6 ex__gui__custom__mouse_8c
gullradriel edited this page 2026-10-09 00:55:18 +02:00

examples/ex_gui_custom_mouse.c

Functions

Name
int was(int type, int button, float x, float y)
was the last thing told this
int process_args(int argc, char ** argv)
read -V LOGLEVEL
int on_mouse(int widget_id, const N_GUI_MOUSE_EVENT * ev, void * user_data)
the widget's mouse callback
int main(int argc, char ** argv)
int feed(N_GUI_CTX * gui, int type, int x, int y, int button, int dz)
feed one mouse event
void expect_true(const char * what, int ok)
record one check
void destroy_state(void * state)
the owned state's destructor

Attributes

Name
int wheel_answer
what the widget answers to a wheel
int told
int log_level
N_GUI_MOUSE_EVENT last
the last event the widget was told of, and how many
int failures
int destroyed
how many times the owned state was destroyed

Defines

Name
ALLEGRO_UNSTABLE

Functions Documentation

function was

static int was(
    int type,
    int button,
    float x,
    float y
)

was the last thing told this

function process_args

static int process_args(
    int argc,
    char ** argv
)

read -V LOGLEVEL

function on_mouse

static int on_mouse(
    int widget_id,
    const N_GUI_MOUSE_EVENT * ev,
    void * user_data
)

the widget's mouse callback

function main

int main(
    int argc,
    char ** argv
)

function feed

static int feed(
    N_GUI_CTX * gui,
    int type,
    int x,
    int y,
    int button,
    int dz
)

feed one mouse event

function expect_true

static void expect_true(
    const char * what,
    int ok
)

record one check

function destroy_state

static void destroy_state(
    void * state
)

the owned state's destructor

Attributes Documentation

variable wheel_answer

static int wheel_answer = 1;

what the widget answers to a wheel

variable told

static int told = 0;

variable log_level

static int log_level = 3;

variable last

static N_GUI_MOUSE_EVENT last;

the last event the widget was told of, and how many

variable failures

static int failures = 0;

variable destroyed

static int destroyed = 0;

how many times the owned state was destroyed

Macros Documentation

define ALLEGRO_UNSTABLE

#define ALLEGRO_UNSTABLE 1

Source code



#define ALLEGRO_UNSTABLE 1

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "nilorea/n_common.h"
#include "nilorea/n_log.h"
#include "nilorea/n_gui.h"

static int log_level = LOG_ERR;
static int failures = 0;

static N_GUI_MOUSE_EVENT last;
static int told = 0;
static int wheel_answer = 1;
static int destroyed = 0;

static void expect_true(const char* what, int ok) {
    if (!ok) {
        n_log(LOG_ERR, "FAIL: %s", what);
        failures++;
    } else {
        n_log(LOG_INFO, "ok: %s", what);
    }
}

static int process_args(int argc, char** argv) {
    int opt = 0;

    while ((opt = getopt(argc, argv, "V:")) != -1) {
        if (opt == 'V') {
            log_level = atoi(optarg);
        } else {
            return -1;
        }
    }
    return 0;
}

static int on_mouse(int widget_id, const N_GUI_MOUSE_EVENT* ev, void* user_data) {
    (void)widget_id;
    (void)user_data;
    last = *ev;
    told++;
    return ev->type == N_GUI_MOUSE_WHEEL ? wheel_answer : 1;
}

static void destroy_state(void* state) {
    destroyed++;
    free(state);
}

static int feed(N_GUI_CTX* gui, int type, int x, int y, int button, int dz) {
    ALLEGRO_EVENT ev;

    memset(&ev, 0, sizeof(ev));
    ev.type = (ALLEGRO_EVENT_TYPE)type;
    ev.mouse.x = x;
    ev.mouse.y = y;
    ev.mouse.dx = (type == ALLEGRO_EVENT_MOUSE_AXES && dz == 0) ? 1 : 0;
    ev.mouse.dz = dz;
    ev.mouse.button = (unsigned int)button;
    return n_gui_process_event(gui, ev);
}

static int was(int type, int button, float x, float y) {
    return last.type == type && last.button == button && last.x == x && last.y == y;
}

int main(int argc, char** argv) {
    int before = 0;

    set_log_level(LOG_ERR);
    if (process_args(argc, argv) != 0) {
        fprintf(stderr, "Usage: %s [-V LOG_LEVEL]\n", argv[0]);
        return 2;
    }
    set_log_level(log_level);
    if (!al_init() || !al_init_font_addon()) {
        n_log(LOG_ERR, "allegro init failed");
        return 1;
    }
    ALLEGRO_FONT* font = al_create_builtin_font();
    if (!font) return 1;
    N_GUI_CTX* gui = n_gui_new_ctx(font);
    if (!gui) {
        al_destroy_font(font);
        return 1;
    }
    n_gui_set_display_size(gui, 400.0f, 300.0f);
    int win = n_gui_add_window(gui, "W", 0.0f, 0.0f, 400.0f, 300.0f);
    n_gui_window_set_flags(gui, win, N_GUI_WIN_FRAMELESS);
    n_gui_open_window(gui, win);

    int area = n_gui_add_custom(gui, win, 50.0f, 50.0f, 100.0f, 80.0f, NULL, NULL);
    n_gui_custom_set_mouse(gui, area, on_mouse, NULL);

    feed(gui, ALLEGRO_EVENT_MOUSE_AXES, 60, 70, 0, 0);
    expect_true("a move over it is a MOVE, in its coordinates", told == 1 && was(N_GUI_MOUSE_MOVE, 0, 10.0f, 20.0f));
    feed(gui, ALLEGRO_EVENT_MOUSE_BUTTON_DOWN, 60, 70, 1, 0);
    expect_true("a left press is a DOWN with button 1", was(N_GUI_MOUSE_DOWN, 1, 10.0f, 20.0f));
    feed(gui, ALLEGRO_EVENT_MOUSE_AXES, 200, 200, 0, 0);
    expect_true("a drag out of it is still reported, as a DRAG", was(N_GUI_MOUSE_DRAG, 1, 150.0f, 150.0f));
    /* Allegro reports a move before a release somewhere new, so the pointer
       is where the last move left it */
    feed(gui, ALLEGRO_EVENT_MOUSE_AXES, 210, 190, 0, 0);
    expect_true("so is the next move of the drag", was(N_GUI_MOUSE_DRAG, 1, 160.0f, 140.0f));
    feed(gui, ALLEGRO_EVENT_MOUSE_BUTTON_UP, 210, 190, 1, 0);
    expect_true("the release is an UP where the pointer is", was(N_GUI_MOUSE_UP, 1, 160.0f, 140.0f));
    before = told;
    feed(gui, ALLEGRO_EVENT_MOUSE_AXES, 220, 220, 0, 0);
    expect_true("a move elsewhere after it is not reported", told == before);

    feed(gui, ALLEGRO_EVENT_MOUSE_BUTTON_DOWN, 70, 60, 2, 0);
    expect_true("a right press is a DOWN with button 2", was(N_GUI_MOUSE_DOWN, 2, 20.0f, 10.0f));
    feed(gui, ALLEGRO_EVENT_MOUSE_BUTTON_UP, 70, 60, 2, 0);

    before = told;
    expect_true("a wheel it takes is consumed", feed(gui, ALLEGRO_EVENT_MOUSE_AXES, 60, 70, 0, 1) == 1);
    expect_true("and reported with its steps", told == before + 1 && last.type == N_GUI_MOUSE_WHEEL && last.dz == 1);
    wheel_answer = 0;
    before = told;
    feed(gui, ALLEGRO_EVENT_MOUSE_AXES, 60, 70, 0, -1);
    expect_true("a wheel it declines is still reported", told == before + 1 && last.dz == -1);

    before = told;
    feed(gui, ALLEGRO_EVENT_MOUSE_BUTTON_DOWN, 300, 250, 1, 0);
    feed(gui, ALLEGRO_EVENT_MOUSE_BUTTON_UP, 300, 250, 1, 0);
    expect_true("a press elsewhere tells it nothing", told == before);

    /* a widget drawn over part of it takes the press there */
    n_gui_add_button(gui, win, "over", 50.0f, 50.0f, 30.0f, 20.0f, N_GUI_SHAPE_RECT, NULL, NULL);
    before = told;
    feed(gui, ALLEGRO_EVENT_MOUSE_BUTTON_DOWN, 55, 55, 1, 0);
    feed(gui, ALLEGRO_EVENT_MOUSE_BUTTON_UP, 55, 55, 1, 0);
    expect_true("a press on a widget over it does not reach it", told == before);

    n_gui_custom_set_mouse(gui, area, NULL, NULL);
    before = told;
    feed(gui, ALLEGRO_EVENT_MOUSE_BUTTON_DOWN, 100, 100, 1, 0);
    feed(gui, ALLEGRO_EVENT_MOUSE_BUTTON_UP, 100, 100, 1, 0);
    expect_true("with the callback taken away it is told nothing", told == before);

    /* ownership */
    int* state = malloc(sizeof(int));
    int owner = n_gui_add_custom(gui, win, 200.0f, 10.0f, 20.0f, 20.0f, NULL, state);
    n_gui_custom_set_destroy(gui, owner, destroy_state);
    n_gui_custom_set_destroy(gui, area, NULL);
    n_gui_destroy_ctx(&gui);
    expect_true("owned state is destroyed with the widget, once", destroyed == 1);

    al_destroy_font(font);
    if (failures) {
        fprintf(stderr, "ex_gui_custom_mouse: %d failure(s)\n", failures);
        return 1;
    }
    printf("ex_gui_custom_mouse: ok\n");
    return 0;
}