fix integral image

computer-graphics-tools · Mar 24, 2024 · d49d18c · d49d18c
1 parent 0847e1d
commit d49d18c
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Showing 2 changed files with 10 additions and 8 deletions.
diff --git a/Sources/MetalComputeTools/Kernels/IntegralImage/IntegralImage.metal b/Sources/MetalComputeTools/Kernels/IntegralImage/IntegralImage.metal
@@ -26,7 +26,7 @@ void integralImage(
             const auto currentValue = source.read(currentPosition);
             const auto resultValue = previousValue + currentValue;
             destination.write(resultValue, currentPosition);
-            previousValue = currentValue;
+            previousValue = resultValue;
         }
     } else {
         if (!deviceSupportsNonuniformThreadgroups) {
@@ -42,7 +42,7 @@ void integralImage(
             const auto currentValue = source.read(currentPosition);
             const auto resultValue = previousValue + currentValue;
             destination.write(resultValue, currentPosition);
-            previousValue = currentValue;
+            previousValue = resultValue;
         }
     }
 }

diff --git a/Tests/MetalComputeToolsTests/IntegralImageTests.swift b/Tests/MetalComputeToolsTests/IntegralImageTests.swift
@@ -35,7 +35,7 @@ final class IntegralImageTests: XCTestCase {
             usage: [.shaderRead, .shaderRead]
         )
 
-        let sourceValues = [Float32](repeating: .random(0, 0.3), count: 16)
+        let sourceValues = [Float32](repeating: 0.1, count: 16)
         sourceValues.withUnsafeBufferPointer {
             if let baseAddress = $0.baseAddress {
                 self.source.replace(
@@ -53,24 +53,26 @@ final class IntegralImageTests: XCTestCase {
             for column in 0 ..< 4 {
                 let position = row * 4 + column
                 let currentValue = sourceValues[position]
-                self.expectedResult[position] = currentValue + previousValue
-                previousValue = currentValue
+                let resulValue = currentValue + previousValue
+                self.expectedResult[position] = resulValue
+                previousValue = resulValue
             }
         }
         for column in 0 ..< 4 {
             var previousValue: Float32 = 0
             for row in 0 ..< 4 {
                 let position = row * 4 + column
                 let currentValue = self.expectedResult[position]
-                self.expectedResult[position] = currentValue + previousValue
-                previousValue = currentValue
+                let resulValue = currentValue + previousValue
+                self.expectedResult[position] = resulValue
+                previousValue = resulValue
             }
         }
     }
 
     // MARK: - Testing
 
-    func testEuclideanDistance() throws {
+    func testIntegralImage() throws {
         try self.context.scheduleAndWait { commandBuffer in
             self.integralImageFloat(
                 source: self.source,