Improving support generation in dual extrusion scenarios

issue: MatterHackers/MCCentral#5275
Dual extruder support fail

MatterControlLib/DesignTools/SupportGenerator.cs

@@ -354,11 +354,9 @@ namespace MatterHackers.MatterControl.DesignTools
 					if (!nextPlaneIsBottom // if the next plane is a top, we don't have any space from the bed to the part to put support
 						|| planes[1].z > minimumSupportHeight) // if the next plane is a bottom and is not far enough away, there is no space to put any support
 					{
-						var firstBottomAboveBed = GetNextBottom(0, planes);
+						var firstBottomAboveBed = GetNextBottom(0, planes, minimumSupportHeight);
-						var firstTopAboveBed = GetNextTop(0, planes);
 
-						if (firstBottomAboveBed >= 0
+						if (firstBottomAboveBed >= 0)
-							&& firstBottomAboveBed < firstTopAboveBed)
 						{
 							AddSupportColumn(supportColumnsToAdd, xPos, yPos, 0, planes[firstBottomAboveBed].z + .01);
 						}
@@ -368,21 +366,26 @@ namespace MatterHackers.MatterControl.DesignTools
 				{
 					int i = 0;
 					double lastTopZ = 0;
-					int lastBottom = i;
+					int lastBottom = -1;
 					var nextPlaneIsBottom = planes.Count > 1 && planes[1].bottom;
 					// if the next plane (the one above the bed) is a bottom, we have a part on the bed and will not generate support
 					if (nextPlaneIsBottom && planes[1].z <= minimumSupportHeight)
 					{
 						// go up to the next top
-						i = GetNextTop(i, planes);
+						i = GetNextTop(i, planes, minimumSupportHeight);
-						lastTopZ = planes[i].z;
+						if (i >= 0)
+						{
+							lastTopZ = planes[i].z;
+						}
 					}
 
-					do
+					while (i != -1
+						&& i != lastBottom
+						&& i < planes.Count)
 					{
 						lastBottom = i;
 						// find all open areas in the list and add support
-						i = GetNextBottom(i, planes);
+						i = GetNextBottom(i, planes, minimumSupportHeight);
 						if (i >= 0)
 						{
 							if (i < planes.Count
@@ -390,15 +393,14 @@ namespace MatterHackers.MatterControl.DesignTools
 							{
 								AddSupportColumn(supportColumnsToAdd, xPos, yPos, lastTopZ, planes[i].z);
 							}
-							i = GetNextTop(i + 1, planes);
+							i = GetNextTop(i + 1, planes, minimumSupportHeight);
-							if (i < planes.Count)
+							if (i >= 0
+								&& i < planes.Count)
 							{
 								lastTopZ = planes[i].z;
 							}
 						}
-					} while (i != -1
+					}
-						&& i != lastBottom 
-						&& i < planes.Count);
 				}
 			}
 
@@ -472,71 +474,70 @@ namespace MatterHackers.MatterControl.DesignTools
 			return detectedPlanes;
 		}
 
-		public static int GetNextBottom(int i, List<(double z, bool bottom)> planes)
+		public static int GetNextBottom(int i, List<(double z, bool bottom)> planes, double skipDist)
 		{
-			// if we are starting this search from a top
+			while (i < planes.Count)
-			if(i < planes.Count // valid i
-				&& !planes[i].bottom // starting on a top
-				&& planes.Count > i + 1 // valid next layer
-				&& planes[i + 1].bottom // next layer is a bottom
-				&& planes[i + 1].z <= planes[i].z) // next layer is <= or current top z
 			{
-				// skip all the bottoms that are the same as our current top
+				// if we are on a bottom
-				while (i < planes.Count
+				if (planes[i].bottom)
-					&& planes.Count > i + 1
-					&& planes[i + 1].bottom)
 				{
+					// move up to the next plane and re-evaluate
 					i++;
 				}
-			}
+				else // we are on a top
-
-			bool foundBottom = false;
-
-			// all the tops
-			while (i < planes.Count
-				&& !planes[i].bottom)
-			{
-				i++;
-				if(i <planes.Count
-					&& planes[i].bottom)
 				{
-					foundBottom = true;
+					// if the next plane is a bottom and more than skipDistanc away
+					if (i + 1 < planes.Count
+						&& planes[i + 1].bottom
+						&& planes[i + 1].z > planes[i].z + skipDist)
+					{
+						// this is the next bottom we are looking for
+						return i + 1;
+					}
+					else // move up to the next plane and re-evaluate
+					{
+						i++;
+					}
 				}
 			}
 
-			// then look for the last bottom before next top
-			while (i < planes.Count
-				&& planes[i].bottom
-				&& planes.Count > i + 1
-				&& planes[i + 1].bottom)
-			{
-				i++;
-				foundBottom = true;
-			}
-
-			if (foundBottom)
-			{
-				return i;
-			}
-
 			return -1;
 		}
 
-		public static int GetNextTop(int i, List<(double z, bool bottom)> planes)
+		public static int GetNextTop(int i, List<(double z, bool bottom)> planes, double skipDist)
 		{
-			if(i < planes.Count
+			if (!planes[i].bottom)
-				&& !planes[i].bottom)
 			{
+				// skip the one we are
 				i++;
 			}
 
-			while (i < planes.Count
+			while (i < planes.Count)
-				&& planes[i].bottom)
 			{
-				i++;
+				// if we are on a bottom
+				if (planes[i].bottom)
+				{
+					// move up to the next plane and re-evaluate
+					i++;
+				}
+				else // we are on a top
+				{
+					// if the next plane is a bottom and more than skipDistanc away
+					if (i + 1 < planes.Count
+						&& planes[i + 1].bottom
+						&& planes[i + 1].z > planes[i].z + skipDist)
+					{
+						// this is the next top we are looking for
+						return i;
+					}
+					else // move up to the next plane and re-evaluate
+					{
+						i++;
+					}
+				}
 			}
 
-			return i;
+			return -1;
 		}
 
 		// function to get all the columns that need support generation

Submodules/agg-sharp

@@ -1 +1 @@
-Subproject commit 14f4fb447f973f2f52fd787e014757ca6d06820e
+Subproject commit afd799f6d27bf549934f764bd307dd5c2b2192d7

Tests/MatterControl.Tests/MatterControl/SupportGeneratorTests.cs

@@ -482,10 +482,10 @@ namespace MatterControl.Tests.MatterControl
 					(10, false), // top at 10 (the top of the box)
 				};
 
-				int bottom = SupportGenerator.GetNextBottom(0, planes);
+				int bottom = SupportGenerator.GetNextBottom(0, planes, 0);
 				Assert.AreEqual(1, bottom); // we get the bottom
 
-				int bottom1 = SupportGenerator.GetNextBottom(1, planes);
+				int bottom1 = SupportGenerator.GetNextBottom(1, planes, 0);
 				Assert.AreEqual(-1, bottom1, "There are no more bottoms so we get back a -1.");
 			}
 
@@ -500,7 +500,7 @@ namespace MatterControl.Tests.MatterControl
 					(20, false) // top at 20 (box b top)
 				};
 
-				int bottom = SupportGenerator.GetNextBottom(0, planes);
+				int bottom = SupportGenerator.GetNextBottom(0, planes, 0);
 				Assert.AreEqual(-1, bottom, "The boxes are sitting on the bed and no support is required");
 			}
 
@@ -515,7 +515,7 @@ namespace MatterControl.Tests.MatterControl
 					(20, false) // top at 20 (box b top)
 				};
 
-				int bottom = SupportGenerator.GetNextBottom(0, planes);
+				int bottom = SupportGenerator.GetNextBottom(0, planes, 0);
 				Assert.AreEqual(-1, bottom, "The boxes are sitting on the bed and no support is required");
 			}
 
@@ -526,11 +526,12 @@ namespace MatterControl.Tests.MatterControl
 					(0, false),
 					(5, true), 
 					(10, false),
-					(20, false)
+					(20, false),
+					(25, true)
 				};
 
-				int top = SupportGenerator.GetNextTop(0, planes);
+				int top = SupportGenerator.GetNextTop(0, planes, 0);
-				Assert.AreEqual(2, top);
+				Assert.AreEqual(3, top);
 			}
 		}
 	}