diff --git a/src/r_data/models/models_obj.cpp b/src/r_data/models/models_obj.cpp index 4cc5ffa17..d56d994a0 100644 --- a/src/r_data/models/models_obj.cpp +++ b/src/r_data/models/models_obj.cpp @@ -101,8 +101,9 @@ bool FOBJModel::Load(const char* fn, int lumpnum, const char* buffer, int length FTextureID curMtl = FNullTextureID(); OBJSurface *curSurface = nullptr; - int aggSurfFaceCount = 0; - int curSurfFaceCount = 0; + unsigned int aggSurfFaceCount = 0; + unsigned int curSurfFaceCount = 0; + unsigned int curSmoothGroup = 0; while(sc.GetString()) { @@ -186,9 +187,25 @@ bool FOBJModel::Load(const char* fn, int lumpnum, const char* buffer, int length sc.UnGet(); // No 4th side, move back } } + face.smoothGroup = curSmoothGroup; faces.Push(face); curSurfFaceCount += 1; } + else if (sc.Compare("s")) + { + sc.MustGetString(); + if (sc.Compare("off")) + { + curSmoothGroup = 0; + } + else + { + sc.UnGet(); + sc.MustGetNumber(); + curSmoothGroup = sc.Number; + hasSmoothGroups = hasSmoothGroups || curSmoothGroup > 0; + } + } } sc.Close(); @@ -277,11 +294,13 @@ bool FOBJModel::ParseFaceSide(const FString &sideStr, OBJFace &face, int sidx) else { side.normref = -1; + hasMissingNormals = true; } } else { side.normref = -1; + hasMissingNormals = true; } } else @@ -289,6 +308,7 @@ bool FOBJModel::ParseFaceSide(const FString &sideStr, OBJFace &face, int sidx) origIdx = atoi(sideStr.GetChars()); side.vertref = ResolveIndex(origIdx, FaceElement::VertexIndex); side.normref = -1; + hasMissingNormals = true; side.uvref = -1; } face.sides[sidx] = side; @@ -348,6 +368,11 @@ void FOBJModel::BuildVertexBuffer(FModelRenderer *renderer) surfaces[i].vbStart = vbufsize; vbufsize += surfaces[i].numTris * 3; } + // Initialize/populate vertFaces + if (hasMissingNormals && hasSmoothGroups) + { + AddVertFaces(); + } auto vbuf = renderer->CreateVertexBuffer(false,true); SetVertexBuffer(renderer, vbuf); @@ -372,39 +397,40 @@ void FOBJModel::BuildVertexBuffer(FModelRenderer *renderer) FVector3 curVvec = RealignVector(verts[vidx]); FVector2 curUvec = FixUV(uvs[uvidx]); - FVector3 *nvec = nullptr; + FVector3 nvec; mdv->Set(curVvec.X, curVvec.Y, curVvec.Z, curUvec.X, curUvec.Y); if (nidx >= 0 && (unsigned int)nidx < norms.Size()) { - nvec = new FVector3(RealignVector(norms[nidx])); + nvec = RealignVector(norms[nidx]); } else { - // https://www.khronos.org/opengl/wiki/Calculating_a_Surface_Normal - // Find other sides of triangle - auto nextSidx = side + 2; - if (nextSidx >= 3) nextSidx -= 3; - - auto lastSidx = side + 1; - if (lastSidx >= 3) lastSidx -= 3; - - OBJFaceSide &nextSide = surfaces[i].tris[j].sides[nextSidx]; - OBJFaceSide &lastSide = surfaces[i].tris[j].sides[lastSidx]; - - // Cross-multiply the U-vector and V-vector - FVector3 uvec = RealignVector(verts[nextSide.vertref]) - curVvec; - FVector3 vvec = RealignVector(verts[lastSide.vertref]) - curVvec; - - nvec = new FVector3(uvec ^ vvec); + if (surfaces[i].tris[j].smoothGroup == 0) + { + nvec = CalculateNormalFlat(i, j); + } + else + { + nvec = CalculateNormalSmooth(vidx, surfaces[i].tris[j].smoothGroup); + } } - mdv->SetNormal(nvec->X, nvec->Y, nvec->Z); - delete nvec; + mdv->SetNormal(nvec.X, nvec.Y, nvec.Z); } } delete[] surfaces[i].tris; } + + // Destroy vertFaces + if (hasMissingNormals && hasSmoothGroups) + { + for (size_t i = 0; i < verts.Size(); i++) + { + vertFaces[i].Clear(); + } + delete[] vertFaces; + } vbuf->UnlockVertexBuffer(); } @@ -432,6 +458,7 @@ void FOBJModel::ConstructSurfaceTris(OBJSurface &surf) surf.tris[triIdx].sideCount = 3; if (faces[i].sideCount == 3) { + surf.tris[triIdx].smoothGroup = faces[i].smoothGroup; memcpy(surf.tris[triIdx].sides, faces[i].sides, sizeof(OBJFaceSide) * 3); } else if (faces[i].sideCount == 4) // Triangulate face @@ -443,6 +470,7 @@ void FOBJModel::ConstructSurfaceTris(OBJSurface &surf) delete[] triangulated; triIdx += 1; // Filling out two faces } + DPrintf(DMSG_SPAMMY, "Smooth group: %d\n", surf.tris[triIdx].smoothGroup); } } @@ -455,7 +483,9 @@ void FOBJModel::ConstructSurfaceTris(OBJSurface &surf) void FOBJModel::TriangulateQuad(const OBJFace &quad, OBJFace *tris) { tris[0].sideCount = 3; + tris[0].smoothGroup = quad.smoothGroup; tris[1].sideCount = 3; + tris[1].smoothGroup = quad.smoothGroup; int tsidx[2][3] = {{0, 1, 3}, {1, 2, 3}}; @@ -470,6 +500,26 @@ void FOBJModel::TriangulateQuad(const OBJFace &quad, OBJFace *tris) } } +/** + * Add the vertices of all surfaces' triangles to the array of vertex->triangle references + */ +void FOBJModel::AddVertFaces() { + // Initialize and populate vertFaces - this array stores references to triangles per vertex + vertFaces = new TArray[verts.Size()]; + for (size_t i = 0; i < surfaces.Size(); i++) + { + for (size_t j = 0; j < surfaces[i].numTris; j++) + { + OBJTriRef otr = OBJTriRef(i, j); + for (size_t k = 0; k < surfaces[i].tris[j].sideCount; k++) + { + int vidx = surfaces[i].tris[j].sides[k].vertref; + vertFaces[vidx].Push(otr); + } + } + } +} + /** * Re-align a vector to match MD3 alignment * @@ -494,6 +544,65 @@ inline FVector2 FOBJModel::FixUV(FVector2 vecToRealign) return vecToRealign; } +/** + * Calculate the surface normal for a triangle + * + * @param surfIdx The surface index + * @param triIdx The triangle Index + * @return The surface normal vector + */ +FVector3 FOBJModel::CalculateNormalFlat(unsigned int surfIdx, unsigned int triIdx) +{ + // https://www.khronos.org/opengl/wiki/Calculating_a_Surface_Normal + int curVert = surfaces[surfIdx].tris[triIdx].sides[0].vertref; + int nextVert = surfaces[surfIdx].tris[triIdx].sides[2].vertref; + int lastVert = surfaces[surfIdx].tris[triIdx].sides[1].vertref; + + // Cross-multiply the U-vector and V-vector + FVector3 curVvec = RealignVector(verts[curVert]); + FVector3 uvec = RealignVector(verts[nextVert]) - curVvec; + FVector3 vvec = RealignVector(verts[lastVert]) - curVvec; + + return uvec ^ vvec; +} + +/** + * Calculate the surface normal for a triangle + * + * @param otr A reference to the surface, and a triangle within that surface, as an OBJTriRef + * @return The surface normal vector + */ +FVector3 FOBJModel::CalculateNormalFlat(OBJTriRef otr) +{ + return CalculateNormalFlat(otr.surf, otr.tri); +} + +/** + * Calculate the normal of a vertex in a specific smooth group + * + * @param vidx The index of the vertex in the array of vertices + * @param smoothGroup The smooth group number + */ +FVector3 FOBJModel::CalculateNormalSmooth(unsigned int vidx, unsigned int smoothGroup) +{ + unsigned int connectedFaces = 0; + TArray& vTris = vertFaces[vidx]; + + FVector3 vNormal(0,0,0); + for (size_t face = 0; face < vTris.Size(); face++) + { + OBJFace& tri = surfaces[vTris[face].surf].tris[vTris[face].tri]; + if (tri.smoothGroup == smoothGroup) + { + FVector3 fNormal = CalculateNormalFlat(vTris[face]); + connectedFaces += 1; + vNormal += fNormal; + } + } + vNormal /= connectedFaces; + return vNormal; +} + /** * Find the index of the frame with the given name * diff --git a/src/r_data/models/models_obj.h b/src/r_data/models/models_obj.h index d6d68a58e..01a6e03cf 100644 --- a/src/r_data/models/models_obj.h +++ b/src/r_data/models/models_obj.h @@ -30,6 +30,8 @@ class FOBJModel : public FModel { private: const char *newSideSep = "$"; // OBJ side separator is /, which is parsed as a line comment by FScanner if two of them are next to each other. + bool hasMissingNormals; + bool hasSmoothGroups; enum class FaceElement { @@ -38,6 +40,14 @@ private: VNormalIndex }; + struct OBJTriRef + { + unsigned int surf; + unsigned int tri; + OBJTriRef(): surf(0), tri(0) {} + OBJTriRef(unsigned int surf, unsigned int tri): surf(surf), tri(tri) {} + bool operator== (OBJTriRef other) { return surf == other.surf && tri == other.tri; } + }; struct OBJFaceSide { int vertref; @@ -47,7 +57,9 @@ private: struct OBJFace { unsigned int sideCount; + unsigned int smoothGroup; OBJFaceSide sides[4]; + OBJFace(): sideCount(0), smoothGroup(0) {} }; struct OBJSurface // 1 surface per 'usemtl' { @@ -66,16 +78,21 @@ private: TArray faces; TArray surfaces; FScanner sc; + TArray* vertFaces; + int ResolveIndex(int origIndex, FaceElement el); template void ParseVector(TArray &array); bool ParseFaceSide(const FString &side, OBJFace &face, int sidx); void ConstructSurfaceTris(OBJSurface &surf); - int ResolveIndex(int origIndex, FaceElement el); + void AddVertFaces(); void TriangulateQuad(const OBJFace &quad, OBJFace *tris); FVector3 RealignVector(FVector3 vecToRealign); FVector2 FixUV(FVector2 vecToRealign); + FVector3 CalculateNormalFlat(unsigned int surfIdx, unsigned int triIdx); + FVector3 CalculateNormalFlat(OBJTriRef otr); + FVector3 CalculateNormalSmooth(unsigned int vidx, unsigned int smoothGroup); public: - FOBJModel() {} + FOBJModel(): hasMissingNormals(false), hasSmoothGroups(false), vertFaces(nullptr) {} ~FOBJModel(); bool Load(const char* fn, int lumpnum, const char* buffer, int length) override; int FindFrame(const char* name) override;