val position = model.renderer.entity.physics.position
+            val deltaPosition = position.xz - position0.xz
+            this.position0 = position
+            var value = deltaPosition.length2().toFloat() * (VELOCITY_TIME / (ProtocolDefinition.TICK_TIMEf / 1000.0f)) / 5.0f
+
+            if (value > 1.0f) value = 1.0f
+            if (value < 0.1f && value > 0.001f) value = 0.1f
+            value *= value
+            this.velocity.push(value)
+        }
+        this.velocity.add(delta, VELOCITY_TIME)
+    }
+
+    private fun updateAngle(delta: Float) {
+        this.maxAngle = interpolateLinear(velocity.value * VELOCITY_ANGLE, 0.0f, MAX_ANGLE)
+        this.progress += strength * delta * 5.0f * velocity.value
+        this.progress %= 2.0f
+    }
+
+    fun update(delta: Float) {
+        updateVelocity(delta)
+        updateAngle(delta)
+        apply()
+    }
+
+    private fun apply() {
+        if (this.maxAngle == 0.0f) return
+        val progress = sin((progress - 1.0f) * PIf) * this.maxAngle
+
+        left.value
+            .translateAssign(left.pivot)
+            .rotateDegreesAssign(Vec3(progress * -1.0f, 0.0f, 0.0f))
+            .translateAssign(left.nPivot)
+        right.value
+            .translateAssign(left.pivot)
+            .rotateDegreesAssign(Vec3(progress, 0.0f, 0.0f))
+            .translateAssign(left.nPivot)
+    }
+
+    private companion object {
+        const val MAX_ANGLE = 45.0f
+        const val VELOCITY_TIME = 0.2f
+        const val VELOCITY_ANGLE = 5.0f
+    }
+}