Make scroll work

libs/core/screen.cpp

@@ -23,6 +23,18 @@ enum class ScreenFont {
 
 // We only support up to 4 arguments for C++ functions - need to pack them on the TS side
 namespace screen {
+
+extern "C" {
+void DisplaySetPixel(byte X, byte Y);
+void DisplayClrPixel(byte X, byte Y);
+void DisplayXorPixel(byte X, byte Y);
+}
+
+void pokeScreen() {
+    DisplayXorPixel(0, 0);
+    DisplayXorPixel(0, 0);
+}
+
 //%
 void _drawLine(uint32_t p0, uint32_t p1, Draw mode) {
     DMESG("line %x %x %x", p0, p1, mode);
@@ -57,6 +69,8 @@ void clear() {
 //%
 void scroll(int v) {
     LcdScroll(v);
+    pokeScreen(); // missing in ev3-api
+    //LcdUpdate();
 }
 
 /** Set font for drawText() */
@@ -64,5 +78,4 @@ void scroll(int v) {
 void setFont(ScreenFont font) {
     LcdSelectFont((uint8_t)font);
 }
-
 }

libs/core/test.ts

@@ -1,23 +1,36 @@
 screen.clear()
 screen.setFont(ScreenFont.Large)
 screen.drawText(10, 30, "Hello PXT!")
-screen.drawRect(10, 70, 20, 10, Draw.Fill)
-screen.drawEllipse(40, 40, 20, 10)
 
-output.setLights(LightsPattern.GreenPulse)
+screen.drawEllipse(40, 40, 20, 10, Draw.Fill)
+output.setLights(LightsPattern.Orange)
+
+input.buttonEnter.onEvent(ButtonEvent.Click, () => {
+    screen.clear()
+})
+
+input.buttonLeft.onEvent(ButtonEvent.Click, () => {
+    screen.drawRect(10, 70, 20, 10, Draw.Fill)
+})
+
+input.buttonRight.onEvent(ButtonEvent.Click, () => {
+    screen.setFont(ScreenFont.Normal)
+    screen.drawText(10, 60, "Bang!")
+})
 
 input.buttonDown.onEvent(ButtonEvent.Click, () => {
-    screen.scroll(10)
+    screen.scroll(-10)
 })
 
 input.buttonUp.onEvent(ButtonEvent.Click, () => {
-    screen.scroll(-10)
+    screen.scroll(10)
 })
 
 for (let i = 0; i < 3; ++i) {
     loops.forever(() => {
         let r = Math.randomRange(0, 100)
         serial.writeValue("R", r)
+        //screen.drawText(10, 10, `R=${r}`)
         loops.pause(1000)
     })
     loops.pause(300)