DebugTools: support half-float formats in CompareImage.

doc/changelog.dox

@@ -209,6 +209,11 @@ See also:
 
 @subsection changelog-latest-changes Changes and improvements
 
+@subsubsection changelog-latest-changes-debugtools DebugTools library
+
+-   @ref DebugTools::CompareImage now supports comparing half-float pixel
+    formats as well
+
 @subsubsection changelog-latest-changes-gl GL library
 
 -   The @ref GL::Context class got significantly optimized in terms of compile

src/Magnum/DebugTools/CompareImage.cpp

@@ -38,6 +38,7 @@
 #include "Magnum/ImageView.h"
 #include "Magnum/PixelFormat.h"
 #include "Magnum/Math/Functions.h"
+#include "Magnum/Math/Half.h"
 #include "Magnum/Math/Color.h"
 #include "Magnum/Math/Algorithms/KahanSum.h"
 #include "Magnum/Trade/AbstractImageConverter.h"
@@ -166,6 +167,10 @@ std::tuple<Containers::Array<Float>, Float, Float> calculateImageDelta(const Pix
         _c(RG32I, 2, Int)
         _c(RGB32I, 3, Int)
         _c(RGBA32I, 4, Int)
+        _c(R16F, 1, Half)
+        _c(RG16F, 2, Half)
+        _c(RGB16F, 3, Half)
+        _c(RGBA16F, 4, Half)
         _d(R32F, Depth32F, 1, Float)
         _c(RG32F, 2, Float)
         _c(RGB32F, 3, Float)
@@ -176,11 +181,6 @@ std::tuple<Containers::Array<Float>, Float, Float> calculateImageDelta(const Pix
         #undef _d
         #undef _c
 
-        case PixelFormat::R16F:
-        case PixelFormat::RG16F:
-        case PixelFormat::RGB16F:
-        case PixelFormat::RGBA16F:
-            CORRADE_ASSERT_UNREACHABLE("DebugTools::CompareImage: half-float formats are not supported yet", {});
         case PixelFormat::Depth16UnormStencil8UI:
         case PixelFormat::Depth24UnormStencil8UI:
         case PixelFormat::Depth32FStencil8UI:
@@ -311,6 +311,10 @@ void printPixelAt(Debug& out, const Containers::StridedArrayView3D<const char>&
         _c(RG32I, 2, Int)
         _c(RGB32I, 3, Int)
         _c(RGBA32I, 4, Int)
+        _c(R16F, 1, Half)
+        _c(RG16F, 2, Half)
+        _c(RGB16F, 3, Half)
+        _c(RGBA16F, 4, Half)
         _d(R32F, Depth32F, 1, Float)
         _c(RG32F, 2, Float)
         _c(RGB32F, 3, Float)
@@ -331,10 +335,6 @@ void printPixelAt(Debug& out, const Containers::StridedArrayView3D<const char>&
             out << *reinterpret_cast<const Color4ub*>(pixel);
             break;
 
-        case PixelFormat::R16F:
-        case PixelFormat::RG16F:
-        case PixelFormat::RGB16F:
-        case PixelFormat::RGBA16F:
         case PixelFormat::Depth16UnormStencil8UI:
         case PixelFormat::Depth24UnormStencil8UI:
         case PixelFormat::Depth32FStencil8UI:

src/Magnum/DebugTools/CompareImage.h

@@ -236,14 +236,14 @@ Supports the following formats:
     @ref PixelFormat::RGBA32UI and their one-/two-/three-component versions
 -   @ref PixelFormat::RGBA8I, @ref PixelFormat::RGBA16I,
     @ref PixelFormat::RGBA32I and their one-/two-/three-component versions
+-   @ref PixelFormat::RGBA16F and its one-/two-/three-component versions
 -   @ref PixelFormat::RGBA32F and its one-/two-/three-component versions
 
-@ref PixelFormat::RGBA16F and other half-float formats are not supported at the
+Packed depth/stencil formats are not supported at the moment, however you can
-moment. Packed depth/stencil formats are not supported at the moment,
+work around that by making separate depth/stencil pixel views and
-however you can work around that by making separate depth/stencil pixel
+@ref DebugTools-CompareImage-pixels "comparing the views" to a
-views and @ref DebugTools-CompareImage-pixels "comparing those" to a
+depth/stencil-only ground truth images. Implementation-specific pixel formats
-depth/stencil-only ground truth images. Implementation-specific pixel
+can't be supported.
-formats can't be supported.
 
 Supports all @ref PixelStorage parameters. The images don't need to have the
 same pixel storage parameters, meaning you are able to compare different

src/Magnum/DebugTools/Test/CompareImageTest.cpp

@@ -40,8 +40,9 @@
 #include "Magnum/ImageView.h"
 #include "Magnum/PixelFormat.h"
 #include "Magnum/DebugTools/CompareImage.h"
-#include "Magnum/Math/Functions.h"
 #include "Magnum/Math/Color.h"
+#include "Magnum/Math/Functions.h"
+#include "Magnum/Math/Half.h"
 #include "Magnum/Trade/AbstractImageConverter.h"
 #include "Magnum/Trade/AbstractImporter.h"
 
@@ -53,7 +54,6 @@ struct CompareImageTest: TestSuite::Tester {
     explicit CompareImageTest();
 
     void formatUnknown();
-    void formatHalf();
     void formatPackedDepthStencil();
     void formatImplementationSpecific();
 
@@ -70,6 +70,7 @@ struct CompareImageTest: TestSuite::Tester {
     void pixelDelta();
     void pixelDeltaEmpty();
     void pixelDeltaOverflow();
+    void pixelDeltaHalf();
     void pixelDeltaSpecials();
 
     void compareDifferentSize();
@@ -125,7 +126,6 @@ struct CompareImageTest: TestSuite::Tester {
 
 CompareImageTest::CompareImageTest() {
     addTests({&CompareImageTest::formatUnknown,
-              &CompareImageTest::formatHalf,
               &CompareImageTest::formatPackedDepthStencil,
               &CompareImageTest::formatImplementationSpecific,
 
@@ -142,6 +142,7 @@ CompareImageTest::CompareImageTest() {
               &CompareImageTest::pixelDelta,
               &CompareImageTest::pixelDeltaEmpty,
               &CompareImageTest::pixelDeltaOverflow,
+              &CompareImageTest::pixelDeltaHalf,
               &CompareImageTest::pixelDeltaSpecials,
 
               &CompareImageTest::compareDifferentSize,
@@ -218,6 +219,8 @@ CompareImageTest::CompareImageTest() {
        setupExternalPluginManager() function */
 }
 
+using namespace Math::Literals;
+
 const Float ActualRedData[] = {
      0.3f, 1.0f, 0.9f,
      0.9f, 0.6f, 0.2f,
@@ -253,20 +256,6 @@ void CompareImageTest::formatUnknown() {
     CORRADE_COMPARE(out.str(), "DebugTools::CompareImage: unknown format PixelFormat(0xdead)\n");
 }
 
-void CompareImageTest::formatHalf() {
-    #ifdef CORRADE_NO_ASSERT
-    CORRADE_SKIP("CORRADE_NO_ASSERT defined, can't test assertions");
-    #endif
-
-    std::ostringstream out;
-    Error redirectError{&out};
-
-    ImageView2D image{PixelFormat::RG16F, {}};
-    Implementation::calculateImageDelta(image.format(), image.pixels(), image);
-
-    CORRADE_COMPARE(out.str(), "DebugTools::CompareImage: half-float formats are not supported yet\n");
-}
-
 void CompareImageTest::formatPackedDepthStencil() {
     #ifdef CORRADE_NO_ASSERT
     CORRADE_SKIP("CORRADE_NO_ASSERT defined, can't test assertions");
@@ -532,6 +521,36 @@ void CompareImageTest::pixelDeltaOverflow() {
         "          [2,0] Vector(0.9), expected Vector(0.6) (Δ = 0.3)");
 }
 
+const Vector2h ActualHalfData[]{
+    {0.3_h, 1.0_h}, { 0.9_h, 0.9_h},
+    {0.6_h, 0.2_h}, {-0.1_h, 1.0_h},
+};
+
+const Vector2h ExpectedHalfData[]{
+    {0.65_h, 1.0_h}, {0.6_h, 0.91_h},
+    {0.6_h, 0.1_h}, {0.02_h, 0.0_h}
+};
+
+const Float DeltaHalf[] {
+    0.35f/2.0f, 0.31f/2.0f,
+    0.01f/2.0f, 0.22f/2.0f
+};
+
+const ImageView2D ActualHalf{PixelFormat::RG16F, {2, 2}, ActualHalfData};
+const ImageView2D ExpectedHalf{PixelFormat::RG16F, {2, 2}, ExpectedHalfData};
+
+void CompareImageTest::pixelDeltaHalf() {
+    std::ostringstream out;
+    Debug d{&out, Debug::Flag::DisableColors};
+    Implementation::printPixelDeltas(d, DeltaHalf, ActualHalf.format(), ActualHalf.pixels(), ExpectedHalf.pixels(), 0.5f, 0.1f, 10);
+
+    CORRADE_COMPARE(out.str(), "\n"
+        "        Pixels above max/mean threshold:\n"
+        "          [0,0] Vector(0.3, 1), expected Vector(0.6499, 1) (Δ = 0.175)\n"
+        "          [1,0] Vector(0.8999, 0.8999), expected Vector(0.6001, 0.9102) (Δ = 0.155)\n"
+        "          [1,1] Vector(-0.09998, 1), expected Vector(0.02, 0) (Δ = 0.11)");
+}
+
 void CompareImageTest::pixelDeltaSpecials() {
     std::ostringstream out;
     Debug d{&out, Debug::Flag::DisableColors};