78 lines
3.6 KiB
ReStructuredText
78 lines
3.6 KiB
ReStructuredText
Asset Management
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===================================================================================================
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On Disk (file) Layout
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---------------------------------------------------------------------------------------------------
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.. code-block:: md
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{version} | 4 bytes, ie. uint32_t
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{general metadata} | sizeof(AssetMetadata)
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{specialized metadata} | sizeof(XXXAssetMetadata), eg. TextureAssetMetadata
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{n} | 4 bytes, ie. uint32_t
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{blob_0...n metadata} | n * sizeof(BlobMetadata)
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{blob_0...n data} | variable size based on actual data
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{end marker} | 8 byte, ie size_t for marking the END
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Sections
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---------------------------------------------------------------------------------------------------
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.. code-block:: md
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version -> The version of the asset for forward compatibility
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general metadata -> Common asset metadata such as file-path, asset-type, creator, etc.
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specialized metadata -> Metadata specific to the asset, eg. texture dimensions for Textures.
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n -> The number of blobs.
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blob_0...n metadata -> Metadata specifying how the actual data is packed, required for unpacking.
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blob_0...n data -> The actual data, packed and compressed to be reacdy for direct engine consumption.
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Loading
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---------------------------------------------------------------------------------------------------
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TESTING TESTING
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TESTING TESTING
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TESTING TESTING
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TESTING TESTING
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Loading pre-baked asset files (like .png files) for baking:
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Each **Loader** has ONE OR MORE supported input file types (detected via the file extension): eg. StbLoader -> Can read in .jpg, .png, .bmp, etc.... files
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Each **Loader** has ONLY ONE supported output asset type:
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eg. StbLoader -> outputs TextureAsset
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Multiple **Loader**\s MAY have as output the same asset type:
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eg. StbLoader -> outputs TextureAsset
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eg. SomeOtherImgLoader -> outputs TextureAsset
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Multiple **Loader**\s SHOULD NOT have as input same extension types
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eg. .jpg, .png -> if supported, should only be supported by 1 **Loader** class
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Each **Loader** SHOULD read and turn the data from a file (eg. .png for textures) into something
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understandable by a **Packer** (not the engine itself).
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A **Loader** SHOULD NOT be responsible for packing the parsed file data into asset data,
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as that implies direct understanding of the layout required by the engine.
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And if that layout changes, ALL **Loader**s should change accordingly;
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which makes a class that's responsible for reading files dependant on the engine's (potentially frequent) internal changes.
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The logic is to reduce many-to-one dependency into a one-to-one dependency by redirecting the packing process to **Packer** classes
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Packing
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---------------------------------------------------------------------------------------------------
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Each **Packer** is responsible for packing ONLY ONE asset type:
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eg. TexturePacker for packing texture assets from parsed image files.
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eg. ModelPacker for packing model assets from parsed model files.
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Each **Packer** will output ONE OR MORE blobs of data,
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and for EACH blob of data, it'll write a BlobMetadata, AFTER the specialized metadata (eg. TextureAssetMetadata)
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A **Packer** will make use of the **Compressor** classes to compress the data,
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and lay it out in a way that is suitable for the engine's consumption.
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Unpacking
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---------------------------------------------------------------------------------------------------
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A **Parser** is responsible for parsing ONLY ONE asset type:
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eg. TextureParser for parsing texture assets for direct engine consumption.
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eg. ModelParser for parsing model assets for direct engine consumption.
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