/src/assimp/code/Material/MaterialSystem.cpp

Source
/*
Open Asset Import Library (assimp)
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*/

/** @file  MaterialSystem.cpp
 *  @brief Implementation of the material system of the library
 */

#include "MaterialSystem.h"
#include <assimp/Hash.h>
#include <assimp/ParsingUtils.h>
#include <assimp/fast_atof.h>
#include <assimp/material.h>
#include <assimp/types.h>
#include <assimp/DefaultLogger.hpp>
#include <memory>

using namespace Assimp;

// ------------------------------------------------------------------------------------------------
// Get a specific property from a material
aiReturn aiGetMaterialProperty(const aiMaterial *pMat,
        const char *pKey,
        unsigned int type,
        unsigned int index,
        const aiMaterialProperty **pPropOut) {
    ai_assert(pMat != nullptr);
    ai_assert(pKey != nullptr);
    ai_assert(pPropOut != nullptr);

    /*  Just search for a property with exactly this name ..
     *  could be improved by hashing, but it's possibly
     *  no worth the effort (we're bound to C structures,
     *  thus std::map or derivates are not applicable. */
    for (unsigned int i = 0; i < pMat->mNumProperties; ++i) {
        aiMaterialProperty *prop = pMat->mProperties[i];

        if (prop /* just for safety ... */
                && 0 == strncmp(prop->mKey.data, pKey, strlen(pKey)) && (UINT_MAX == type || prop->mSemantic == type) /* UINT_MAX is a wild-card, but this is undocumented :-) */
                && (UINT_MAX == index || prop->mIndex == index)) {
            *pPropOut = pMat->mProperties[i];
            return AI_SUCCESS;
        }
    }
    *pPropOut = nullptr;

    return AI_FAILURE;
}

namespace {

// ------------------------------------------------------------------------------------------------
// Implementation of functions "aiGetMaterialFloatArray" and "aiGetMaterialFloatFloatArray".
template <class TReal>
aiReturn GetMaterialFloatArray(const aiMaterial *pMat,
        const char *pKey,
        unsigned int type,
        unsigned int index,
        TReal *pOut,
        unsigned int *pMax) {
    ai_assert(pOut != nullptr);
    ai_assert(pMat != nullptr);

    const aiMaterialProperty *prop{nullptr};
    aiGetMaterialProperty(pMat, pKey, type, index, &prop);
    if (nullptr == prop) {
        return AI_FAILURE;
    }

    // data is given in floats, convert to TReal
    unsigned int iWrite = 0;
    if (aiPTI_Float == prop->mType || aiPTI_Buffer == prop->mType) {
        iWrite = prop->mDataLength / sizeof(float);
        if (pMax) {
            iWrite = std::min(*pMax, iWrite);
        }

        for (unsigned int a = 0; a < iWrite; ++a) {
            pOut[a] = static_cast<TReal>(reinterpret_cast<float *>(prop->mData)[a]);
        }

        if (pMax) {
            *pMax = iWrite;
        }
    } else if (aiPTI_Double == prop->mType) { // data is given in doubles, convert to TReal
        iWrite = prop->mDataLength / sizeof(double);
        if (pMax) {
            iWrite = std::min(*pMax, iWrite);
            ;
        }
        for (unsigned int a = 0; a < iWrite; ++a) {
            pOut[a] = static_cast<TReal>(reinterpret_cast<double *>(prop->mData)[a]);
        }
        if (pMax) {
            *pMax = iWrite;
        }
    } else if (aiPTI_Integer == prop->mType) { // data is given in ints, convert to TReal
        iWrite = prop->mDataLength / sizeof(int32_t);
        if (pMax) {
            iWrite = std::min(*pMax, iWrite);
            ;
        }
        for (unsigned int a = 0; a < iWrite; ++a) {
            pOut[a] = static_cast<TReal>(reinterpret_cast<int32_t *>(prop->mData)[a]);
        }
        if (pMax) {
            *pMax = iWrite;
        }
    } else { // a string ... read floats separated by spaces
        if (pMax) {
            iWrite = *pMax;
        }
        // strings are zero-terminated with a 32 bit length prefix, so this is safe
        const char *cur = prop->mData + 4;
        ai_assert(prop->mDataLength >= 5);
        ai_assert(!prop->mData[prop->mDataLength - 1]);
        for (unsigned int a = 0;; ++a) {
            cur = fast_atoreal_move(cur, pOut[a]);
            if (a == iWrite - 1) {
                break;
            }
            if (!IsSpace(*cur)) {
                ASSIMP_LOG_ERROR("Material property", pKey,
                                 " is a string; failed to parse a float array out of it.");
                return AI_FAILURE;
            }
        }

        if (pMax) {
            *pMax = iWrite;
        }
    }

    return AI_SUCCESS;
}

// ------------------------------------------------------------------------------------------------
// Get an array of float typed float values from the material.
aiReturn aiGetMaterialFloatFloatArray(const aiMaterial *pMat,
        const char *pKey,
        unsigned int type,
        unsigned int index,
        float *pOut,
        unsigned int *pMax) {
    return GetMaterialFloatArray(pMat, pKey, type, index, pOut, pMax);
}

} // namespace

// ------------------------------------------------------------------------------------------------
// Get an array of floating-point values from the material.
aiReturn aiGetMaterialFloatArray(const aiMaterial *pMat,
        const char *pKey,
        unsigned int type,
        unsigned int index,
        ai_real *pOut,
        unsigned int *pMax) {
    return GetMaterialFloatArray(pMat, pKey, type, index, pOut, pMax);
}

// ------------------------------------------------------------------------------------------------
// Get an array if integers from the material
aiReturn aiGetMaterialIntegerArray(const aiMaterial *pMat,
        const char *pKey,
        unsigned int type,
        unsigned int index,
        int *pOut,
        unsigned int *pMax) {
    ai_assert(pOut != nullptr);
    ai_assert(pMat != nullptr);

    const aiMaterialProperty *prop;
    aiGetMaterialProperty(pMat, pKey, type, index, &prop);
    if (!prop) {
        return AI_FAILURE;
    }

    // data is given in ints, simply copy it
    unsigned int iWrite = 0;
    if (aiPTI_Integer == prop->mType || aiPTI_Buffer == prop->mType) {
        iWrite = std::max(static_cast<unsigned int>(prop->mDataLength / sizeof(int32_t)), 1u);
        if (pMax) {
            iWrite = std::min(*pMax, iWrite);
        }
        if (1 == prop->mDataLength) {
            // bool type, 1 byte
            *pOut = static_cast<int>(*prop->mData);
        } else {
            for (unsigned int a = 0; a < iWrite; ++a) {
                pOut[a] = static_cast<int>(reinterpret_cast<int32_t *>(prop->mData)[a]);
            }
        }
        if (pMax) {
            *pMax = iWrite;
        }
    }
    // data is given in floats convert to int
    else if (aiPTI_Float == prop->mType) {
        iWrite = prop->mDataLength / sizeof(float);
        if (pMax) {
            iWrite = std::min(*pMax, iWrite);
            ;
        }
        for (unsigned int a = 0; a < iWrite; ++a) {
            pOut[a] = static_cast<int>(reinterpret_cast<float *>(prop->mData)[a]);
        }
        if (pMax) {
            *pMax = iWrite;
        }
    }
    // it is a string ... no way to read something out of this
    else {
        if (pMax) {
            iWrite = *pMax;
        }
        // strings are zero-terminated with a 32 bit length prefix, so this is safe
        const char *cur = prop->mData + 4;
        ai_assert(prop->mDataLength >= 5);
        ai_assert(!prop->mData[prop->mDataLength - 1]);
        for (unsigned int a = 0;; ++a) {
            pOut[a] = strtol10(cur, &cur);
            if (a == iWrite - 1) {
                break;
            }
            if (!IsSpace(*cur)) {
                ASSIMP_LOG_ERROR("Material property", pKey,
                                 " is a string; failed to parse an integer array out of it.");
                return AI_FAILURE;
            }
        }

        if (pMax) {
            *pMax = iWrite;
        }
    }
    return AI_SUCCESS;
}

// ------------------------------------------------------------------------------------------------
// Get a color (3 or 4 floats) from the material
aiReturn aiGetMaterialColor(const aiMaterial *pMat,
        const char *pKey,
        unsigned int type,
        unsigned int index,
        aiColor4D *pOut) {
    unsigned int iMax = 4;
    const aiReturn eRet = aiGetMaterialFloatFloatArray(pMat, pKey, type, index, (float *)pOut, &iMax);

    // if no alpha channel is defined: set it to 1.0
    if (3 == iMax) {
        pOut->a = 1.0;
    }

    return eRet;
}

// ------------------------------------------------------------------------------------------------
// Get a aiUVTransform (5 floats) from the material
aiReturn aiGetMaterialUVTransform(const aiMaterial *pMat,
        const char *pKey,
        unsigned int type,
        unsigned int index,
        aiUVTransform *pOut) {
    unsigned int iMax = 5;
    return aiGetMaterialFloatArray(pMat, pKey, type, index, reinterpret_cast<ai_real *>(pOut), &iMax);
}

// ------------------------------------------------------------------------------------------------
// Get a string from the material
aiReturn aiGetMaterialString(const aiMaterial *pMat,
        const char *pKey,
        unsigned int type,
        unsigned int index,
        aiString *pOut) {
    ai_assert(pOut != nullptr);

    const aiMaterialProperty *prop{nullptr};
    aiGetMaterialProperty(pMat, pKey, type, index, &prop);
    if (!prop) {
        return AI_FAILURE;
    }

    if (aiPTI_String == prop->mType) {
        ai_assert(prop->mDataLength >= 5);

        // The string is stored as 32 but length prefix followed by zero-terminated UTF8 data
        pOut->length = static_cast<unsigned int>(*reinterpret_cast<uint32_t *>(prop->mData));

        ai_assert(pOut->length + 1 + 4 == prop->mDataLength);
        ai_assert(!prop->mData[prop->mDataLength - 1]);
        memcpy(pOut->data, prop->mData + 4, pOut->length + 1);
    } else {
        // TODO - implement lexical cast as well
        ASSIMP_LOG_ERROR("Material property", pKey, " was found, but is no string");
        return AI_FAILURE;
    }
    return AI_SUCCESS;
}

// ------------------------------------------------------------------------------------------------
// Get a c-like string fron an aiString
const char *aiGetStringC_Str(const aiString *str) {
  return str->data;
}

// ------------------------------------------------------------------------------------------------
// Get the number of textures on a particular texture stack
unsigned int aiGetMaterialTextureCount(const C_STRUCT aiMaterial *pMat, C_ENUM aiTextureType type) {
    ai_assert(pMat != nullptr);

    // Textures are always stored with ascending indices (ValidateDS provides a check, so we don't need to do it again)
    unsigned int max = 0;
    for (unsigned int i = 0; i < pMat->mNumProperties; ++i) {
        aiMaterialProperty *prop = pMat->mProperties[i];

        if (prop /* just a sanity check ... */
                && 0 == strcmp(prop->mKey.data, _AI_MATKEY_TEXTURE_BASE) && static_cast<aiTextureType>(prop->mSemantic) == type) {

            max = std::max(max, prop->mIndex + 1);
        }
    }
    return max;
}

// ------------------------------------------------------------------------------------------------
aiReturn aiGetMaterialTexture(const C_STRUCT aiMaterial *mat,
        aiTextureType type,
        unsigned int index,
        C_STRUCT aiString *path,
        aiTextureMapping *_mapping /*= nullptr*/,
        unsigned int *uvindex /*= nullptr*/,
        ai_real *blend /*= nullptr*/,
        aiTextureOp *op /*= nullptr*/,
        aiTextureMapMode *mapmode /*= nullptr*/,
        unsigned int *flags /*= nullptr*/
) {
    ai_assert(nullptr != mat);
    ai_assert(nullptr != path);

    // Get the path to the texture
    if (AI_SUCCESS != aiGetMaterialString(mat, AI_MATKEY_TEXTURE(type, index), path)) {
        return AI_FAILURE;
    }

    // Determine mapping type
    int mapping_ = aiTextureMapping_UV;
    aiGetMaterialInteger(mat, AI_MATKEY_MAPPING(type, index), &mapping_);
    aiTextureMapping mapping = static_cast<aiTextureMapping>(mapping_);
    if (_mapping)
        *_mapping = mapping;

    // Get UV index
    if (aiTextureMapping_UV == mapping && uvindex) {
        aiGetMaterialInteger(mat, AI_MATKEY_UVWSRC(type, index), (int *)uvindex);
    }
    // Get blend factor
    if (blend) {
        aiGetMaterialFloat(mat, AI_MATKEY_TEXBLEND(type, index), blend);
    }
    // Get texture operation
    if (op) {
        aiGetMaterialInteger(mat, AI_MATKEY_TEXOP(type, index), (int *)op);
    }
    // Get texture mapping modes
    if (mapmode) {
        aiGetMaterialInteger(mat, AI_MATKEY_MAPPINGMODE_U(type, index), (int *)&mapmode[0]);
        aiGetMaterialInteger(mat, AI_MATKEY_MAPPINGMODE_V(type, index), (int *)&mapmode[1]);
    }
    // Get texture flags
    if (flags) {
        aiGetMaterialInteger(mat, AI_MATKEY_TEXFLAGS(type, index), (int *)flags);
    }

    return AI_SUCCESS;
}

static constexpr unsigned int DefaultNumAllocated = 5;

// ------------------------------------------------------------------------------------------------
// Construction. Actually the one and only way to get an aiMaterial instance
aiMaterial::aiMaterial() : mProperties(nullptr), mNumProperties(0), mNumAllocated(DefaultNumAllocated) {
    // Allocate 5 entries by default
    mProperties = new aiMaterialProperty *[DefaultNumAllocated];
}

// ------------------------------------------------------------------------------------------------
aiMaterial::~aiMaterial() {
    Clear();

    delete[] mProperties;
}

// ------------------------------------------------------------------------------------------------
aiString aiMaterial::GetName() const {
    aiString name{};
    Get(AI_MATKEY_NAME, name);

    return name;
}

// ------------------------------------------------------------------------------------------------
void aiMaterial::Clear() {
    for (unsigned int i = 0; i < mNumProperties; ++i) {
        // delete this entry
        delete mProperties[i];
        AI_DEBUG_INVALIDATE_PTR(mProperties[i]);
    }
    mNumProperties = 0;

    // The array remains allocated, we just invalidated its contents
}

// ------------------------------------------------------------------------------------------------
aiReturn aiMaterial::RemoveProperty(const char *pKey, unsigned int type, unsigned int index) {
    ai_assert(nullptr != pKey);

    for (unsigned int i = 0; i < mNumProperties; ++i) {
        aiMaterialProperty *prop = mProperties[i];

        if (prop && !strcmp(prop->mKey.data, pKey) &&
                prop->mSemantic == type && prop->mIndex == index) {
            // Delete this entry
            delete mProperties[i];

            // collapse the array behind --.
            --mNumProperties;
            for (unsigned int a = i; a < mNumProperties; ++a) {
                mProperties[a] = mProperties[a + 1];
            }
            return AI_SUCCESS;
        }
    }

    return AI_FAILURE;
}

// ------------------------------------------------------------------------------------------------
aiReturn aiMaterial::AddBinaryProperty(const void *pInput,
        unsigned int pSizeInBytes,
        const char *pKey,
        unsigned int type,
        unsigned int index,
        aiPropertyTypeInfo pType) {
    ai_assert(pInput != nullptr);
    ai_assert(pKey != nullptr);
    ai_assert(0 != pSizeInBytes);

    if (0 == pSizeInBytes) {
        return AI_FAILURE;
    }

    // first search the list whether there is already an entry with this key
    unsigned int iOutIndex(UINT_MAX);
    for (unsigned int i = 0; i < mNumProperties; ++i) {
        aiMaterialProperty *prop(mProperties[i]);

        if (prop /* just for safety */ && !strcmp(prop->mKey.data, pKey) &&
                prop->mSemantic == type && prop->mIndex == index) {

            delete mProperties[i];
            iOutIndex = i;
        }
    }

    // Allocate a new material property
    auto pcNew = std::make_unique<aiMaterialProperty>();

    // .. and fill it
    pcNew->mType = pType;
    pcNew->mSemantic = type;
    pcNew->mIndex = index;

    pcNew->mDataLength = pSizeInBytes;
    pcNew->mData = new char[pSizeInBytes];
    memcpy(pcNew->mData, pInput, pSizeInBytes);

    const size_t keyLen = ::strlen(pKey);
    pcNew->mKey.length = static_cast<ai_uint32>(std::min<size_t>(keyLen, AI_MAXLEN - 1));
    if (keyLen >= AI_MAXLEN) {
        ASSIMP_LOG_WARN("aiMaterial: property key '", pKey, "' exceeds AI_MAXLEN and will be truncated.");
    }
  memcpy(pcNew->mKey.data, pKey, pcNew->mKey.length);
    pcNew->mKey.data[pcNew->mKey.length] = '\0';

    if (UINT_MAX != iOutIndex) {
        mProperties[iOutIndex] = pcNew.release();
        return AI_SUCCESS;
    }

    // resize the array ... double the storage allocated
    if (mNumProperties == mNumAllocated) {
        const unsigned int iOld = mNumAllocated;
        mNumAllocated *= 2;

        aiMaterialProperty **ppTemp;
        try {
            ppTemp = new aiMaterialProperty *[mNumAllocated];
        } catch (std::bad_alloc &) {
            return AI_OUTOFMEMORY;
        }

        // just copy all items over; then replace the old array
        memcpy(ppTemp, mProperties, iOld * sizeof(void *));

        delete[] mProperties;
        mProperties = ppTemp;
    }
    // push back ...
    mProperties[mNumProperties++] = pcNew.release();

    return AI_SUCCESS;
}

// ------------------------------------------------------------------------------------------------
aiReturn aiMaterial::AddProperty(const aiString *pInput,
        const char *pKey,
        unsigned int type,
        unsigned int index) {
    ai_assert(sizeof(ai_uint32) == 4);
    return AddBinaryProperty(pInput,
            static_cast<unsigned int>(pInput->length + 1 + 4),
            pKey,
            type,
            index,
            aiPTI_String);
}

// ------------------------------------------------------------------------------------------------
uint32_t Assimp::ComputeMaterialHash(const aiMaterial *mat, bool includeMatName /*= false*/) {
    uint32_t hash = 1503; // magic start value, chosen to be my birthday :-)
    for (unsigned int i = 0; i < mat->mNumProperties; ++i) {
        // Exclude all properties whose first character is '?' from the hash
        // See doc for aiMaterialProperty.
        const aiMaterialProperty *prop = mat->mProperties[i];
        if (nullptr != prop && (includeMatName || prop->mKey.data[0] != '?')) {

            hash = SuperFastHash(prop->mKey.data, (unsigned int)prop->mKey.length, hash);
            hash = SuperFastHash(prop->mData, prop->mDataLength, hash);

            // Combine the semantic and the index with the hash
            hash = SuperFastHash((const char *)&prop->mSemantic, sizeof(unsigned int), hash);
            hash = SuperFastHash((const char *)&prop->mIndex, sizeof(unsigned int), hash);
        }
    }
    return hash;
}

// ------------------------------------------------------------------------------------------------
void aiMaterial::CopyPropertyList(aiMaterial *const pcDest,
        const aiMaterial *pcSrc) {
    ai_assert(nullptr != pcDest);
    ai_assert(nullptr != pcSrc);
    ai_assert(pcDest->mNumProperties <= pcDest->mNumAllocated);
    ai_assert(pcSrc->mNumProperties <= pcSrc->mNumAllocated);

    const unsigned int iOldNum = pcDest->mNumProperties;
    pcDest->mNumAllocated += pcSrc->mNumAllocated;
    pcDest->mNumProperties += pcSrc->mNumProperties;

    const unsigned int numAllocated = pcDest->mNumAllocated;
    aiMaterialProperty **pcOld = pcDest->mProperties;
    pcDest->mProperties = new aiMaterialProperty *[numAllocated];

    ai_assert(!iOldNum || pcOld);
    ai_assert(iOldNum < numAllocated);

    if (iOldNum && pcOld) {
        for (unsigned int i = 0; i < iOldNum; ++i) {
            pcDest->mProperties[i] = pcOld[i];
        }
    }

    if (pcOld) {
        delete[] pcOld;
    }

    for (unsigned int i = iOldNum; i < pcDest->mNumProperties; ++i) {
        const aiMaterialProperty *propSrc = pcSrc->mProperties[i];

        // search whether we have already a property with this name -> if yes, overwrite it
        aiMaterialProperty *prop;
        for (unsigned int q = 0; q < iOldNum; ++q) {
            prop = pcDest->mProperties[q];
            if (prop /* just for safety */ && prop->mKey == propSrc->mKey && prop->mSemantic == propSrc->mSemantic && prop->mIndex == propSrc->mIndex) {
                delete prop;

                // collapse the whole array ...
                memmove(&pcDest->mProperties[q], &pcDest->mProperties[q + 1], i - q);
                i--;
                pcDest->mNumProperties--;
            }
        }

        // Allocate the output property and copy the source property
        prop = pcDest->mProperties[i] = new aiMaterialProperty();
        prop->mKey = propSrc->mKey;
        prop->mDataLength = propSrc->mDataLength;
        prop->mType = propSrc->mType;
        prop->mSemantic = propSrc->mSemantic;
        prop->mIndex = propSrc->mIndex;

        prop->mData = new char[propSrc->mDataLength];
        memcpy(prop->mData, propSrc->mData, prop->mDataLength);
    }
}

Coverage Report

Created: 2026-05-23 06:04