1 files changed, 249 insertions, 0 deletions
diff --git a/libs/assimp/code/AssetLib/Terragen/TerragenLoader.cpp b/libs/assimp/code/AssetLib/Terragen/TerragenLoader.cpp
new file mode 100644
index 0000000..c9c91db
--- /dev/null
+++ b/libs/assimp/code/AssetLib/Terragen/TerragenLoader.cpp
@@ -0,0 +1,249 @@
+/*
+---------------------------------------------------------------------------
+Open Asset Import Library (assimp)
+---------------------------------------------------------------------------
+
+Copyright (c) 2006-2022, assimp team
+
+All rights reserved.
+
+Redistribution and use of this software in source and binary forms,
+with or without modification, are permitted provided that the following
+conditions are met:
+
+* Redistributions of source code must retain the above
+  copyright notice, this list of conditions and the
+  following disclaimer.
+
+* Redistributions in binary form must reproduce the above
+  copyright notice, this list of conditions and the
+  following disclaimer in the documentation and/or other
+  materials provided with the distribution.
+
+* Neither the name of the assimp team, nor the names of its
+  contributors may be used to endorse or promote products
+  derived from this software without specific prior
+  written permission of the assimp team.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+---------------------------------------------------------------------------
+*/
+
+/** @file Implementation of the Terragen importer class */
+
+#ifndef ASSIMP_BUILD_NO_TERRAGEN_IMPORTER
+
+#include "TerragenLoader.h"
+#include <assimp/StreamReader.h>
+#include <assimp/importerdesc.h>
+#include <assimp/scene.h>
+#include <assimp/DefaultLogger.hpp>
+#include <assimp/IOSystem.hpp>
+#include <assimp/Importer.hpp>
+
+using namespace Assimp;
+
+static const aiImporterDesc desc = {
+    "Terragen Heightmap Importer",
+    "",
+    "",
+    "http://www.planetside.co.uk/",
+    aiImporterFlags_SupportBinaryFlavour,
+    0,
+    0,
+    0,
+    0,
+    "ter"
+};
+
+// ------------------------------------------------------------------------------------------------
+// Constructor to be privately used by Importer
+TerragenImporter::TerragenImporter() :
+        configComputeUVs(false) {
+    // empty
+}
+
+// ------------------------------------------------------------------------------------------------
+// Destructor, private as well
+TerragenImporter::~TerragenImporter() {
+    // empty
+}
+
+// ------------------------------------------------------------------------------------------------
+// Returns whether the class can handle the format of the given file.
+bool TerragenImporter::CanRead(const std::string &pFile, IOSystem *pIOHandler, bool /*checkSig*/) const {
+    static const char *tokens[] = { "terragen" };
+    return SearchFileHeaderForToken(pIOHandler, pFile, tokens, AI_COUNT_OF(tokens));
+}
+
+// ------------------------------------------------------------------------------------------------
+// Build a string of all file extensions supported
+const aiImporterDesc *TerragenImporter::GetInfo() const {
+    return &desc;
+}
+
+// ------------------------------------------------------------------------------------------------
+// Setup import properties
+void TerragenImporter::SetupProperties(const Importer *pImp) {
+    // AI_CONFIG_IMPORT_TER_MAKE_UVS
+    configComputeUVs = (0 != pImp->GetPropertyInteger(AI_CONFIG_IMPORT_TER_MAKE_UVS, 0));
+}
+
+// ------------------------------------------------------------------------------------------------
+// Imports the given file into the given scene structure.
+void TerragenImporter::InternReadFile(const std::string &pFile,
+        aiScene *pScene, IOSystem *pIOHandler) {
+    IOStream *file = pIOHandler->Open(pFile, "rb");
+
+    // Check whether we can read from the file
+    if (file == nullptr)
+        throw DeadlyImportError("Failed to open TERRAGEN TERRAIN file ", pFile, ".");
+
+    // Construct a stream reader to read all data in the correct endianness
+    StreamReaderLE reader(file);
+    if (reader.GetRemainingSize() < 16)
+        throw DeadlyImportError("TER: file is too small");
+
+    // Check for the existence of the two magic strings 'TERRAGEN' and 'TERRAIN '
+    if (::strncmp((const char *)reader.GetPtr(), AI_TERR_BASE_STRING, 8))
+        throw DeadlyImportError("TER: Magic string \'TERRAGEN\' not found");
+
+    if (::strncmp((const char *)reader.GetPtr() + 8, AI_TERR_TERRAIN_STRING, 8))
+        throw DeadlyImportError("TER: Magic string \'TERRAIN\' not found");
+
+    unsigned int x = 0, y = 0, mode = 0;
+
+    aiNode *root = pScene->mRootNode = new aiNode();
+    root->mName.Set("<TERRAGEN.TERRAIN>");
+
+    // Default scaling is 30
+    root->mTransformation.a1 = root->mTransformation.b2 = root->mTransformation.c3 = 30.f;
+
+    // Now read all chunks until we're finished or an EOF marker is encountered
+    reader.IncPtr(16);
+    while (reader.GetRemainingSize() >= 4) {
+        const char *head = (const char *)reader.GetPtr();
+        reader.IncPtr(4);
+
+        // EOF, break in every case
+        if (!::strncmp(head, AI_TERR_EOF_STRING, 4))
+            break;
+
+        // Number of x-data points
+        if (!::strncmp(head, AI_TERR_CHUNK_XPTS, 4)) {
+            x = (uint16_t)reader.GetI2();
+        }
+        // Number of y-data points
+        else if (!::strncmp(head, AI_TERR_CHUNK_YPTS, 4)) {
+            y = (uint16_t)reader.GetI2();
+        }
+        // Squared terrains width-1.
+        else if (!::strncmp(head, AI_TERR_CHUNK_SIZE, 4)) {
+            x = y = (uint16_t)reader.GetI2() + 1;
+        }
+        // terrain scaling
+        else if (!::strncmp(head, AI_TERR_CHUNK_SCAL, 4)) {
+            root->mTransformation.a1 = reader.GetF4();
+            root->mTransformation.b2 = reader.GetF4();
+            root->mTransformation.c3 = reader.GetF4();
+        }
+        // mapping == 1: earth radius
+        else if (!::strncmp(head, AI_TERR_CHUNK_CRAD, 4)) {
+            reader.GetF4();
+        }
+        // mapping mode
+        else if (!::strncmp(head, AI_TERR_CHUNK_CRVM, 4)) {
+            mode = reader.GetI1();
+            if (0 != mode)
+                ASSIMP_LOG_ERROR("TER: Unsupported mapping mode, a flat terrain is returned");
+        }
+        // actual terrain data
+        else if (!::strncmp(head, AI_TERR_CHUNK_ALTW, 4)) {
+            float hscale = (float)reader.GetI2() / 65536;
+            float bheight = (float)reader.GetI2();
+
+            if (!hscale) hscale = 1;
+
+            // Ensure we have enough data
+            if (reader.GetRemainingSize() < x * y * 2)
+                throw DeadlyImportError("TER: ALTW chunk is too small");
+
+            if (x <= 1 || y <= 1)
+                throw DeadlyImportError("TER: Invalid terrain size");
+
+            // Allocate the output mesh
+            pScene->mMeshes = new aiMesh *[pScene->mNumMeshes = 1];
+            aiMesh *m = pScene->mMeshes[0] = new aiMesh();
+
+            // We return quads
+            aiFace *f = m->mFaces = new aiFace[m->mNumFaces = (x - 1) * (y - 1)];
+            aiVector3D *pv = m->mVertices = new aiVector3D[m->mNumVertices = m->mNumFaces * 4];
+
+            aiVector3D *uv(nullptr);
+            float step_y(0.0f), step_x(0.0f);
+            if (configComputeUVs) {
+                uv = m->mTextureCoords[0] = new aiVector3D[m->mNumVertices];
+                step_y = 1.f / y;
+                step_x = 1.f / x;
+            }
+            const int16_t *data = (const int16_t *)reader.GetPtr();
+
+            for (unsigned int yy = 0, t = 0; yy < y - 1; ++yy) {
+                for (unsigned int xx = 0; xx < x - 1; ++xx, ++f) {
+
+                    // make verts
+                    const float fy = (float)yy, fx = (float)xx;
+                    unsigned tmp, tmp2;
+                    *pv++ = aiVector3D(fx, fy, (float)data[(tmp2 = x * yy) + xx] * hscale + bheight);
+                    *pv++ = aiVector3D(fx, fy + 1, (float)data[(tmp = x * (yy + 1)) + xx] * hscale + bheight);
+                    *pv++ = aiVector3D(fx + 1, fy + 1, (float)data[tmp + xx + 1] * hscale + bheight);
+                    *pv++ = aiVector3D(fx + 1, fy, (float)data[tmp2 + xx + 1] * hscale + bheight);
+
+                    // also make texture coordinates, if necessary
+                    if (configComputeUVs) {
+                        *uv++ = aiVector3D(step_x * xx, step_y * yy, 0.f);
+                        *uv++ = aiVector3D(step_x * xx, step_y * (yy + 1), 0.f);
+                        *uv++ = aiVector3D(step_x * (xx + 1), step_y * (yy + 1), 0.f);
+                        *uv++ = aiVector3D(step_x * (xx + 1), step_y * yy, 0.f);
+                    }
+
+                    // make indices
+                    f->mIndices = new unsigned int[f->mNumIndices = 4];
+                    for (unsigned int i = 0; i < 4; ++i) {
+                        f->mIndices[i] = t;
+                        t++;
+                    }
+                }
+            }
+
+            // Add the mesh to the root node
+            root->mMeshes = new unsigned int[root->mNumMeshes = 1];
+            root->mMeshes[0] = 0;
+        }
+
+        // Get to the next chunk (4 byte aligned)
+        unsigned dtt = reader.GetCurrentPos();
+        if (dtt & 0x3) {
+            reader.IncPtr(4 - dtt);
+        }
+    }
+
+    // Check whether we have a mesh now
+    if (pScene->mNumMeshes != 1)
+        throw DeadlyImportError("TER: Unable to load terrain");
+
+    // Set the AI_SCENE_FLAGS_TERRAIN bit
+    pScene->mFlags |= AI_SCENE_FLAGS_TERRAIN;
+}
+
+#endif // !! ASSIMP_BUILD_NO_TERRAGEN_IMPORTER