Add support to partial rendering of text

micropython/examples/galactic_unicorn/scrolling_text.py

@@ -1,6 +1,7 @@
 import time
 from galactic import GalacticUnicorn
 from picographics import PicoGraphics, DISPLAY_GALACTIC_UNICORN as DISPLAY
+# import random
 
 '''
 Display scrolling wisdom, quotes or greetz.
@@ -27,15 +28,16 @@
 
 # function for drawing outlined text
 def outline_text(text, x, y):
-    graphics.set_pen(graphics.create_pen(int(OUTLINE_COLOUR[0]), int(OUTLINE_COLOUR[1]), int(OUTLINE_COLOUR[2])))
-    graphics.text(text, x - 1, y - 1, -1, 1)
-    graphics.text(text, x, y - 1, -1, 1)
-    graphics.text(text, x + 1, y - 1, -1, 1)
-    graphics.text(text, x - 1, y, -1, 1)
-    graphics.text(text, x + 1, y, -1, 1)
-    graphics.text(text, x - 1, y + 1, -1, 1)
-    graphics.text(text, x, y + 1, -1, 1)
-    graphics.text(text, x + 1, y + 1, -1, 1)
+    if (OUTLINE_COLOUR != BACKGROUND_COLOUR):
+        graphics.set_pen(graphics.create_pen(int(OUTLINE_COLOUR[0]), int(OUTLINE_COLOUR[1]), int(OUTLINE_COLOUR[2])))
+        graphics.text(text, x - 1, y - 1, -1, 1)
+        graphics.text(text, x, y - 1, -1, 1)
+        graphics.text(text, x + 1, y - 1, -1, 1)
+        graphics.text(text, x - 1, y, -1, 1)
+        graphics.text(text, x + 1, y, -1, 1)
+        graphics.text(text, x - 1, y + 1, -1, 1)
+        graphics.text(text, x, y + 1, -1, 1)
+        graphics.text(text, x + 1, y + 1, -1, 1)
 
     graphics.set_pen(graphics.create_pen(int(MESSAGE_COLOUR[0]), int(MESSAGE_COLOUR[1]), int(MESSAGE_COLOUR[2])))
     graphics.text(text, x, y, -1, 1)
@@ -47,6 +49,9 @@ def outline_text(text, x, y):
 STATE_PRE_SCROLL = 0
 STATE_SCROLLING = 1
 STATE_POST_SCROLL = 2
+LENGTH_TO_TRIGGER_PARTIAL_RENDER = 50
+CHARS_TO_RENDER = 30
+CHARS_LEFT_RESET = 5
 
 shift = 0
 state = STATE_PRE_SCROLL
@@ -59,6 +64,14 @@ def outline_text(text, x, y):
 
 last_time = time.ticks_ms()
 
+message_display = MESSAGE
+partial_text = 0
+if (len(message_display) > LENGTH_TO_TRIGGER_PARTIAL_RENDER):
+    partial_text = 1
+    message_display = MESSAGE[0:CHARS_TO_RENDER]
+    current_char = 0
+msg_width = graphics.measure_text(message_display, 1)
+
 while True:
     time_ms = time.ticks_ms()
 
@@ -77,17 +90,32 @@ def outline_text(text, x, y):
         shift += 1
         if shift >= (msg_width + PADDING * 2) - width - 1:
             state = STATE_POST_SCROLL
+        current_char = 0
+        message_display = MESSAGE[0:CHARS_TO_RENDER]
         last_time = time_ms
 
     if state == STATE_POST_SCROLL and time_ms - last_time > HOLD_TIME * 1000:
         state = STATE_PRE_SCROLL
+        # MESSAGE_COLOUR = (random.randint(0,255), random.randint(0,255), random.randint(0,255)) # Uncomment this and the random import to make the display a new colour each rotation
         shift = 0
         last_time = time_ms
+
+    if (partial_text == 1 and PADDING - shift < -10):
+        char_size = graphics.measure_text(message_display[0:1], 1)
+        if (message_display[0:1] == ' '):
+            char_size -= 1
+        shift -= char_size
+        current_char += 1
+
+        message_display = MESSAGE[current_char:current_char+CHARS_TO_RENDER]
+        if (len(message_display) < CHARS_LEFT_RESET):
+            state = STATE_POST_SCROLL
+        last_time = time_ms
 
     graphics.set_pen(graphics.create_pen(int(BACKGROUND_COLOUR[0]), int(BACKGROUND_COLOUR[1]), int(BACKGROUND_COLOUR[2])))
     graphics.clear()
 
-    outline_text(MESSAGE, x=PADDING - shift, y=2)
+    outline_text(message_display, x=PADDING - shift, y=2)
 
     # update the display
     gu.update(graphics)