Expand link preview to cubic snapshot

src/main/java/net/dnorberg/rivencraft/client/preview/PonderDestinationPreviewRenderer.java

@@ -43,7 +43,12 @@ public final class PonderDestinationPreviewRenderer implements DestinationPrevie
     public PonderDestinationPreviewRenderer() {
         Minecraft minecraft = Minecraft.getInstance();
         previewLevel = new PonderLevel(BlockPos.ZERO, minecraft.level);
-        snapshotSelection = SelectionImpl.of(new BoundingBox(0, 0, 0, 8, 63, 8));
+        snapshotSelection = SelectionImpl.of(new BoundingBox(
+                0, 0, 0,
+                LinkPreviewPayload.SNAPSHOT_SIZE - 1,
+                LinkPreviewPayload.SNAPSHOT_SIZE - 1,
+                LinkPreviewPayload.SNAPSHOT_SIZE - 1
+        ));
         // Keep the target-centered 9×7×9 camera framing below, but give Ponder
         // the entire snapshot so terrain above and below that window is still
         // part of the rotating scene.
@@ -109,7 +114,9 @@ public final class PonderDestinationPreviewRenderer implements DestinationPrevie
         poseStack.mulPose(Axis.YP.rotationDegrees((ticks + partialTick) * 0.6F));
         UIRenderHelper.flipForGuiRender(poseStack);
         poseStack.scale(7.0F, 7.0F, 7.0F);
-        poseStack.translate(-4.5F, -31.5F, -4.5F);
+        // The target moves from (4, 32, 4) to (9, 9, 9) in the cubic
+        // snapshot, so retain its existing camera position relative to it.
+        poseStack.translate(-9.5F, -8.5F, -9.5F);
 
         SuperRenderTypeBuffer buffer = DefaultSuperRenderTypeBuffer.getInstance();
         section.renderFirst(previewLevel, buffer, graphics, partialTick);

src/main/java/net/dnorberg/rivencraft/network/LinkPreviewPayload.java

@@ -12,8 +12,10 @@ import net.minecraft.world.level.block.Block;
 import net.minecraft.world.level.block.state.BlockState;
 
 public record LinkPreviewPayload(int skyColor, List<SnapshotBlock> blocks) implements CustomPacketPayload {
-    /** A square footprint keeps every side visible during an orbit, with a vertical snapshot cache. */
-    private static final int MAX_BLOCKS = 9 * 64 * 9;
+    /** Each axis of the destination volume captured for the book preview. */
+    public static final int SNAPSHOT_SIZE = 18;
+    /** A square footprint keeps every side visible during an orbit. */
+    private static final int MAX_BLOCKS = SNAPSHOT_SIZE * SNAPSHOT_SIZE * SNAPSHOT_SIZE;
     public static final Type<LinkPreviewPayload> TYPE = new Type<>(
             ResourceLocation.fromNamespaceAndPath(Rivencraft.MOD_ID, "link_preview")
     );

src/main/java/net/dnorberg/rivencraft/network/ModNetworking.java

@@ -114,12 +114,17 @@ public final class ModNetworking {
 
         BlockPos origin = target.location().pos();
         List<LinkPreviewPayload.SnapshotBlock> blocks = new ArrayList<>();
-        // The square footprint survives every angle of the orbit. Retain a
-        // 64-block vertical slice, while the renderer shows its 7-block window.
-        for (BlockPos pos : BlockPos.betweenClosed(origin.offset(-4, -32, -4), origin.offset(4, 31, 4))) {
+        // The cubic footprint survives every angle of the orbit. The target is
+        // kept at the preview camera's current center point.
+        int negativeRadius = LinkPreviewPayload.SNAPSHOT_SIZE / 2;
+        int positiveRadius = negativeRadius - 1;
+        for (BlockPos pos : BlockPos.betweenClosed(
+                origin.offset(-negativeRadius, -negativeRadius, -negativeRadius),
+                origin.offset(positiveRadius, positiveRadius, positiveRadius))) {
             var state = level.getBlockState(pos);
             if (!state.isAir()) {
-                blocks.add(new LinkPreviewPayload.SnapshotBlock(pos.subtract(origin).offset(4, 32, 4), state));
+                blocks.add(new LinkPreviewPayload.SnapshotBlock(
+                        pos.subtract(origin).offset(negativeRadius, negativeRadius, negativeRadius), state));
             }
         }
         int skyColor = level.getBiome(origin).value().getSkyColor();