Resources (WIP)

raylib/rres.go

@@ -0,0 +1,210 @@
+package raylib
+
+import (
+	"bytes"
+	"compress/flate"
+	"encoding/binary"
+	"fmt"
+	"os"
+	"unsafe"
+)
+
+// rRES file header (8 byte)
+type RRESFileHeader struct {
+	// File identifier: rRES (4 byte)
+	Id [4]int8
+	// File version and subversion (2 byte)
+	Version uint16
+	// Number of resources in this file (2 byte)
+	Count uint16
+}
+
+// rRES info header, every resource includes this header (16 byte + 16 byte)
+type RRESInfoHeader struct {
+	// Resource unique identifier (4 byte)
+	Id uint32
+	// Resource data type (1 byte)
+	DataType uint8
+	// Resource data compression type (1 byte)
+	CompType uint8
+	// Resource data encryption type (1 byte)
+	CryptoType uint8
+	// Resource data parts count, used for splitted data (1 byte)
+	PartsCount uint8
+	// Resource data size (compressed or not, only DATA) (4 byte)
+	DataSize uint32
+	// Resource data size (uncompressed, only DATA) (4 byte)
+	UncompSize uint32
+	// Resouce parameter 1 (4 byte)
+	Param1 uint32
+	// Resouce parameter 2 (4 byte)
+	Param2 uint32
+	// Resouce parameter 3 (4 byte)
+	Param3 uint32
+	// Resouce parameter 4 (4 byte)
+	Param4 uint32
+}
+
+// rRES data types
+const (
+	RRESTypeRaw = iota
+	RRESTypeImage
+	RRESTypeWave
+	RRESTypeVertex
+	RRESTypeText
+	RRESTypeFontImage
+	RRESTypeFontData
+	RRESTypeDirectory
+)
+
+// Compression types
+const (
+	// No data compression
+	RRESCompNone = iota
+	// DEFLATE compression
+	RRESCompDeflate
+	// LZ4 compression
+	RRESCompLz4
+	// LZMA compression
+	RRESCompLzma
+	// BROTLI compression
+	RRESCompBrotli
+)
+
+const (
+	// 8 bit per pixel (no alpha)
+	RRESImUncompGrayscale = iota + 1
+	// 16 bpp (2 channels)
+	RRESImUncompGrayAlpha
+	// 16 bpp
+	RRESImUncompR5g6b5
+	// 24 bpp
+	RRESImUncompR8g8b8
+	// 16 bpp (1 bit alpha)
+	RRESImUncompR5g5b5a1
+	// 16 bpp (4 bit alpha)
+	RRESImUncompR4g4b4a4
+	// 32 bpp
+	RRESImUncompR8g8b8a8
+	// 4 bpp (no alpha)
+	RRESImCompDxt1Rgb
+	// 4 bpp (1 bit alpha)
+	RRESImCompDxt1Rgba
+	// 8 bpp
+	RRESImCompDxt3Rgba
+	// 8 bpp
+	RRESImCompDxt5Rgba
+	// 4 bpp
+	RRESImCompEtc1Rgb
+	// 4 bpp
+	RRESImCompEtc2Rgb
+	// 8 bpp
+	RRESImCompEtc2EacRgba
+	// 4 bpp
+	RRESImCompPvrtRgb
+	// 4 bpp
+	RRESImCompPvrtRgba
+	// 8 bpp
+	RRESImCompAstc4x4Rgba
+	// 2 bpp
+	RRESImCompAstc8x8Rgba
+)
+
+const (
+	RRESVertPosition = iota
+	RRESVertTexcoord1
+	RRESVertTexcoord2
+	RRESVertTexcoord3
+	RRESVertTexcoord4
+	RRESVertNormal
+	RRESVertTangent
+	RRESVertColor
+	RRESVertIndex
+)
+
+const (
+	RRESVertByte = iota
+	RRESVertShort
+	RRESVertInt
+	RRESVertHfloat
+	RRESVertFloat
+)
+
+// Load resource from file (only one)
+// NOTE: Returns uncompressed data with parameters, only first resource found
+func LoadResource(fileName string) []byte {
+	return LoadResourceById(fileName, 0)
+}
+
+// Load resource from file by id
+// NOTE: Returns uncompressed data with parameters, search resource by id
+func LoadResourceById(fileName string, rresId int) (data []byte) {
+	file, err := os.Open(fileName)
+	if err != nil {
+		TraceLog(LogWarning, "[%s] rRES raylib resource file could not be opened", fileName)
+		return
+	}
+	defer file.Close()
+
+	fileHeader := RRESFileHeader{}
+	infoHeader := RRESInfoHeader{}
+
+	// Read rres file header
+	err = binary.Read(file, binary.LittleEndian, &fileHeader)
+	if err != nil {
+		TraceLog(LogWarning, err.Error())
+		return
+	}
+
+	//fmt.Printf("%+v\n", fileHeader)
+
+	// Verify "rRES" identifier
+	id := fmt.Sprintf("%c", fileHeader.Id)
+	if id != "[r R E S]" {
+		TraceLog(LogWarning, "[%s] This is not a valid raylib resource file", fileName)
+		return
+	}
+
+	file.Seek(int64(unsafe.Sizeof(fileHeader)), os.SEEK_CUR)
+
+	for i := 0; i < int(fileHeader.Count); i++ {
+		// Read resource info and parameters
+		err = binary.Read(file, binary.LittleEndian, &infoHeader)
+		if err != nil {
+			TraceLog(LogWarning, err.Error())
+			return
+		}
+
+		//fmt.Printf("%+v\n", infoHeader)
+
+		file.Seek(int64(unsafe.Sizeof(infoHeader)), os.SEEK_CUR)
+
+		if int(infoHeader.Id) == rresId {
+			// Read resource data block
+			data = make([]byte, infoHeader.DataSize)
+			file.Read(data)
+
+			if infoHeader.CompType == RRESCompDeflate {
+				// Uncompress data
+				b := bytes.NewReader(data)
+				r := flate.NewReader(b)
+
+				data = make([]byte, infoHeader.UncompSize)
+				r.Read(data)
+			}
+
+			if len(data) > 0 {
+				TraceLog(LogInfo, "[%s][ID %d] Resource data loaded successfully", fileName, infoHeader.Id)
+			}
+		} else {
+			// Skip required data to read next resource infoHeader
+			file.Seek(int64(infoHeader.DataSize), os.SEEK_CUR)
+		}
+	}
+
+	if len(data) == 0 {
+		TraceLog(LogInfo, "[%s][ID %d] Requested resource could not be found", fileName, rresId)
+	}
+
+	return
+}