// ef
//  introducing structures and functions for vectors and matrices
//
//  The origin of this screen is at the center.
//  This program demonstrates translation examples.
// T. Kosaka CS TNCT 1Aug2002

#include <stdio.h>
#include <math.h>
#include <GL/glut.h>
#include "drawtools2D.h"

void userdraw(void);

void display(void)
{
    glClear( GL_COLOR_BUFFER_BIT);
    userdraw();
    glutSwapBuffers();
}

//////////////////////////////////////////////////////////////////
void drawcharX(float x,float y) //文字 x の表示
{
    drawLine(x,y,x+10,y+12);drawLine(x,y+12,x+10,y);
}

void drawcharY(float x,float y) //文字 y の表示
{
    drawLine(x+5,y,x+5,y+7);drawLine(x,y+12,x+5,y+7);drawLine(x+10,y+12,x+5,y+7);
}

void drawAxes(void) // xy軸の表示
{
    drawLine(-310,0,310,0);drawLine(310,0,300,5);drawLine(310,0,300,-5);
    drawcharX(300,-20);
    drawLine(0,-230,0,230);drawLine(0,230,5,220);drawLine(0,230,-5,220);
    drawcharY(-20,220);
}
//////////////////////////////////////////////////////////////////
void userdraw(void)
{
    static int tick=0;
    int disp=(tick/100)%5;
    point2D_t ef[10]={
        {10,100},{10,10},{30,10},{30,40},{60,40},
        {60,60},{30,60},{30,80},{70,80},{70,100}
    };
    vector2D_t vec[10];
    matrix2D_t trans,rot,scale,refxaxis,refyaxis,reforg;
    color_t white={1.,1.,1.};
    color_t cyan={0.,1.,1.};
    int i,loop;
    setColor(white);
    drawAxes();
    setColor(cyan);
    drawPolygon(ef,10);
    switch(disp) {
    case 0:
        glutSetWindowTitle("matrixvector");
        break;
    case 1: //translation
        glutSetWindowTitle("matrixvector - translation");
        trans=translationMTX(62,22);
        for (i=0;i<10;i++) vec[i]=Point2Vector(ef[i]);
        for (loop=0;loop<4;loop++) {
            for (i=0;i<10;i++) vec[i]=multiply(trans,vec[i]);
            /* for (i=0;i<10;i++) vec[i]=trans*vec[i];  ....これでも同じ意味*/
            drawPolygon(vec,10);
        }
        break;
    case 2: //rotation
        glutSetWindowTitle("matrixvector - rotation");
        rot=rotationMTX(1.);
        for (i=0;i<10;i++) vec[i]=Point2Vector(ef[i]);
        for (loop=0;loop<4;loop++) {
            for (i=0;i<10;i++) vec[i]=multiply(rot,vec[i]);
            /* for (i=0;i<10;i++) vec[i]=rot*vec[i];  ....これでも同じ意味*/
            drawPolygon(vec,10);
        }
        break;
    case 3: //scaling
        glutSetWindowTitle("matrixvector - scaling");
        scale=scalingMTX(1.2,1.2);
        for (i=0;i<10;i++) vec[i]=Point2Vector(ef[i]);
        for (loop=0;loop<4;loop++) {
            for (i=0;i<10;i++) vec[i]=multiply(scale,vec[i]);
            /* for (i=0;i<10;i++) vec[i]=scale*vec[i];  ....これでも同じ意味*/
            drawPolygon(vec,10);
        }
        break;
    case 4:  //reflection a special case of scaling
        glutSetWindowTitle("matrixvector - reflection");
        refxaxis=scalingMTX(1.,-1.);
        refyaxis=scalingMTX(-1.,1.);
        reforg=scalingMTX(-1.,-1.);
        for (i=0;i<10;i++) {
            vec[i]=Point2Vector(ef[i]);
            vec[i]=multiply(refxaxis,vec[i]);
            /*  vec[i]=refxaxis*vec[i]　....これでも同じ意味*/
        }
        drawPolygon(vec,10);
        for (i=0;i<10;i++) {
            vec[i]=Point2Vector(ef[i]);
            vec[i]=multiply(refyaxis,vec[i]);
            /*  vec[i]=refyaxis*vec[i]　....これでも同じ意味*/
        }
        drawPolygon(vec,10);
        for (i=0;i<10;i++) {
            vec[i]=Point2Vector(ef[i]);
            vec[i]=multiply(reforg,vec[i]);
            /*  vec[i]=reforg*vec[i]　....これでも同じ意味*/
        }
        drawPolygon(vec,10);
        break;
    default:
        break;
    }
    tick++;
}

int main(int argc, char **argv)
{
    glutInit(&argc,argv);
    glutInitDisplayMode ( GLUT_DOUBLE | GLUT_RGB );
    glutInitWindowPosition(100,100);
    glutInitWindowSize(640,480);
    glutCreateWindow ("matrixvector");
    glClearColor(0.0, 0.0, 0.0, 0.0);
    gluOrtho2D(-320., 320., -240.0, 240.0);
      // Define the dimensions of the Orthographic Viewing Volume
    glutIdleFunc(display); // idle event call back
    glutDisplayFunc(display);
    glutMainLoop();
    return 0;
}