hw impl of ipf codec (encoding not tested)

assets/disk0/decodeipf.js

@@ -153,8 +153,8 @@ function ycocgToRGB(co, cg, ys, as) { // ys: 4 Y-values
 //    cocg = 0x7777
 //    ys = 0x7777
 
-    co = (co - 7) / 8
-    cg = (cg - 7) / 8
+    co = (co - 7) / 8.0
+    cg = (cg - 7) / 8.0
 
     let y1 = (ys & 15) / 15.0
     let a1 = as & 15

assets/disk0/dipf.js

@@ -0,0 +1,162 @@
+if (!exec_args[1]) {
+    printerrln("Usage: decodeipf input.ipf")
+    return 1
+}
+
+let filename = exec_args[1]
+
+const MAGIC = [0x1F, 0x54, 0x53, 0x56, 0x4D, 0x69, 0x50, 0x46]
+const port = filesystem._toPorts("A")[0]
+
+
+com.sendMessage(port, "DEVRST\x17")
+com.sendMessage(port, `OPENR"${filename}",1`)
+let statusCode = com.getStatusCode(port)
+
+if (statusCode != 0) {
+    printerrln(`No such file (${statusCode})`)
+    return statusCode
+}
+
+com.sendMessage(port, "READ")
+statusCode = com.getStatusCode(port)
+if (statusCode != 0) {
+    printerrln("READ failed with "+statusCode)
+    return statusCode
+}
+
+con.clear(); con.curs_set(0)
+
+let readCount = 0
+
+function readBytes(length) {
+    let ptr = sys.malloc(length)
+    let requiredBlocks = Math.floor((readCount + length) / 4096) - Math.floor(readCount / 4096)
+
+    let completedReads = 0
+
+    //serial.println(`readBytes(${length}); readCount = ${readCount}`)
+
+    for (let bc = 0; bc < requiredBlocks + 1; bc++) {
+        if (completedReads >= length) break
+
+        if (readCount % 4096 == 0) {
+            //serial.println("READ from serial")
+            // pull the actual message
+            sys.poke(-4093 - port, 6);sys.sleep(0) // spinning is required as Graal run is desynced with the Java side
+
+            let blockTransferStatus = ((sys.peek(-4085 - port*2) & 255) | ((sys.peek(-4086 - port*2) & 255) << 8))
+            let thisBlockLen = blockTransferStatus & 4095
+            if (thisBlockLen == 0) thisBlockLen = 4096 // [1, 4096]
+            let hasMore = (blockTransferStatus & 0x8000 != 0)
+
+
+            //serial.println(`block: (${thisBlockLen})[${[...Array(thisBlockLen).keys()].map(k => (sys.peek(-4097 - k) & 255).toString(16).padStart(2,'0')).join()}]`)
+
+            let remaining = Math.min(thisBlockLen, length - completedReads)
+
+            //serial.println(`Pulled a block (${thisBlockLen}); readCount = ${readCount}, completedReads = ${completedReads}, remaining = ${remaining}`)
+
+            // copy from read buffer to designated position
+            sys.memcpy(-4097, ptr + completedReads, remaining)
+
+            // increment readCount properly
+            readCount += remaining
+            completedReads += remaining
+        }
+        else {
+            let padding = readCount % 4096
+            let remaining = length - completedReads
+            let thisBlockLen = Math.min(4096 - padding, length - completedReads)
+
+            //serial.println(`padding = ${padding}; remaining = ${remaining}`)
+
+            //serial.println(`block: (${thisBlockLen})[${[...Array(thisBlockLen).keys()].map(k => (sys.peek(-4097 - padding - k) & 255).toString(16).padStart(2,'0')).join()}]`)
+
+            //serial.println(`Reusing a block (${thisBlockLen}); readCount = ${readCount}, completedReads = ${completedReads}`)
+
+            // copy from read buffer to designated position
+            sys.memcpy(-4097 - padding, ptr + completedReads, thisBlockLen)
+
+            // increment readCount properly
+            readCount += thisBlockLen
+            completedReads += thisBlockLen
+        }
+    }
+
+    //serial.println(`END readBytes(${length}); readCount = ${readCount}\n`)
+
+    return ptr
+}
+
+function readInt() {
+    let b = readBytes(4)
+    let i = (sys.peek(b) & 255) | ((sys.peek(b+1) & 255) << 8) | ((sys.peek(b+2) & 255) << 16) | ((sys.peek(b+3) & 255) << 24)
+
+    //serial.println(`readInt(); bytes: ${sys.peek(b)}, ${sys.peek(b+1)}, ${sys.peek(b+2)}, ${sys.peek(b+3)} = ${i}\n`)
+
+    sys.free(b)
+    return i
+}
+
+function readShort() {
+    let b = readBytes(2)
+    let i = (sys.peek(b) & 255) | ((sys.peek(b+1) & 255) << 8)
+
+    //serial.println(`readShort(); bytes: ${sys.peek(b)}, ${sys.peek(b+1)} = ${i}\n`)
+
+    sys.free(b)
+    return i
+}
+
+function readByte() {
+    let b = readBytes(1)
+    let i = (sys.peek(b) & 255)
+
+    //serial.println(`readShort(); bytes: ${sys.peek(b)}, ${sys.peek(b+1)} = ${i}\n`)
+
+    sys.free(b)
+    return i
+}
+
+
+let magic = readBytes(8)
+let magicMatching = true
+
+// check if magic number matches
+MAGIC.forEach((b,i) => {
+    let testb = sys.peek(magic + i) & 255 // for some reason this must be located here
+    if (testb != b) {
+        magicMatching = false
+    }
+})
+sys.free(magic)
+if (!magicMatching) {
+    println("Not an IPF file (MAGIC mismatch)")
+    return 1
+}
+
+let imgw = readShort()
+let imgh = readShort()
+let hasAlpha = (readShort() != 0)
+let ipfType = readByte()
+sys.free(readBytes(9)) // skip 10 bytes
+
+graphics.setGraphicsMode(4)
+
+let infile =
+    (0 == ipfType) ? readBytes((imgw * imgh / 16) * ((hasAlpha) ? 20 : 12)) :
+    (3 == ipfType) ? readBytes((imgw * imgh / 16) * ((hasAlpha) ? 24 : 16)) : null
+
+if (null == infile) {
+    printerrln("Unsupported IPF configuration: "+ipfType)
+    sys.free(infile)
+    return 1
+}
+
+if (0 == ipfType)
+    graphics.decodeIpf1(infile, -1048577, -1310721, imgw, imgh, hasAlpha)
+else if (3 == ipfType)
+    graphics.decodeIpf2(infile, -1048577, -1310721, imgw, imgh, hasAlpha)
+
+sys.free(infile)