Graph (Kernel)ΒΆ

(Graph grGET_COLORS)
(Graph grDRAW_LINE y1 x1 y2 x2 [visualColor priColor ctlColor])
(Graph grSAVE_BOX y1 x1 y2 x2 [screen])
(Graph grRESTORE_BOX handle)
(Graph grFILL_BOX y1 x1 y2 x2 screens [visualColor priColor ctlColor])
(Graph grFILL_BOX_BACKGROUND y1 x1 y2 x2)
(Graph grFILL_BOX_FOREGROUND y1 x1 y2 x2)
(Graph grUPDATE_BOX screen)
(Graph grREDRAW_BOX y1 x1 y2 x2)
(Graph grADJUST_PRIORITY min max)

Graph is a kernel with many sub functions. It should be noted that the order of the coordinates (y, followed by x) is the opposite of most kernels.

Parameters:
  • y1 (number) – The top of the box.
  • x1 (number) – The left side of the box.
  • y2 (number) – The bottom of the box.
  • x2 (number) – The right side of the box.
  • screen (number) – A screen (VISUAL, PRIORITY or CONTROL).
  • screens (number) – A bitmask of VISUAL, PRIORITY or CONTROL.
  • handle (number) – A handle returned by grSAVE_BOX.
  • visualColor (number) – The color value for the visual screen.
  • priColor (number) – A priority value, or -1 to indicate none specified.
  • ctlColor (number) – A control color, or -1 to indicate none specified.
  • min (number) – The minimum priority band.
  • max (number) – The maximum priority band.
Returns:

Various values. See below.

The following functions are available:

grGET_COLORS
Obtains the color resolution which the interpreter is running in. Returns the number of colors.
grDRAW_LINE
Draws a line on the specified screen(s) with the specified color.
grSAVE_BOX
Saves the screen pixels in the specified area and returns a handle to them. If screen is specified, it saves the pixels of that screen (VISUAL,PRIORITY,CONTROL). Otherwise, it uses the VISUAL screen.
grRESTORE_BOX
Restores the pixels saved with grSAVE_BOX.
grFILL_BOX
Fills the specified rectangular region with the specified color(s). The screens parameter specifies which screens to drawn to.
grFILL_BOX_BACKGROUND
Operates just like grFILL_BOX, but draws a box on the visual screen with the current port’s background color.
grFILL_BOX_FOREGROUND
Operates just like grFILL_BOX, but draws a box on the visual screen with the current port’s foreground color.
grUPDATE_BOX
Draws the specified area of the specified screen to the screen. You can use this to redraw the background picture, and also to view the priority/control screens.
grREDRAW_BOX
Redraws the specified area of visual screen to the screen.
grADJUST_PRIORITY
Sets the minimum and maximum bounds for the priority. By default, these values are 42 and 190 in SCI0.

Example for grGET_COLORS:

(= colors (Graph grGET_COLORS))
(if (== colors 16)
        (Print "You are running in EGA mode")
else
        (if (== colors -1)
                (Print "You are running in CGA mode")
        else
                ; VGA returns 25 in the original interpreter, but 256 in ScummVM.
                (Print "You are probably in VGA mode")
        )
)

Example for grUPDATE_BOX:

; Shows the priority screen for two seconds
(Graph grUPDATE_BOX 0 0 199 319 PRIORITY)
(Wait 120)

; Shows the control screen for two seconds
(Graph grUPDATE_BOX 0 0 199 319 CONTROL)
(Wait 120)

; Shows the visual screen
(Graph grUPDATE_BOX 0 0 199 319 VISUAL)

Example for grFILL_BOX:

; Draws a box with the bounds of (30,20) and (200,100) on the visual screen in yellow, the priority screen in red, and the control screen in blue.
(Graph grDRAW_BOX 20 30 100 200 ALL_SCREENS clYELLOW clRED clBLUE)

; Doesn't draw anything though the colors are specified, no screens are
(Graph grDRAW_BOX 20 30 100 200 0 clYELLOW clRED clBLUE)

; Draws a box with the bounds of (60,40) and (160,130) on the visual screen in white, and the control screen in brown.
(Graph grDRAW_BOX 40 60 130 160 VISUAL_CONTROL clWHITE -1 clBROWN)

Example for grRESTORE_BOX and grSAVE_BOX:

; this saves the center of the screen, draws a line, then restores the area leaving only the line's edges
(= handle (Graph grSAVE_BOX 50 80 150 240))
(Graph grDRAW_LINE 10 10 180 310 clYELLOW)
(Graph grRESTORE_BOX handle)

Example for grDRAW_LINE:

; Draw a line from (30,20) to (200,100) on the visual screen in yellow, the priority screen in red, and the control screen in blue.
(Graph grDRAW_LINE 20 30 100 200 clYELLOW clRED clBLUE)

; Draw a line from (60,40) to (160,130) on the visual screen in white, and the control screen in brown.
(Graph grDRAW_LINE 40 60 130 160 clWHITE -1 clBROWN)

; Draw a line from (10,20) to (40,50) on the visual screen in red.
(Graph grDRAW_LINE 20 10 50 40 clRED)