6 ex__gui__splitpane_8c
gullradriel edited this page 2026-10-09 00:55:18 +02:00

examples/ex_gui_splitpane.c

Functions

Name
int process_args(int argc, char ** argv)
void on_button_click(int widget_id, void * user_data)
void mouse_button(N_GUI_CTX * gui, int down, float x, float y)
int main(int argc, char ** argv)
void expect_true(const char * label, int cond)
void expect_close(const char * label, float got, float want, float tol)
void click_at(N_GUI_CTX * gui, float x, float y)

Attributes

Name
int log_level
int failures
int clicks

Defines

Name
ALLEGRO_UNSTABLE

Functions Documentation

function process_args

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

function on_button_click

static void on_button_click(
    int widget_id,
    void * user_data
)

function mouse_button

static void mouse_button(
    N_GUI_CTX * gui,
    int down,
    float x,
    float y
)

function main

int main(
    int argc,
    char ** argv
)

function expect_true

static void expect_true(
    const char * label,
    int cond
)

function expect_close

static void expect_close(
    const char * label,
    float got,
    float want,
    float tol
)

function click_at

static void click_at(
    N_GUI_CTX * gui,
    float x,
    float y
)

Attributes Documentation

variable log_level

static int log_level = 3;

variable failures

static int failures = 0;

variable clicks

static int clicks = 0;

Macros Documentation

define ALLEGRO_UNSTABLE

#define ALLEGRO_UNSTABLE 1

Source code

/*
 * Nilorea Library
 * Copyright (C) 2005-2026 Castagnier Mickael
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * SPDX-License-Identifier: Apache-2.0
 */


#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 int process_args(int argc, char** argv) {
    int opt;
    while ((opt = getopt(argc, argv, "V:")) != -1) {
        switch (opt) {
            case 'V':
                if (!strcmp("LOG_NULL", optarg))
                    log_level = LOG_NULL;
                else if (!strcmp("LOG_NOTICE", optarg))
                    log_level = LOG_NOTICE;
                else if (!strcmp("LOG_INFO", optarg))
                    log_level = LOG_INFO;
                else if (!strcmp("LOG_ERR", optarg))
                    log_level = LOG_ERR;
                else if (!strcmp("LOG_DEBUG", optarg))
                    log_level = LOG_DEBUG;
                else
                    return -1;
                break;
            default:
                return -1;
        }
    }
    return 0;
}

static void expect_close(const char* label, float got, float want, float tol) {
    float d = got - want;
    if (d < 0) d = -d;
    if (d > tol) {
        n_log(LOG_ERR, "%s: got %.3f, expected %.3f", label, got, want);
        failures++;
    }
}

static void expect_true(const char* label, int cond) {
    if (!cond) {
        n_log(LOG_ERR, "%s: condition false", label);
        failures++;
    }
}

static int clicks = 0;

static void on_button_click(int widget_id, void* user_data) {
    (void)widget_id;
    (void)user_data;
    clicks++;
}

/* Feed one synthetic mouse button event to the GUI. */
static void mouse_button(N_GUI_CTX* gui, int down, float x, float y) {
    ALLEGRO_EVENT ev;
    memset(&ev, 0, sizeof(ev));
    ev.type = down ? ALLEGRO_EVENT_MOUSE_BUTTON_DOWN : ALLEGRO_EVENT_MOUSE_BUTTON_UP;
    ev.mouse.button = 1;
    ev.mouse.x = (int)x;
    ev.mouse.y = (int)y;
    n_gui_process_event(gui, ev);
}

static void click_at(N_GUI_CTX* gui, float x, float y) {
    mouse_button(gui, 1, x, y);
    mouse_button(gui, 0, x, y);
}

int main(int argc, char** argv) {
    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) {
        n_log(LOG_ERR, "al_create_builtin_font failed");
        return 1;
    }
    N_GUI_CTX* gui = n_gui_new_ctx(font);
    if (!gui) {
        n_log(LOG_ERR, "n_gui_new_ctx failed");
        al_destroy_font(font);
        return 1;
    }
    n_gui_set_display_size(gui, 800.0f, 600.0f);

    int win = n_gui_add_window(gui, "Panel", 0.0f, 0.0f, 800.0f, 600.0f);
    expect_true("window created", win >= 0);

    int sp = n_gui_add_splitpane(gui, win, 0.0f, 0.0f, 800.0f, 600.0f, N_GUI_SPLIT_VERTICAL, 0.5f, NULL, NULL);
    expect_true("splitpane created", sp >= 0);
    expect_close("initial ratio", n_gui_splitpane_get_ratio(gui, sp), 0.5f, 0.001f);

    n_gui_splitpane_set_ratio(gui, sp, 0.8f);
    expect_close("set ratio 0.8", n_gui_splitpane_get_ratio(gui, sp), 0.8f, 0.001f);

    /* default clamp is [0.05, 0.95] */
    n_gui_splitpane_set_ratio(gui, sp, 2.0f);
    expect_close("clamp high to 0.95", n_gui_splitpane_get_ratio(gui, sp), 0.95f, 0.001f);
    n_gui_splitpane_set_ratio(gui, sp, -1.0f);
    expect_close("clamp low to 0.05", n_gui_splitpane_get_ratio(gui, sp), 0.05f, 0.001f);

    /* tighten the limits and confirm the stored ratio is pulled into range */
    n_gui_splitpane_set_limits(gui, sp, 0.2f, 0.7f);
    expect_close("ratio pulled to new min", n_gui_splitpane_get_ratio(gui, sp), 0.2f, 0.001f);
    n_gui_splitpane_set_ratio(gui, sp, 0.9f);
    expect_close("clamp to new max 0.7", n_gui_splitpane_get_ratio(gui, sp), 0.7f, 0.001f);

    /* Click routing. A split pane spans the whole region it splits, so a press
       that misses the divider band must fall through to whatever sits beneath
       it: two crossing panes stay independently draggable and the widgets in
       the panes keep receiving their clicks. */
    {
        int win2 = n_gui_add_window(gui, "Panes", 0.0f, 0.0f, 400.0f, 400.0f);
        int sp_v = -1, sp_h = -1, btn = -1;
        expect_true("second window created", win2 >= 0);
        n_gui_window_set_flags(gui, win2, N_GUI_WIN_FRAMELESS | N_GUI_WIN_FIXED_POSITION);

        sp_v = n_gui_add_splitpane(gui, win2, 0.0f, 0.0f, 400.0f, 400.0f, N_GUI_SPLIT_VERTICAL, 0.5f, NULL, NULL);
        sp_h = n_gui_add_splitpane(gui, win2, 0.0f, 0.0f, 400.0f, 400.0f, N_GUI_SPLIT_HORIZONTAL, 0.25f, NULL, NULL);
        btn = n_gui_add_button(gui, win2, "B", 300.0f, 300.0f, 60.0f, 24.0f,
                               N_GUI_SHAPE_RECT, on_button_click, NULL);
        expect_true("panes and button created", sp_v >= 0 && sp_h >= 0 && btn >= 0);

        /* vertical divider sits at x = 200, horizontal one at y = 100 */
        mouse_button(gui, 1, 200.0f, 300.0f);
        expect_true("press on vertical divider starts its drag",
                    gui->scrollbar_drag_widget_id == sp_v);
        mouse_button(gui, 0, 200.0f, 300.0f);

        /* the horizontal pane was added last (drawn on top), yet the vertical
           one is still reachable: neither swallows the other's band */
        mouse_button(gui, 1, 60.0f, 100.0f);
        expect_true("press on horizontal divider starts its drag",
                    gui->scrollbar_drag_widget_id == sp_h);
        mouse_button(gui, 0, 60.0f, 100.0f);

        /* a press over the panes but off both bands drags nothing */
        mouse_button(gui, 1, 60.0f, 250.0f);
        expect_true("press off both bands starts no drag",
                    gui->scrollbar_drag_widget_id == -1);
        mouse_button(gui, 0, 60.0f, 250.0f);

        /* and a widget under the panes still gets its click */
        clicks = 0;
        click_at(gui, 320.0f, 310.0f);
        expect_true("button beneath the panes still receives its click", clicks == 1);
    }

    n_gui_destroy_ctx(&gui);
    al_destroy_font(font);

    if (failures) {
        n_log(LOG_ERR, "ex_gui_splitpane: %d failure(s)", failures);
        return 1;
    }
    n_log(LOG_NOTICE, "ex_gui_splitpane: all checks passed");
    return 0;
}