Create forward prjection structure for twin cluster.

Add functions to create forward projection structure for twin cluster.

Signed-off-by: Zheheng Liu zheheng.liu@esrf.fr

Closes #2 (closed)

4_grains/gtGrainAddNoiseVariances.m

+function gr = gtGrainAddNoiseVariances(gr, phase_id, p, detinds)
+    if (~exist('phase_id', 'var')) || isempty(phase_id)
+        phase_id = 1;
+    end
+    if (~exist('detinds', 'var')) || isempty(detinds)
+        detinds = 1;
+    end
+    if (~exist('p', 'var')) || isempty(p)
+        p = gtLoadParameters;
+    end
+    if isnumeric(gr)
+        gr = gtLoadGrain(phase_id, gr);
+    end
+    if isfield(p.rec.grains.options, 'detector_weights') ...
+            && isfield(p.rec.grains.options.detector_weights, 'add_weights_in_6D_algo')
+        flag_add_weights = p.rec.grains.options.detector_weights.add_weights_in_6D_algo;
+        if (flag_add_weights > 0)
+            if flag_add_weights == 1 ...
+                    && isfield(gr.proj(detinds).bl(1), 'nvar') ...
+                    && ~isempty(gr.proj(detinds).bl(1).nvar)
+                return
+            end
+            detwei = GtGrainCalcBlobNoiseVars(gr, phase_id, p, detinds);
+            gr = detwei.grain;
+        end
+    end
+end
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