From a56134ba330775415dd6148d8667e9a3c7ce2537 Mon Sep 17 00:00:00 2001 From: Malcolm Tyrrell Date: Wed, 15 Jul 2020 09:05:09 +0100 Subject: [PATCH] Drop faces when indices are out of range. --- code/AssetLib/glTF2/glTF2Importer.cpp | 117 +++++++++++++++----------- 1 file changed, 67 insertions(+), 50 deletions(-) diff --git a/code/AssetLib/glTF2/glTF2Importer.cpp b/code/AssetLib/glTF2/glTF2Importer.cpp index 4d740d8c1..1c32b48e2 100644 --- a/code/AssetLib/glTF2/glTF2Importer.cpp +++ b/code/AssetLib/glTF2/glTF2Importer.cpp @@ -298,25 +298,37 @@ void glTF2Importer::ImportMaterials(glTF2::Asset &r) { } } -static inline void SetFace(aiFace &face, int a) { - face.mNumIndices = 1; - face.mIndices = new unsigned int[1]; - face.mIndices[0] = a; +static inline void SetFaceAndAdvance(aiFace*& face, unsigned int numVertices, unsigned int a) { + if (a >= numVertices) { + return; + } + face->mNumIndices = 1; + face->mIndices = new unsigned int[1]; + face->mIndices[0] = a; + ++face; } -static inline void SetFace(aiFace &face, int a, int b) { - face.mNumIndices = 2; - face.mIndices = new unsigned int[2]; - face.mIndices[0] = a; - face.mIndices[1] = b; +static inline void SetFaceAndAdvance(aiFace*& face, unsigned int numVertices, unsigned int a, unsigned int b) { + if ((a >= numVertices) || (b >= numVertices)) { + return; + } + face->mNumIndices = 2; + face->mIndices = new unsigned int[2]; + face->mIndices[0] = a; + face->mIndices[1] = b; + ++face; } -static inline void SetFace(aiFace &face, int a, int b, int c) { - face.mNumIndices = 3; - face.mIndices = new unsigned int[3]; - face.mIndices[0] = a; - face.mIndices[1] = b; - face.mIndices[2] = c; +static inline void SetFaceAndAdvance(aiFace*& face, unsigned int numVertices, unsigned int a, unsigned int b, unsigned int c) { + if ((a >= numVertices) || (b >= numVertices) || (c >= numVertices)) { + return; + } + face->mNumIndices = 3; + face->mIndices = new unsigned int[3]; + face->mIndices[0] = a; + face->mIndices[1] = b; + face->mIndices[2] = c; + ++face; } #ifdef ASSIMP_BUILD_DEBUG @@ -486,6 +498,7 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) { } aiFace *faces = nullptr; + aiFace *facePtr = nullptr; size_t nFaces = 0; if (prim.indices) { @@ -497,9 +510,9 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) { switch (prim.mode) { case PrimitiveMode_POINTS: { nFaces = count; - faces = new aiFace[nFaces]; + facePtr = faces = new aiFace[nFaces]; for (unsigned int i = 0; i < count; ++i) { - SetFace(faces[i], data.GetUInt(i)); + SetFaceAndAdvance(facePtr, aim->mNumVertices, data.GetUInt(i)); } break; } @@ -510,9 +523,9 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) { ASSIMP_LOG_WARN("The number of vertices was not compatible with the LINES mode. Some vertices were dropped."); count = nFaces * 2; } - faces = new aiFace[nFaces]; + facePtr = faces = new aiFace[nFaces]; for (unsigned int i = 0; i < count; i += 2) { - SetFace(faces[i / 2], data.GetUInt(i), data.GetUInt(i + 1)); + SetFaceAndAdvance(facePtr, aim->mNumVertices, data.GetUInt(i), data.GetUInt(i + 1)); } break; } @@ -520,13 +533,13 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) { case PrimitiveMode_LINE_LOOP: case PrimitiveMode_LINE_STRIP: { nFaces = count - ((prim.mode == PrimitiveMode_LINE_STRIP) ? 1 : 0); - faces = new aiFace[nFaces]; - SetFace(faces[0], data.GetUInt(0), data.GetUInt(1)); + facePtr = faces = new aiFace[nFaces]; + SetFaceAndAdvance(facePtr, aim->mNumVertices, data.GetUInt(0), data.GetUInt(1)); for (unsigned int i = 2; i < count; ++i) { - SetFace(faces[i - 1], faces[i - 2].mIndices[1], data.GetUInt(i)); + SetFaceAndAdvance(facePtr, aim->mNumVertices, faces[i - 2].mIndices[1], data.GetUInt(i)); } if (prim.mode == PrimitiveMode_LINE_LOOP) { // close the loop - SetFace(faces[count - 1], faces[count - 2].mIndices[1], faces[0].mIndices[0]); + SetFaceAndAdvance(facePtr, aim->mNumVertices, faces[count - 2].mIndices[1], faces[0].mIndices[0]); } break; } @@ -537,33 +550,33 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) { ASSIMP_LOG_WARN("The number of vertices was not compatible with the TRIANGLES mode. Some vertices were dropped."); count = nFaces * 3; } - faces = new aiFace[nFaces]; + facePtr = faces = new aiFace[nFaces]; for (unsigned int i = 0; i < count; i += 3) { - SetFace(faces[i / 3], data.GetUInt(i), data.GetUInt(i + 1), data.GetUInt(i + 2)); + SetFaceAndAdvance(facePtr, aim->mNumVertices, data.GetUInt(i), data.GetUInt(i + 1), data.GetUInt(i + 2)); } break; } case PrimitiveMode_TRIANGLE_STRIP: { nFaces = count - 2; - faces = new aiFace[nFaces]; + facePtr = faces = new aiFace[nFaces]; for (unsigned int i = 0; i < nFaces; ++i) { //The ordering is to ensure that the triangles are all drawn with the same orientation if ((i + 1) % 2 == 0) { //For even n, vertices n + 1, n, and n + 2 define triangle n - SetFace(faces[i], data.GetUInt(i + 1), data.GetUInt(i), data.GetUInt(i + 2)); + SetFaceAndAdvance(facePtr, aim->mNumVertices, data.GetUInt(i + 1), data.GetUInt(i), data.GetUInt(i + 2)); } else { //For odd n, vertices n, n+1, and n+2 define triangle n - SetFace(faces[i], data.GetUInt(i), data.GetUInt(i + 1), data.GetUInt(i + 2)); + SetFaceAndAdvance(facePtr, aim->mNumVertices, data.GetUInt(i), data.GetUInt(i + 1), data.GetUInt(i + 2)); } } break; } case PrimitiveMode_TRIANGLE_FAN: nFaces = count - 2; - faces = new aiFace[nFaces]; - SetFace(faces[0], data.GetUInt(0), data.GetUInt(1), data.GetUInt(2)); + facePtr = faces = new aiFace[nFaces]; + SetFaceAndAdvance(facePtr, data.GetUInt(0), data.GetUInt(1), data.GetUInt(2)); for (unsigned int i = 1; i < nFaces; ++i) { - SetFace(faces[i], faces[0].mIndices[0], faces[i - 1].mIndices[2], data.GetUInt(i + 2)); + SetFaceAndAdvance(facePtr, aim->mNumVertices, faces[0].mIndices[0], faces[i - 1].mIndices[2], data.GetUInt(i + 2)); } break; } @@ -575,9 +588,9 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) { switch (prim.mode) { case PrimitiveMode_POINTS: { nFaces = count; - faces = new aiFace[nFaces]; + facePtr = faces = new aiFace[nFaces]; for (unsigned int i = 0; i < count; ++i) { - SetFace(faces[i], i); + SetFaceAndAdvance(facePtr, aim->mNumVertices, i); } break; } @@ -588,9 +601,9 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) { ASSIMP_LOG_WARN("The number of vertices was not compatible with the LINES mode. Some vertices were dropped."); count = (unsigned int)nFaces * 2; } - faces = new aiFace[nFaces]; + facePtr = faces = new aiFace[nFaces]; for (unsigned int i = 0; i < count; i += 2) { - SetFace(faces[i / 2], i, i + 1); + SetFaceAndAdvance(facePtr, aim->mNumVertices, i, i + 1); } break; } @@ -598,13 +611,13 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) { case PrimitiveMode_LINE_LOOP: case PrimitiveMode_LINE_STRIP: { nFaces = count - ((prim.mode == PrimitiveMode_LINE_STRIP) ? 1 : 0); - faces = new aiFace[nFaces]; - SetFace(faces[0], 0, 1); + facePtr = faces = new aiFace[nFaces]; + SetFaceAndAdvance(facePtr, aim->mNumVertices, 0, 1); for (unsigned int i = 2; i < count; ++i) { - SetFace(faces[i - 1], faces[i - 2].mIndices[1], i); + SetFaceAndAdvance(facePtr, aim->mNumVertices, faces[i - 2].mIndices[1], i); } if (prim.mode == PrimitiveMode_LINE_LOOP) { // close the loop - SetFace(faces[count - 1], faces[count - 2].mIndices[1], faces[0].mIndices[0]); + SetFaceAndAdvance(facePtr, aim->mNumVertices, faces[count - 2].mIndices[1], faces[0].mIndices[0]); } break; } @@ -615,42 +628,46 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) { ASSIMP_LOG_WARN("The number of vertices was not compatible with the TRIANGLES mode. Some vertices were dropped."); count = (unsigned int)nFaces * 3; } - faces = new aiFace[nFaces]; + facePtr = faces = new aiFace[nFaces]; for (unsigned int i = 0; i < count; i += 3) { - SetFace(faces[i / 3], i, i + 1, i + 2); + SetFaceAndAdvance(facePtr, aim->mNumVertices, i, i + 1, i + 2); } break; } case PrimitiveMode_TRIANGLE_STRIP: { nFaces = count - 2; - faces = new aiFace[nFaces]; + facePtr = faces = new aiFace[nFaces]; for (unsigned int i = 0; i < nFaces; ++i) { //The ordering is to ensure that the triangles are all drawn with the same orientation if ((i + 1) % 2 == 0) { //For even n, vertices n + 1, n, and n + 2 define triangle n - SetFace(faces[i], i + 1, i, i + 2); + SetFaceAndAdvance(facePtr, aim->mNumVertices, i + 1, i, i + 2); } else { //For odd n, vertices n, n+1, and n+2 define triangle n - SetFace(faces[i], i, i + 1, i + 2); + SetFaceAndAdvance(facePtr, aim->mNumVertices, i, i + 1, i + 2); } } break; } case PrimitiveMode_TRIANGLE_FAN: nFaces = count - 2; - faces = new aiFace[nFaces]; - SetFace(faces[0], 0, 1, 2); + facePtr = faces = new aiFace[nFaces]; + SetFaceAndAdvance(facePtr, aim->mNumVertices, 0, 1, 2); for (unsigned int i = 1; i < nFaces; ++i) { - SetFace(faces[i], faces[0].mIndices[0], faces[i - 1].mIndices[2], i + 2); + SetFaceAndAdvance(facePtr, aim->mNumVertices, faces[0].mIndices[0], faces[i - 1].mIndices[2], i + 2); } break; } } - if (nullptr != faces) { + if (faces) { aim->mFaces = faces; - aim->mNumFaces = static_cast(nFaces); - ai_assert(CheckValidFacesIndices(faces, static_cast(nFaces), aim->mNumVertices)); + const unsigned int actualNumFaces = facePtr - faces; + if (actualNumFaces < nFaces) { + ASSIMP_LOG_WARN("Some faces had out-of-range indices. Those faces were dropped."); + } + aim->mNumFaces = actualNumFaces; + ai_assert(CheckValidFacesIndices(faces, actualNumFaces, aim->mNumVertices)); } if (prim.material) {