HP Prime Graphing Calculator - Manual (Page 543)

Programming in HP PPL 537
coordinates using the Cartesian plane defined in the
current app by the variables Xmin, Xmax, Ymin, and
Ymax.
The remaining thirteen work with pixel coordinates where
the pixel 0,0 is the top left pixel of the GROB, and 320,
240 is the bottom right. Functions in this second set have
a _P suffix to the function name.
C→PX Converts from Cartesian coordinates to screen coordinates.
Syntax: C→PX(x,y) or C→PX({x,y})
DRAWMENU Syntax: DRAWMENU({string1, string2, …,
string6})
Draws string1 through string (for n≤6) on the menu
buttons.
FREEZE Syntax: FREEZE
Pauses program execution until a key is pressed. This
prevents the screen from being redrawn after the end of
the program execution, leaving the modified display on
the screen for the user to see.
PX→C Converts from screen coordinates to Cartesian
coordinates.
RGB Syntax: RGB(R, G, B, [A])
Returns an integer number that can be used as the color
parameter for a drawing function, based on Red-, Green-
and Blue-component values (each 0 to 255).
If Alpha is greater than 128, returns the color flagged as
transparent. There is no alpha channel blending on Prime.
Examples:
RGB(255,0,128) returns 16711808
RECT(RGB(0,0,255)) makes a blue screen
LINE(0,0,8,8,RGB(0,255,0)) draws a green line