Кроссплатформенный GLUT: процедуры

#include <glut.cc>

SCREEN(13,0);

// Обработчик окна при вызове таймера
void display()  {

    for (int i = 0; i < 200; i++)
    for (int j = 0; j < 320; j++)
        pset(j, i, dac(i*j/200));

    update();
}

§ makefile

all:
	g++ main.cc -DLINUX_HOST -Ilib -O3 -lGL -lGLU -lglut -o main
	strip main
	./main

§ make.bat

@echo off

REM Only windows, only hardcore
REM g++ main.cc -Ilib -mwindows -O3 glut32.lib -lopengl32 -lglu32 -m32 -o main.exe

REM Console Edition Lite
g++ main.cc -Ilib -O3 lib/glut32.lib -lopengl32 -lglu32 -m32 -o main.exe

if %errorlevel% neq 0 goto :stop
strip main.exe
main.exe
goto :end
:stop
pause
:end

§ lib/glut.cc

#include "glut.h"

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

// Запустить экран
void screen(int mode) {

    int   argc = 0;
    char* argv[1];

    switch (mode) {

        case 12: app_width = 640; app_height = 480; app_factor = 1; break;
        case 13: app_width = 640; app_height = 400; app_factor = 2; break;
        default: exit(1);
    }

    // Инициализация переменных
    app_interval = 25;

    // Запустить окно
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA);
    glutInitWindowSize(app_width, app_height);
    glutInitWindowPosition(0, 0);
    glutCreateWindow("GLUT BASIC");
    glClearColor(0.0, 0.0, 0.0, 0.0);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluOrtho2D(-1.0, 1.0, -1.0, 1.0);

    // Выделить необходимую область памяти
    app_membuf = (unsigned char*) malloc(app_width * app_height * 4);
}

void start(int interval) {

    glutDisplayFunc(display);

    if (interval) {

        app_interval = interval;
        timer_function(0);
    }

    glutMainLoop();
}

// Обработчик таймера
void timer_function(int value) {

    glutPostRedisplay();
    glutTimerFunc(app_interval, timer_function, 0);
}

// Преобразовать цвет в DOS
int dac(int c) {
    return doscolortable[c & 255];
}

// Нарисовать точку
void pset(int x, int y, unsigned int cl) {

    x *= app_factor;
    y *= app_factor;

    if (x < 0 || y < 0 || x >= app_width || y >= app_height)
        return;

    for (int i = 0; i < app_factor; i++)
    for (int j = 0; j < app_factor; j++) {

        int cursor = 4*(j+x + (app_height-1-i-y)*app_width);
        app_membuf[cursor++] = cl>>16;
        app_membuf[cursor++] = cl>>8;
        app_membuf[cursor++] = cl;
        app_membuf[cursor++] = 255;
    }
}

// Получение точки с учетом factor
int point(int x, int y) {

    x *= app_factor;
    y *= app_factor;

    int cursor = 4*(x + (app_height-1-y)*app_width);

    unsigned char r = app_membuf[cursor  ];
    unsigned char g = app_membuf[cursor+1];
    unsigned char b = app_membuf[cursor+2];

    return (r*65536 + g*256 + b);
}

// Обновить экран
void update() {

    glRasterPos2i(-1, -1);
    glDrawPixels(app_width, app_height, GL_RGBA, GL_UNSIGNED_BYTE, app_membuf);
    glutSwapBuffers();
}

// Сохранение изображения в PPM
void saveppm(const char* filename) {

    char temp[256];

    int w = app_width  / app_factor;
    int h = app_height / app_factor;

    FILE* fp = fopen(filename, "wb");
    if (fp == NULL) exit(2);

    sprintf(temp, "P6\n%d %d\n255\n", w, h);
    fputs(temp, fp);

    for (int y = 0; y < h; y++)
    for (int x = 0; x < w; x++) {

        int p = point(x, y);

        temp[0] = p>>16;
        temp[1] = p>>8;
        temp[2] = p;

        fwrite(temp, 1, 3, fp);
    }

    fclose(fp);
}

§ lib/glut.h

#ifndef LINUX_HOST
#include <windows.h>
#endif
#include <GL/glut.h>

// Макросы
#define SCREEN(x,y) int main(int argc, char* argv[]) { screen(x); start(y); return 0; }

// Свойства
int app_width, app_height, app_factor;
int app_interval;

unsigned char* app_membuf;

// Процедуры
void    screen(int);        // Режим экрана
void    start(int);         // Запуск в работу
int     dac(int c);
void    pset(int, int, unsigned int cl);
void    update();

// Должны быть реализованы как часть движка
void    display();
void    timer_function(int);

// Таблица цветов DOS
static const int doscolortable[256] = {
    0x000000, 0x0000aa, 0x00aa00, 0x00aaaa, 0xaa0000, 0xaa00aa, 0xaa5500, 0xaaaaaa, // 0
    0x555555, 0x5555ff, 0x55ff55, 0x55ffff, 0xff5555, 0xff55ff, 0xffff55, 0xffffff, // 8
    0x000000, 0x141414, 0x202020, 0x2c2c2c, 0x383838, 0x454545, 0x515151, 0x616161, // 10
    0x717171, 0x828282, 0x929292, 0xa2a2a2, 0xb6b6b6, 0xcbcbcb, 0xe3e3e3, 0xffffff, // 18
    0x0000ff, 0x4100ff, 0x7d00ff, 0xbe00ff, 0xff00ff, 0xff00be, 0xff007d, 0xff0041, // 20
    0xff0000, 0xff4100, 0xff7d00, 0xffbe00, 0xffff00, 0xbeff00, 0x7dff00, 0x41ff00, // 28
    0x00ff00, 0x00ff41, 0x00ff7d, 0x00ffbe, 0x00ffff, 0x00beff, 0x007dff, 0x0041ff, // 30
    0x7d7dff, 0x9e7dff, 0xbe7dff, 0xdf7dff, 0xff7dff, 0xff7ddf, 0xff7dbe, 0xff7d9e, // 38
    0xff7d7d, 0xff9e7d, 0xffbe7d, 0xffdf7d, 0xffff7d, 0xdfff7d, 0xbeff7d, 0x9eff7d, // 40
    0x7dff7d, 0x7dff9e, 0x7dffbe, 0x7dffdf, 0x7dffff, 0x7ddfff, 0x7dbeff, 0x7d9eff, // 48
    0xb6b6ff, 0xc7b6ff, 0xdbb6ff, 0xebb6ff, 0xffb6ff, 0xffb6eb, 0xffb6db, 0xffb6c7, // 50
    0xffb6b6, 0xffc7b6, 0xffdbb6, 0xffebb6, 0xffffb6, 0xebffb6, 0xdbffb6, 0xc7ffb6, // 58
    0xb6ffb6, 0xb6ffc7, 0xb6ffdb, 0xb6ffeb, 0xb6ffff, 0xb6ebff, 0xb6dbff, 0xb6c7ff, // 60
    0x000071, 0x1c0071, 0x380071, 0x550071, 0x710071, 0x710055, 0x710038, 0x71001c, // 68
    0x710000, 0x711c00, 0x713800, 0x715500, 0x717100, 0x557100, 0x387100, 0x1c7100, // 70
    0x007100, 0x00711c, 0x007138, 0x007155, 0x007171, 0x005571, 0x003871, 0x001c71, // 78
    0x383871, 0x453871, 0x553871, 0x613871, 0x713871, 0x713861, 0x713855, 0x713845, // 80
    0x713838, 0x714538, 0x715538, 0x716138, 0x717138, 0x617138, 0x557138, 0x457138, // 88
    0x387138, 0x387145, 0x387155, 0x387161, 0x387171, 0x386171, 0x385571, 0x384571, // 90
    0x515171, 0x595171, 0x615171, 0x695171, 0x715171, 0x715169, 0x715161, 0x715159, // 98
    0x715151, 0x715951, 0x716151, 0x716951, 0x717151, 0x697151, 0x617151, 0x597151, // A0
    0x517151, 0x517159, 0x517161, 0x517169, 0x517171, 0x516971, 0x516171, 0x515971, // A8
    0x000041, 0x100041, 0x200041, 0x300041, 0x410041, 0x410030, 0x410020, 0x410010, // B0
    0x410000, 0x411000, 0x412000, 0x413000, 0x414100, 0x304100, 0x204100, 0x104100, // B8
    0x004100, 0x004110, 0x004120, 0x004130, 0x004141, 0x003041, 0x002041, 0x001041, // C0
    0x202041, 0x282041, 0x302041, 0x382041, 0x412041, 0x412038, 0x412030, 0x412028, // C8
    0x412020, 0x412820, 0x413020, 0x413820, 0x414120, 0x384120, 0x304120, 0x284120, // D0
    0x204120, 0x204128, 0x204130, 0x204138, 0x204141, 0x203841, 0x203041, 0x202841, // D8
    0x2c2c41, 0x302c41, 0x342c41, 0x3c2c41, 0x412c41, 0x412c3c, 0x412c34, 0x412c30, // E0
    0x412c2c, 0x41302c, 0x41342c, 0x413c2c, 0x41412c, 0x3c412c, 0x34412c, 0x30412c, // E8
    0x2c412c, 0x2c4130, 0x2c4134, 0x2c413c, 0x2c4141, 0x2c3c41, 0x2c3441, 0x2c3041, // F0
    0x000000, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000, 0x000000  // F8
};

22 сен, 2021