Primitives: fix a missing face in cylinder and cone primitives.

doc/changelog.dox

@@ -55,6 +55,12 @@ See also:
     imported data instead of going through a converter plugin if you specify
     `--converter raw`
 
+@subsection changelog-latest-bugfixes Bug fixes
+
+-   The @ref Primitives::cylinderSolid() and @ref Primitives::coneSolid()
+    primitives were missing a face when both caps and texture coordinates were
+    enabled (see [mosra/magnum#386](https://github.com/mosra/magnum/issues/386))
+
 @section changelog-2019-10 2019.10
 
 Released 2019-10-24, tagged as

src/Magnum/Primitives/Cone.cpp

@@ -52,9 +52,14 @@ Trade::MeshData3D coneSolid(const UnsignedInt rings, const UnsignedInt segments,
     /* Vertex rings */
     cone.cylinderVertexRings(rings+1, -halfLength, {-1.0f/rings, length/rings}, textureCoordsV, length/(rings*(flags & ConeFlag::CapEnd ? length + 1.0f : length)));
 
-    /* Faces */
+    /* Faces. Account for the extra vertices for caps and texture coords. */
     if(flags & ConeFlag::CapEnd) cone.bottomFaceRing();
-    cone.faceRings(rings, flags & ConeFlag::CapEnd ? (1 + segments) : 0);
+    if(flags >= (ConeFlag::CapEnd|ConeFlag::GenerateTextureCoords))
+        cone.faceRings(rings, 2 + segments);
+    else if(flags & ConeFlag::CapEnd)
+        cone.faceRings(rings, 1 + segments);
+    else
+        cone.faceRings(rings, 0);
 
     return cone.finalize();
 }

src/Magnum/Primitives/Cylinder.cpp

@@ -58,9 +58,14 @@ Trade::MeshData3D cylinderSolid(const UnsignedInt rings, const UnsignedInt segme
         cylinder.capVertex(halfLength, 1.0f, 1.0f);
     }
 
-    /* Faces */
+    /* Faces. Account for the extra vertices for caps and texture coords. */
     if(flags & CylinderFlag::CapEnds) cylinder.bottomFaceRing();
-    cylinder.faceRings(rings, flags & CylinderFlag::CapEnds ? (1 + segments) : 0);
+    if(flags >= (CylinderFlag::CapEnds|CylinderFlag::GenerateTextureCoords))
+        cylinder.faceRings(rings, 2 + segments);
+    else if(flags & CylinderFlag::CapEnds)
+        cylinder.faceRings(rings, 1 + segments);
+    else
+        cylinder.faceRings(rings, 0);
     if(flags & CylinderFlag::CapEnds) cylinder.topFaceRing();
 
     return cylinder.finalize();

src/Magnum/Primitives/Test/ConeTest.cpp

@@ -286,11 +286,11 @@ void ConeTest::solidWithTextureCoordsAndCaps() {
     }), TestSuite::Compare::Container);
 
     /* Faces of the caps and sides do not share any vertices due to different
-       normals */
+       normals, each ring has an extra vertex for texture coords */
     CORRADE_COMPARE_AS(cone.indices(), (std::vector<UnsignedInt>{
          0,  2,  1,  0,  3,  2,  0,  4,  3,
-         4,  5,  9,  4,  9,  8,  5,  6, 10,  5, 10,  9,  6,  7, 11,  6, 11, 10,
-         8,  9, 13,  8, 13, 12,  9, 10, 14,  9, 14, 13, 10, 11, 15, 10, 15, 14
+         5,  6, 10,  5, 10,  9,  6,  7, 11,  6, 11, 10,  7,  8, 12,  7, 12, 11,
+         9, 10, 14,  9, 14, 13, 10, 11, 15, 10, 15, 14, 11, 12, 16, 11, 16, 15
     }), TestSuite::Compare::Container);
 }
 

src/Magnum/Primitives/Test/CylinderTest.cpp

@@ -320,11 +320,11 @@ void CylinderTest::solidWithTextureCoordsAndCaps() {
     }), TestSuite::Compare::Container);
 
     /* Faces of the caps and sides do not share any vertices due to different
-       normals */
+       normals, each ring has an extra vertex for texture coords */
     CORRADE_COMPARE_AS(cylinder.indices(), (std::vector<UnsignedInt>{
          0,  2,  1,  0,  3,  2,  0,  4,  3,
-         4,  5,  9,  4,  9,  8,  5,  6, 10,  5, 10,  9,  6,  7, 11,  6, 11, 10,
-         8,  9, 13,  8, 13, 12,  9, 10, 14,  9, 14, 13, 10, 11, 15, 10, 15, 14,
+         5,  6, 10,  5, 10,  9,  6,  7, 11,  6, 11, 10,  7,  8, 12,  7, 12, 11,
+         9, 10, 14,  9, 14, 13, 10, 11, 15, 10, 15, 14, 11, 12, 16, 11, 16, 15,
         17, 18, 21, 18, 19, 21, 19, 20, 21
     }), TestSuite::Compare::Container);
 }