CLAUDE: CuasRender - disparity defined for ALL tiles (conditionDisparityCuas)

Per Andrey: the sky has nothing to match but is the BACKGROUND FOR DRONES -
it must render (at infinity), NaN acceptable only outside the image.

Root of the NaN tiles in -CUAS-RT-RENDER: use_lma_dsi=true selected the LMA
DSI slice, which is NaN wherever the LMA did not fit (the whole sky) ->
tiles dropped from the task list. The plain slice has no NaN but carries
garbage (crazy < -1 tiles in the sky, negatives near the sign post).

Fix: NEW static QuadCLT-free conditionDisparityCuas() (the legacy
conditionInitialDS takes a QuadCLT instance - out per the RT rules):
plain slice 0, NaN -> 0.0 (infinity), negatives -> 0.0. testRenderSequence
now uses it unconditionally (not gated by use_lma_dsi - that gate is for
the pose measurement, not rendering).

Verified: mvn -DskipTests clean package OK.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/main/java/com/elphel/imagej/cuas/rt/CuasRender.java

@@ -66,6 +66,27 @@ import ij.ImageStack;
 public class CuasRender {
 	public static final double [] ZERO3 = {0.0, 0.0, 0.0};
 
+	/**
+	 * CUAS disparity conditioning for RENDERING (static, QuadCLT-free - the legacy
+	 * conditionInitialDS takes a QuadCLT instance and is out per the RT rules).
+	 * Requirements (Andrey 2026-07-05): disparity must be DEFINED FOR ALL TILES - the
+	 * sky has nothing to match but is the background for drones, so it renders at
+	 * infinity (disparity 0); NaN is acceptable only outside the image. The raw plain
+	 * DSI slice has no NaN but carries garbage (crazy tiles < -1 in the sky, negatives
+	 * near high-contrast posts) - all non-physical: clamp to >= 0.
+	 * @param disparity plain disparity (slice 0 of -INTER-INTRA-LMA), NOT the LMA slice
+	 *                  (which is NaN wherever the LMA did not fit - the whole sky)
+	 * @return conditioned copy: NaN -> 0.0 (infinity), negatives -> 0.0
+	 */
+	public static double [] conditionDisparityCuas(final double [] disparity) {
+		final double [] cond = new double [disparity.length];
+		for (int i = 0; i < disparity.length; i++) {
+			final double d = disparity[i];
+			cond[i] = (Double.isNaN(d) || (d < 0.0)) ? 0.0 : d;
+		}
+		return cond;
+	}
+
 	/**
 	 * Render ONE scene (already ingested to the GPU by CuasConditioning.conditionSceneToGpu)
 	 * on the virtual-camera uniform grid at the given (borrowed or fitted) pose.
@@ -221,12 +242,14 @@ public class CuasRender {
 			final QuadCLT []    quadCLTs,
 			final int           debugLevel) {
 		final int margin = clt_parameters.imp.margin;
-		final boolean use_lma_dsi = clt_parameters.imp.use_lma_dsi;
 		final boolean is_aux = center_CLT.isAux();
 		final double [][] center_dsi = center_CLT.dsi;
-		final double [] disparity =     center_dsi[is_aux ? TwoQuadCLT.DSI_DISPARITY_AUX     : TwoQuadCLT.DSI_DISPARITY_MAIN];
-		final double [] disparity_lma = center_dsi[is_aux ? TwoQuadCLT.DSI_DISPARITY_AUX_LMA : TwoQuadCLT.DSI_DISPARITY_MAIN_LMA];
-		final double [] center_disparity = (use_lma_dsi && (disparity_lma != null)) ? disparity_lma : disparity;
+		// RENDERING disparity: the PLAIN slice conditioned to be defined for ALL tiles
+		// (sky = infinity/0). Deliberately NOT gated by use_lma_dsi: the LMA slice is NaN
+		// wherever the LMA did not fit (the whole sky) and would drop those tiles from the
+		// render. By Claude on 07/05/2026, per Andrey.
+		final double [] center_disparity = conditionDisparityCuas(
+				center_dsi[is_aux ? TwoQuadCLT.DSI_DISPARITY_AUX : TwoQuadCLT.DSI_DISPARITY_MAIN]);
 		final ErsCorrection ers_center = center_CLT.getErsCorrection();
 		final ImageDtt image_dtt = new ImageDtt(
 				center_CLT.getNumSensors(),