SuperHiRes video mode

cardVidHD.go

@@ -5,6 +5,7 @@ Simulates just what is needed to make Total Replay use the GS modes if the VidHD
 
 See:
 	https://github.com/a2-4am/4cade/blob/master/src/hw.vidhd.a
+	http://www.applelogic.org/files/GSHARDWAREREF.pdf, page 89
 */
 
 type cardVidHD struct {
@@ -21,6 +22,20 @@ func buildVidHDRom() []uint8 {
 	return data
 }
 
+const (
+	ioDataNewVideo uint8 = 0x29
+)
+
 func (c *cardVidHD) assign(a *Apple2, slot int) {
+	// The softswitches are outside the card reverded ss
+	a.io.addSoftSwitchR(0x22, notImplementedSoftSwitchR, "VIDHD-TBCOLOR")
+	a.io.addSoftSwitchW(0x22, notImplementedSoftSwitchW, "VIDHD-TBCOLOR")
+	a.io.addSoftSwitchR(0x29, getStatusSoftSwitch(ioDataNewVideo), "VIDHD-NEWVIDEO")
+	a.io.addSoftSwitchW(0x29, setStatusSoftSwitch(ioDataNewVideo), "VIDHD-NEWVIDEO")
+	a.io.addSoftSwitchR(0x34, notImplementedSoftSwitchR, "VIDHD-CLOCKCTL")
+	a.io.addSoftSwitchW(0x34, notImplementedSoftSwitchW, "VIDHD-CLOCKCTL")
+	a.io.addSoftSwitchR(0x35, notImplementedSoftSwitchR, "VIDHD-SHADOW")
+	a.io.addSoftSwitchW(0x35, notImplementedSoftSwitchW, "VIDHD-SHADOW")
+
 	c.cardBase.assign(a, slot)
 }

screen.go

@@ -24,6 +24,7 @@ func Snapshot(a *Apple2) *image.RGBA {
 	is80Columns := a.io.isSoftSwitchActive(ioFlag80Col)
 	isDoubleResMode := !isTextMode && is80Columns && !a.io.isSoftSwitchActive(ioFlagAnnunciator3)
 	isSecondPage := a.io.isSoftSwitchActive(ioFlagSecondPage) && !a.mmu.store80Active
+	isSuperHighResMode := a.io.isSoftSwitchActive(ioDataNewVideo)
 
 	var lightColor color.Color
 	if isColor {
@@ -36,7 +37,9 @@ func Snapshot(a *Apple2) *image.RGBA {
 	}
 
 	var snap *image.RGBA
-	if isTextMode {
+	if isSuperHighResMode { // Has to be first and disables the rest
+		snap = snapshotSuperHiResMode(a)
+	} else if isTextMode {
 		snap = snapshotTextMode(a, is80Columns, isSecondPage, false /*isMixMode*/, lightColor)
 	} else {
 		if isHiResMode {
@@ -58,7 +61,9 @@ func Snapshot(a *Apple2) *image.RGBA {
 		}
 	}
 
-	snap = linesSeparatedFilter(snap)
+	if !isSuperHighResMode {
+		snap = linesSeparatedFilter(snap)
+	}
 	return snap
 }
 

screenDoubleHiRes.go

@@ -0,0 +1,47 @@
+package apple2
+
+import (
+	"image"
+	"image/color"
+)
+
+const (
+	doubleHiResWidth = 2 * hiResWidth
+)
+
+func snapshotDoubleHiResModeMono(a *Apple2, isSecondPage bool, mixedMode bool, light color.Color) *image.RGBA {
+	// As described in "Inside the Apple IIe"
+
+	height := hiResHeight
+	if mixedMode {
+		height = hiResHeightMixed
+	}
+
+	size := image.Rect(0, 0, doubleHiResWidth, height)
+	img := image.NewRGBA(size)
+	for y := 0; y < height; y++ {
+		lineParts := [][]uint8{
+			getHiResLine(a, y, isSecondPage, true),
+			getHiResLine(a, y, isSecondPage, false),
+		}
+		x := 0
+		// For the NTSC filter to work we have to insert an initial black pixel and skip the last one
+		img.Set(x, y, color.Black)
+		x++
+		for iByte := 0; iByte < hiResLineBytes-1; iByte++ {
+			for iPart := 0; iPart < 2; iPart++ {
+				b := lineParts[iPart][iByte]
+				for j := uint(0); j < 7; j++ {
+					bit := (b >> j) & 1
+					colour := light
+					if bit == 0 {
+						colour = color.Black
+					}
+					img.Set(x, y, colour)
+					x++
+				}
+			}
+		}
+	}
+	return img
+}

screenHiRes.go

@@ -8,7 +8,6 @@ import (
 const (
 	hiResWidth        = 280
 	hiResLineBytes    = hiResWidth / 7
-	doubleHiResWidth  = 2 * hiResWidth
 	hiResHeight       = 192
 	hiResHeightMixed  = 160
 	hiResPage1Address = uint16(0x2000)
@@ -72,40 +71,3 @@ func snapshotHiResModeMono(a *Apple2, isSecondPage bool, mixedMode bool, light c
 	}
 	return img
 }
-
-func snapshotDoubleHiResModeMono(a *Apple2, isSecondPage bool, mixedMode bool, light color.Color) *image.RGBA {
-	// As described in "Inside the Apple IIe"
-
-	height := hiResHeight
-	if mixedMode {
-		height = hiResHeightMixed
-	}
-
-	size := image.Rect(0, 0, doubleHiResWidth, height)
-	img := image.NewRGBA(size)
-	for y := 0; y < height; y++ {
-		lineParts := [][]uint8{
-			getHiResLine(a, y, isSecondPage, true),
-			getHiResLine(a, y, isSecondPage, false),
-		}
-		x := 0
-		// For the NTSC filter to work we have to insert an initial black pixel and skip the last one
-		img.Set(x, y, color.Black)
-		x++
-		for iByte := 0; iByte < hiResLineBytes-1; iByte++ {
-			for iPart := 0; iPart < 2; iPart++ {
-				b := lineParts[iPart][iByte]
-				for j := uint(0); j < 7; j++ {
-					bit := (b >> j) & 1
-					colour := light
-					if bit == 0 {
-						colour = color.Black
-					}
-					img.Set(x, y, colour)
-					x++
-				}
-			}
-		}
-	}
-	return img
-}

screenSuperHiRes.go

@@ -0,0 +1,97 @@
+package apple2
+
+import (
+	"image"
+	"image/color"
+)
+
+const (
+	shrWidth      = 640
+	shrWidthBytes = 640 / 4
+	shrHeight     = 200
+	palettesCount = 256
+
+	shrPixelDataAddress        = uint16(0x2000)
+	shrScanLineControlAddress  = uint16(0x9d00)
+	shrColorPalettesAddress    = uint16(0x9e00)
+	shrColorPalettesAddressEnd = uint16(0xa000)
+)
+
+func snapshotSuperHiResMode(a *Apple2) *image.RGBA {
+	// See "Apple IIGS Hardware Reference", chapter 4, page 91
+	// http://www.applelogic.org/files/GSHARDWAREREF.pdf
+
+	size := image.Rect(0, 0, shrWidth, shrHeight)
+	img := image.NewRGBA(size)
+
+	// Load the palletes
+	palleteMem := a.mmu.physicalMainRAMAlt.subRange(shrColorPalettesAddress, shrColorPalettesAddressEnd)
+	colors := make([]color.Color, palettesCount)
+	iMem := 0
+	for i := 0; i < palettesCount; i++ {
+		b0 := palleteMem[iMem]
+		iMem++
+		b1 := palleteMem[iMem]
+		iMem++
+
+		red := (b0 & 0x0f) << 4
+		green := b1 & 0xf0
+		blue := (b1 & 0x0f) << 4
+
+		colors[i] = color.RGBA{red, green, blue, 255}
+	}
+
+	// See "Apple IIGS Hardware Reference", table 4-21
+	palettesSelectionTable := []uint8{0x4, 0x0, 0xc, 0x8}
+
+	// Build the lines
+	for y := 0; y < shrHeight; y++ {
+		controlByte := a.mmu.physicalMainRAMAlt.peek(shrScanLineControlAddress + uint16(y))
+		is640Wide := (controlByte & 0x80) != 0
+		isColorFill := (controlByte & 0x20) != 0
+		palleteIndex := (controlByte & 0x0f) << 4
+
+		lineAddress := shrPixelDataAddress + uint16(shrWidthBytes*y)
+		lineBytes := a.mmu.physicalMainRAMAlt.subRange(lineAddress, uint16(lineAddress+shrWidthBytes))
+
+		if is640Wide {
+			// Line is 640 pixels, two bits per pixel
+			x := 0
+			for i := 0; i < shrWidthBytes; i++ {
+				b := lineBytes[i]
+				for j := 3; j >= 0; j-- {
+					p := (b >> (uint(j) * 2)) & 0x03
+					offset := palettesSelectionTable[j]
+					color := colors[palleteIndex+offset+p]
+					img.Set(x, y, color)
+					x++
+				}
+			}
+		} else {
+			// Line is 320 pixels, two pixels per byte
+			x := 0
+			previousColor := uint8(0)
+			for i := 0; i < shrWidthBytes; i++ {
+				p0 := (lineBytes[i] & 0xf0) >> 4
+				if isColorFill && p0 == 0 {
+					p0 = previousColor
+				} else {
+					previousColor = p0
+				}
+				p1 := lineBytes[i] & 0x0f
+				if isColorFill && p1 == 0 {
+					p1 = previousColor
+				} else {
+					previousColor = p1
+				}
+				img.Set(x, y, colors[palleteIndex+p0])
+				img.Set(x+1, y, colors[palleteIndex+p0])
+				img.Set(x+2, y, colors[palleteIndex+p1])
+				img.Set(x+3, y, colors[palleteIndex+p1])
+				x += 4
+			}
+		}
+	}
+
+	return img
+}

softSwitches2.go

@@ -80,6 +80,12 @@ func notImplementedSoftSwitchR(*ioC0Page) uint8 {
 func notImplementedSoftSwitchW(*ioC0Page, uint8) {
 }
 
+func setStatusSoftSwitch(ioFlag uint8) softSwitchW {
+	return func(io *ioC0Page, value uint8) {
+		io.softSwitchesData[ioFlag] = value
+	}
+}
+
 func getStatusSoftSwitch(ioFlag uint8) softSwitchR {
 	return func(io *ioC0Page) uint8 {
 		return io.softSwitchesData[ioFlag]

softSwitches2e.go

@@ -8,7 +8,11 @@ package apple2
 const (
 	ioFlagAltChar uint8 = 0x1E
 	ioFlag80Col   uint8 = 0x1F
-	// ??? ioVertBlank uin8 = 0x19
+)
+
+const (
+	screenDrawCycles         = uint64(12480 + 4550)
+	screenVertBlankingCycles = uint64(4550)
 )
 
 func addApple2ESoftSwitches(io *ioC0Page) {
@@ -38,8 +42,19 @@ func addApple2ESoftSwitches(io *ioC0Page) {
 		return ssFromBool(mmu.lcActiveRead)
 	}, "BSRREADRAM")
 
-	// TOOD:
-	// VBL or VERTBLANK read on 0x19
+	io.addSoftSwitchR(0x19, func(_ *ioC0Page) uint8 {
+		// See "Inside Apple IIe", page 268
+		// See http://rich12345.tripod.com/aiivideo/vbl.html
+		// For each screen draw:
+		//      12480 cycles drawing lines, VERTBLANK = $00
+		//       4550 cycles doing the return to position (0,0), VERTBLANK = $80
+		// Vert blank takes 12480 cycles every page redraw
+		cycles := io.apple2.cpu.GetCycles() % screenDrawCycles
+		if cycles <= screenVertBlankingCycles {
+			return ssOn
+		}
+		return ssOff
+	}, "VERTBLANK")
 
 	//io.softSwitchesData[ioFlagAltChar] = ssOn // Not sure about this.