From 459b3249a43ccf2b153ee6519bad8d2e12abc963 Mon Sep 17 00:00:00 2001
From: tkrmagid <tkrmagid@git.tkrmagid.kr>
Date: Fri, 15 May 2026 20:21:19 +0900
Subject: [PATCH] fix(render): anchor video to clicked block's bottom-left,
 EAST/WEST flush
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Three fixes for v0.4.1:

1. Video stick item rendered as missing-texture because 26.1.2 requires the
   new client_item descriptor at assets/<mod>/items/<name>.json. Add it; the
   existing models/item/video_stick.json is kept as the underlying model.

2. Quad placement now anchors the local (0,0) corner at the bottom-left of
   the wall face the player clicked, so the clicked block is the BL and the
   video grows up & right. Previously it was centered on the anchor.

3. EAST/WEST face rotations were swapped, which placed the quad on the far
   side of the air block (~1 block away from the wall) instead of flush.
   Derived the correct rotations from first principles:
     EAST = Axis.YP +90°  (local +Z → world +X, +X → -Z = north)
     WEST = Axis.YP -90°  (local +Z → world -X, +X → +Z = south)
   NORTH/SOUTH/UP/DOWN math re-verified — those were already correct.
---
 gradle.properties                             |  2 +-
 .../client/render/VideoAnchorRenderer.java    | 28 ++++++++++++-------
 .../video_player/items/video_stick.json       |  6 ++++
 3 files changed, 25 insertions(+), 11 deletions(-)
 create mode 100644 src/main/resources/assets/video_player/items/video_stick.json

diff --git a/gradle.properties b/gradle.properties
index 74749fc..2761ae0 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -5,7 +5,7 @@ org.gradle.configuration-cache=false
 
 # Mod
 mod_id=video_player
-mod_version=0.4.0
+mod_version=0.4.1
 maven_group=com.ejclaw.videoplayer
 archives_base_name=video_player
 
diff --git a/src/main/java/com/ejclaw/videoplayer/client/render/VideoAnchorRenderer.java b/src/main/java/com/ejclaw/videoplayer/client/render/VideoAnchorRenderer.java
index ab075ea..dbb582b 100644
--- a/src/main/java/com/ejclaw/videoplayer/client/render/VideoAnchorRenderer.java
+++ b/src/main/java/com/ejclaw/videoplayer/client/render/VideoAnchorRenderer.java
@@ -67,9 +67,11 @@ public class VideoAnchorRenderer implements BlockEntityRenderer<VideoAnchorBlock
         pose.translate(0.5F, 0.5F, 0.5F);
         // 2) Rotate local +Z to align with the wall's outward normal.
         applyFaceRotation(pose, f);
-        // 3) Center the quad on origin (local XY) and push it back 0.5 - ε so it lands on the
-        //    wall surface (the boundary face between the anchor's air block and the wall block).
-        pose.translate(-w / 2.0F, -h / 2.0F, -0.5F + SURFACE_EPSILON);
+        // 3) Place the quad's local origin (0,0) at the bottom-left corner of the anchor block's
+        //    wall face, so the clicked block becomes the lower-left and the video grows up & right.
+        //    Push it onto the wall surface (-0.5 along local +Z, the outward normal) plus a tiny
+        //    epsilon outward so the quad doesn't z-fight with the wall.
+        pose.translate(-0.5F, -0.5F, -0.5F + SURFACE_EPSILON);
 
         final Matrix4f mat = new Matrix4f(pose.last().pose());
         RenderType rt = RenderTypes.entityCutout(tex);
@@ -89,15 +91,21 @@ public class VideoAnchorRenderer implements BlockEntityRenderer<VideoAnchorBlock
         pose.popPose();
     }
 
-    /** Rotate so local +Z (the quad's outward normal in its base orientation) becomes world {@code f}. */
+    /**
+     * Rotate so local +Z (the quad's outward normal in its base orientation) becomes world {@code f},
+     * with local +X mapped to the natural "right" direction the player sees when looking at the face.
+     * Derivation: for each face {@code f}, pick the rotation that maps local +Z → f, +Y → world up
+     * (or a sensible substitute for top/bottom), so the quad lies flush against the wall, oriented
+     * the way the player intuits.
+     */
     private static void applyFaceRotation(PoseStack pose, Direction f) {
         switch (f) {
-            case SOUTH -> { /* identity: local +Z already faces world +Z (south) */ }
-            case NORTH -> pose.mulPose(Axis.YP.rotationDegrees(180F));
-            case EAST  -> pose.mulPose(Axis.YP.rotationDegrees(-90F));
-            case WEST  -> pose.mulPose(Axis.YP.rotationDegrees(90F));
-            case UP    -> pose.mulPose(Axis.XP.rotationDegrees(-90F));
-            case DOWN  -> pose.mulPose(Axis.XP.rotationDegrees(90F));
+            case SOUTH -> { /* identity: local +Z = world +Z (south). +X = east, +Y = up. */ }
+            case NORTH -> pose.mulPose(Axis.YP.rotationDegrees(180F));  // +Z → -Z, +X → -X (west)
+            case EAST  -> pose.mulPose(Axis.YP.rotationDegrees(90F));   // +Z → +X, +X → -Z (north)
+            case WEST  -> pose.mulPose(Axis.YP.rotationDegrees(-90F));  // +Z → -X, +X → +Z (south)
+            case UP    -> pose.mulPose(Axis.XP.rotationDegrees(-90F));  // +Z → +Y, +Y → -Z (north)
+            case DOWN  -> pose.mulPose(Axis.XP.rotationDegrees(90F));   // +Z → -Y, +Y → +Z (south)
         }
     }
 
diff --git a/src/main/resources/assets/video_player/items/video_stick.json b/src/main/resources/assets/video_player/items/video_stick.json
new file mode 100644
index 0000000..c5c4ad9
--- /dev/null
+++ b/src/main/resources/assets/video_player/items/video_stick.json
@@ -0,0 +1,6 @@
+{
+  "model": {
+    "type": "minecraft:model",
+    "model": "video_player:item/video_stick"
+  }
+}