Scriptel ScripTouch ProScript C Library This documentation contains information about the ScripTouch ProScript C Library.

example-image-cairo.c

This is a simple example of how to connect to a ScripTouch device and output a PNG image using the Cairo drawing library.

#include <stdio.h>
#include "scriptel-proscript.h"
#include "cairo.h"
scriptel_hid_feature_coordinate_range range;
cairo_surface_t* surface;
cairo_t* cr;
unsigned char penDown = 0;
void input_callback(scriptel_device* device, scriptel_input_report* report, unsigned char report_id) {
if(report_id == SCRIPTEL_INPUT_EXTENDEDCOORDINATE) {
//We got pen input, lets adjust the coordinates into screen aspect.
double x = device->display_info.width * ((report->extended_coordinate.x - range.x_min) / (double)(range.x_max - range.x_min));
double y = device->display_info.height * ((report->extended_coordinate.y - range.y_min) / (double)(range.y_max - range.y_min));
printf("Got a coordinate from the device: %4.2f, %4.2f\n", x, y);
if(report->extended_coordinate.sample_info.pen.tip_switch && !penDown) {
//Pen Down
cairo_move_to(cr, x, y);
penDown = 1;
} else {
//Pen Move / Pen Up
cairo_line_to(cr, x, y);
penDown = report->extended_coordinate.sample_info.pen.tip_switch;
if(!penDown) {
cairo_stroke(cr);
}
}
} else if(report_id == SCRIPTEL_INPUT_BUTTONPRESS) {
//A button was pressed, if it's the OK button we'll close the device.
char* caption = report->button_press.region->button.caption;
printf("Button pressed: %s\n", caption);
if(strcmp(caption, "OK") == 0) {
cairo_surface_write_to_png(surface, "signature_cairo.png");
//The OK button was hit, close the device.
scriptel_close_device(device);
} else {
//The cancel button was hit, clear the image.
cairo_set_source_rgba (cr, 0xFF, 0xFF, 0xFF, 0);
cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
cairo_paint (cr);
cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
cairo_set_source_rgba (cr, 0, 0, 0, 0xFF);
}
}
}
int main() {
scriptel_device* device;
//Initialize the library.
scriptel_init();
//List the devices.
if(scriptel_list_devices(&device) == SCRIPTEL_CODE_SUCCESS) {
//Test to see if we have more than zero devices.
if(device != NULL) {
printf("Found %i devices.\n", scriptel_count_device_list(device));
//Lets open the first device and get some information from it.
if(scriptel_open_device(device) == SCRIPTEL_CODE_SUCCESS) {
printf("Successfully connected to %s - %s at: %s\n", device->manufacturer, device->model, device->path);
//Register an input callback, this will be called when we get input from the pad.
scriptel_register_input_callback(device, input_callback);
//Get the coordinate scaling information we'll need later.
range = scriptel_get_coordinate_range(device);
//Start up Cairo
surface = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, device->display_info.width, device->display_info.height);
cr = cairo_create(surface);
cairo_set_line_width(cr, 1);
//Clear Image with Transparent
cairo_set_source_rgba (cr, 0xFF, 0xFF, 0xFF, 0);
cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
cairo_paint (cr);
cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
cairo_set_source_rgba (cr, 0, 0, 0, 0xFF);
//Wait for input from the pad.
while(device->open) {
scriptel_device_read(device);
}
cairo_surface_destroy(surface);
scriptel_free_device_list(device);
} else {
printf("Problem opening device: %s\n", scriptel_get_last_error());
return 1;
}
} else {
printf("No devices found!\n");
return 2;
}
} else {
printf("Problem enumerating devices: %s\n", scriptel_get_last_error());
return 3;
}
}
SCRIPTEL_INPUT_BUTTONPRESS
@ SCRIPTEL_INPUT_BUTTONPRESS
The report identifier of the button press input report.
Definition: scriptel-hid-reports.h:297
SCRIPTEL_INPUT_EXTENDEDCOORDINATE
@ SCRIPTEL_INPUT_EXTENDEDCOORDINATE
The report identifier of the extended coordinate input report.
Definition: scriptel-hid-reports.h:234
scriptel-proscript.h
This file contains the headers for the core of the Scriptel ScripTouch ProScript library.
scriptel_init
void scriptel_init(void)
This function should be called prior to using any other library functions.
scriptel_count_device_list
unsigned int scriptel_count_device_list(scriptel_device *list)
This function counts the number of devices in a given device list.
scriptel_get_coordinate_range
scriptel_hid_feature_coordinate_range scriptel_get_coordinate_range(scriptel_device *device)
This function gets the logical coordinate range that will be returned from the device when points are...
scriptel_list_devices
scriptel_error_code scriptel_list_devices(scriptel_device **start)
This function takes a pointer and will attempt to enumerate any attached ScripTouch devices.
scriptel_close_device
scriptel_error_code scriptel_close_device(scriptel_device *device)
This function attempts to close a local device that was previously opened.
scriptel_open_device
scriptel_error_code scriptel_open_device(scriptel_device *device)
This function attempts to open a local device returned by scriptel_list_devices().
scriptel_get_last_error
char * scriptel_get_last_error(void)
This function gets the last error message generated by the library.
scriptel_free_device_list
void scriptel_free_device_list(scriptel_device *device_list)
This function crawls a scriptel_device list and attempts to free any library managed memory associate...
SCRIPTEL_CODE_SUCCESS
@ SCRIPTEL_CODE_SUCCESS
This code indicates that the function did succeed.
Definition: scriptel-proscript.h:96
scriptel_device_read
scriptel_error_code scriptel_device_read(scriptel_device *device)
This function attempts to read from the passed in device.
scriptel_register_input_callback
void scriptel_register_input_callback(scriptel_device *device, scriptel_input_callback callback)
This function registers an input callback for a device.
scriptel_device_region_button::caption
char caption[100]
Caption of the button.
Definition: scriptel-hid-reports.h:2585
scriptel_device
This structure represents a physically attached Scriptel ScripTouch device.
Definition: scriptel-proscript.h:284
scriptel_device::path
char * path
The path to the device.
Definition: scriptel-proscript.h:290
scriptel_device::open
unsigned char open
Indicates whether or not the device is in the open state.
Definition: scriptel-proscript.h:319
scriptel_device::display_info
scriptel_hid_feature_display_info display_info
Cached display information from the device at open time.
Definition: scriptel-proscript.h:333
scriptel_device::model
char * model
The textual name of the device as returned by the operating system's HID driver.
Definition: scriptel-proscript.h:305
scriptel_device::manufacturer
char * manufacturer
The textual name of the manufacturer as returned by the operating system's HID driver.
Definition: scriptel-proscript.h:310
scriptel_hid_feature_coordinate_range
This report is capable of getting the coordinate range from the device.
Definition: scriptel-hid-reports.h:1582
scriptel_hid_feature_coordinate_range::x_max
unsigned short x_max
Maximum logical value in the horizontal direction to be returned by the device.
Definition: scriptel-hid-reports.h:1594
scriptel_hid_feature_coordinate_range::y_max
unsigned short y_max
Maximum logical value in the vertical direction to be returned by the device.
Definition: scriptel-hid-reports.h:1602
scriptel_hid_feature_coordinate_range::y_min
unsigned short y_min
Minimum logical value in the vertical direction to be returned by the device.
Definition: scriptel-hid-reports.h:1598
scriptel_hid_feature_coordinate_range::x_min
unsigned short x_min
Minimum logical value in the horizontal direction to be returned by the device.
Definition: scriptel-hid-reports.h:1590
scriptel_hid_feature_display_info::width
unsigned short width
Width of the on board display in pixels.
Definition: scriptel-hid-reports.h:2341
scriptel_hid_feature_display_info::height
unsigned short height
Height of the on board display in pixels.
Definition: scriptel-hid-reports.h:2347
scriptel_hid_input_button_press::region
scriptel_device_region_info * region
Button that was pressed.
Definition: scriptel-hid-reports.h:3712
scriptel_hid_input_extended_coordinate::x
unsigned short x
Horizontal component of the sample.
Definition: scriptel-hid-reports.h:897
scriptel_hid_input_extended_coordinate::y
unsigned short y
Vertical component of the sample.
Definition: scriptel-hid-reports.h:901
scriptel_hid_input_extended_coordinate::sample_info
scriptel_sample_info sample_info
Information about the sample that produced this coordinate.
Definition: scriptel-hid-reports.h:893
scriptel_sample_info_pen::tip_switch
unsigned char tip_switch
This will be true if the pen is currently against the screen.
Definition: scriptel-hid-reports.h:799
scriptel_device_region_info::button
scriptel_device_region_button button
Button region information.
Definition: scriptel-hid-reports.h:2625
scriptel_input_report
This union contains all valid input report types.
Definition: scriptel-hid-reports.h:3728
scriptel_input_report::extended_coordinate
scriptel_hid_input_extended_coordinate extended_coordinate
Extended coordinate report.
Definition: scriptel-hid-reports.h:3740
scriptel_input_report::button_press
scriptel_hid_input_button_press button_press
Button press report.
Definition: scriptel-hid-reports.h:3768
scriptel_sample_info::pen
scriptel_sample_info_pen pen
Sample information relevant to only pen input.
Definition: scriptel-hid-reports.h:853