From fa5d41f7e0f8c561eb6c98d7d3d74a2533a1efa4 Mon Sep 17 00:00:00 2001
From: Bixilon <bixilon@bixilon.de>
Date: Sun, 12 Sep 2021 22:24:48 +0200
Subject: [PATCH] only recalculate frustum when position changes (performance)

---
 .../gui/rendering/gui/mesh/GUIMeshCache.kt    |  4 ++--
 .../gui/rendering/input/camera/Camera.kt      | 22 ++++++++++++++++---
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/src/main/java/de/bixilon/minosoft/gui/rendering/gui/mesh/GUIMeshCache.kt b/src/main/java/de/bixilon/minosoft/gui/rendering/gui/mesh/GUIMeshCache.kt
index 09c9c8bf3..1e43f765c 100644
--- a/src/main/java/de/bixilon/minosoft/gui/rendering/gui/mesh/GUIMeshCache.kt
+++ b/src/main/java/de/bixilon/minosoft/gui/rendering/gui/mesh/GUIMeshCache.kt
@@ -24,9 +24,9 @@ import glm_.vec4.Vec4
 
 class GUIMeshCache(
     val matrix: Mat4,
-    initialCahceSize: Int = 1000,
+    initialCacheSize: Int = 1000,
 ) : GUIVertexConsumer {
-    val data: ArrayFloatList = ArrayFloatList(initialCahceSize)
+    val data: ArrayFloatList = ArrayFloatList(initialCacheSize)
 
     override fun addVertex(position: Vec2t<*>, z: Int, texture: AbstractTexture, uv: Vec2, tint: RGBColor) {
         val outPosition = matrix * Vec4(position.x.toFloat(), position.y.toFloat(), 1.0f, 1.0f)
diff --git a/src/main/java/de/bixilon/minosoft/gui/rendering/input/camera/Camera.kt b/src/main/java/de/bixilon/minosoft/gui/rendering/input/camera/Camera.kt
index e071612e7..1d07f4d7e 100644
--- a/src/main/java/de/bixilon/minosoft/gui/rendering/input/camera/Camera.kt
+++ b/src/main/java/de/bixilon/minosoft/gui/rendering/input/camera/Camera.kt
@@ -100,6 +100,11 @@ class Camera(
     var viewProjectionMatrix = projectionMatrix * viewMatrix
         private set
 
+
+    var previousPosition = Vec3d(connection.player.position)
+    var previousRotation = connection.player.rotation.copy()
+    var previousZoom = zoom
+
     private var lastDropPacketSent = -1L
 
     val frustum: Frustum = Frustum(this)
@@ -265,7 +270,14 @@ class Camera(
         connection.fireEvent(FrustumChangeEvent(renderWindow, frustum))
         connection.fireEvent(CameraPositionChangeEvent(renderWindow, connection.player.eyePosition))
 
-        // recalculate sky color for current biome
+        previousPosition = Vec3d(connection.player.position)
+        previousRotation = connection.player.rotation.copy()
+        previousZoom = zoom
+
+        setSkyColor()
+    }
+
+    private fun setSkyColor() {
         renderWindow[SkyRenderer.Companion]?.let { skyRenderer ->
             skyRenderer.baseColor = connection.world.getBiome(connection.player.positionInfo.blockPosition)?.skyColor ?: RenderConstants.DEFAULT_SKY_COLOR
 
@@ -330,8 +342,12 @@ class Camera(
         } else {
             0.0f
         }
-        // ToDo: Only update if changed
-        onPositionChange()
+
+        if (previousPosition != connection.player.position || previousRotation != connection.player.rotation || zoom != previousZoom) {
+            onPositionChange()
+        } else {
+            setSkyColor()
+        }
 
         val eyePosition = connection.player.eyePosition
         val cameraFront = cameraFront