Help info with F1

README.md

@@ -168,24 +168,6 @@ Line:
 
 ```
 
-### Keys
-
-- Ctrl-F1: Reset button
-- F5: Toggle speed between real and fastest
-- Ctrl-F5: Show current speed in Mhz
-- F6: Toggle between NTSC color TV and green phosphor monochrome monitor
-- F7: Show the video mode and a split screen with the views for NTSC color TV, page 1, page 2 and extra info.
-- F10: Cycle character generator code pages. Only if the character generator ROM has more than one 2Kb page.
-- Ctrl-F10: Show the charater map for the current character generator page.
-- Shift-F10: When showing the character map, use altText.
-- F11: Toggle on and off the trace to console of the CPU execution
-- F12: Save a screen snapshot to a file `snapshot.png`
-- Pause: Pause the emulation
-
-Drag and drop a diskette file on the left side of the window to change Drive 1; to the right side to change the disk on Drive 2.
-
-Only valid on SDL mode
-
 ### Command line options
 
 <!-- doc/usage.txt start -->

frontend/a2sdl/main.go

@@ -39,7 +39,9 @@ func sdlRun(a *izapple2.Apple2) {
 
 	defer window.Destroy()
 	defer renderer.Destroy()
-	window.SetTitle("iz-" + a.Name)
+
+	title := "iz-" + a.Name + " (F1 for help)"
+	window.SetTitle(title)
 
 	sdl.SetHint(sdl.HINT_RENDER_SCALE_QUALITY, "best")
 
@@ -96,16 +98,18 @@ func sdlRun(a *izapple2.Apple2) {
 
 		if paused != a.IsPaused() {
 			if a.IsPaused() {
-				window.SetTitle("iz-" + a.Name + " - PAUSED!")
+				window.SetTitle(title + " - PAUSED!")
 			} else {
-				window.SetTitle("iz-" + a.Name)
+				window.SetTitle(title)
 			}
 			paused = a.IsPaused()
 		}
 
 		if !a.IsPaused() {
 			var img *image.RGBA
-			if kp.showCharGen {
+			if kp.showHelp {
+				img = screen.SnapshotMessageGenerator(a, helpMessage)
+			} else if kp.showCharGen {
 				img = screen.SnapshotCharacterGenerator(a, kp.showAltText)
 				window.SetTitle(fmt.Sprintf("%v character map", a.Name))
 			} else if kp.showPages {
@@ -142,3 +146,29 @@ func sdlRun(a *izapple2.Apple2) {
 	}
 
 }
+
+var helpMessage = `
+
+        F1: Show/Hide help
+   Ctrl-F2: Reset
+        F5: Fast/Normal speed
+   Ctrl-F5: Show speed
+        F6: Next screen mode
+        F7: Show/Hide pages
+       F10: Next character set
+  Ctrl-F10: Show/Hide character set
+ Shift-F10: Show/Hide alternate text
+       F11: Show/Hide CPU trace
+       F12: Save screen snapshot
+	 Pause: Pause the emulation
+
+ Drop a file on the left or right
+ side of the window to load a disk
+
+ Run izapple2 -h for more options
+
+ More info at
+   https://github.com/ivanizag/izapple2
+`
+
+///////////////////////////////////////

frontend/a2sdl/sdlKeyboard.go

@@ -12,6 +12,7 @@ type sdlKeyboard struct {
 	a          *izapple2.Apple2
 	keyChannel *izapple2.KeyboardChannel
 
+	showHelp    bool
 	showPages   bool
 	showCharGen bool
 	showAltText bool
@@ -40,6 +41,7 @@ func (k *sdlKeyboard) putKey(keyEvent *sdl.KeyboardEvent) {
 		20 PRINT A, A - 128
 		30 GOTO 10
 	*/
+
 	if keyEvent.Type != sdl.KEYDOWN {
 		// Process only key pushes
 		return
@@ -87,11 +89,13 @@ func (k *sdlKeyboard) putKey(keyEvent *sdl.KeyboardEvent) {
 		result = 127 // 24 in the Base64A
 
 	// Base64A clone particularities
-	case sdl.K_F2:
+	case sdl.K_F3:
 		result = 127 // Base64A
 
 	// Control of the emulator
 	case sdl.K_F1:
+		k.showHelp = !k.showHelp
+	case sdl.K_F2:
 		if ctrl {
 			k.a.SendCommand(izapple2.CommandReset)
 		}

screen/snapshotsDebug.go

@@ -3,6 +3,7 @@ package screen
 import (
 	"image"
 	"image/color"
+	"strings"
 )
 
 // SnapshotParts the currently visible screen
@@ -154,5 +155,28 @@ func SnapshotCharacterGenerator(vs VideoSource, isAltText bool) *image.RGBA {
 		}
 	}
 
-	return renderText(vs, text, isAltText, nil, color.White)
+	snap := renderText(vs, text, isAltText, nil, color.White)
+	snap = linesSeparatedFilter(snap)
+	return snap
+}
+
+// SnapshotMessageGenerator shows a message on the screen
+func SnapshotMessageGenerator(vs VideoSource, message string) *image.RGBA {
+	lines := strings.Split(message, "\n")
+	text := make([]uint8, textLines*text40Columns)
+	for i := range text {
+		text[i] = 0x20 + 0x80 // Space
+	}
+
+	for l, line := range lines {
+		for c, char := range line {
+			if c < text40Columns && l < textLines {
+				text[text40Columns*l+c] = uint8(char) + 0x80
+			}
+		}
+	}
+
+	snap := renderText(vs, text, false, nil, color.White)
+	snap = linesSeparatedFilter(snap)
+	return snap
 }