쭉 긁으면 되는 소스 (3)

곡선 & 곡면

#pragma warning(disable:4996)
#include <iostream>
#include <vector>
#include <conio.h>
#include <gl/glut.h>
#include <gl/gl.h>
#include <gl/glu.h>
using namespace std;
 
//#define _1D 1
 
#ifdef _1D 
// The number of control points for this curve
GLint nNumPoints = 6;
 
GLfloat ctrlPoints[6][3] = {
    { -4.0f, 0.0f, 0.0f },    // End Point
    { -6.0f, 4.0f, 0.0f },    // Control Point
    { 0.0f, 4.0f, 0.0f },    // Control Point
    { 0.0f, -4.0f, 0.0f },    // Control Point
    { 6.0f, -4.0f, 0.0f },    // Control Point
    { 4.0f, 0.0f, 0.0f }    // End Point
};
 
float range = 100.0f;
 
#else
// The number of control points for this curve
GLint nNumPoints = 3;
 
GLfloat ctrlPoints[3][3][3] = {
    {
        { -4.0f, 0.0f, 4.0f },
        { -2.0f, 4.0f, 4.0f },
        { 4.0f, 0.0f, 4.0f }
    },
 
    { 
        { -4.0f, 0.0f, 0.0f },
        { -2.0f, 4.0f, 0.0f },
        { 4.0f, 0.0f, 0.0f } 
    },
 
    {
        { -4.0f, 0.0f, -4.0f },
        { -2.0f, 4.0f, -4.0f },
        { 4.0f, 0.0f, -4.0f } 
    } 
};
#endif // _1D
 
// This function is used to superimpose the control points over the curve
void DrawPoints(void)
{
    // Set point size larger to make more visible
    glPointSize(5.0f);
 
    // Loop through all control points for this example
    glBegin(GL_POINTS);
#ifdef _1D
    for (int i = 0; i < nNumPoints; i++)
        glVertex2fv(ctrlPoints[i]);
#else
    for (int i = 0; i < nNumPoints; i++)
        for (int j = 0; j < 3; j++)
            glVertex3fv(ctrlPoints[i][j]);
#endif // _1D
 
    glEnd();
}
 
// Called to draw scene
void RenderScene(void)
{
    // Clear the window with current clearing color
    glClear(GL_COLOR_BUFFER_BIT);
 
#ifdef _1D
    // Sets up the bezier
    // This actually only needs to be called once and could go in
    // the setup function
    glMap1f(GL_MAP1_VERTEX_3,    // Type of data generated
        0.0f,                        // Lower u range
        range,                        // Upper u range
        3,                            // Distance between points in the data
        nNumPoints,                    // number of control points
        &ctrlPoints[0][0]);            // array of control points
 
    // Enable the evaluator
    glEnable(GL_MAP1_VERTEX_3);
 
#if _1D
    // Use a line strip to "connect-the-dots"
    glBegin(GL_LINE_STRIP);
    for (int i = 0; i <= range; i++)
    {
        // Evaluate the curve at this point
        glEvalCoord1f((GLfloat)i);
    }
    glEnd();
#else
    // Use higher level functions to map to a grid, then evaluate the
    // entire thing.
    // Put these two functions in to replace above loop
 
    // 100개를 0부터 100까지
    glMapGrid1d(100,0.0,100.0);
 
    // Evaluate the grid, using lines
    glEvalMesh1(GL_LINE,0,100);
#endif
 
    // 단지 지정한 점을 그린다.
    DrawPoints();
 
#else
    // Save the modelview matrix stack
    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
 
    // Rotate the mesh around to make it easier to see
    glRotatef(45.0f, 0.0f, 1.0f, 0.0f);
    glRotatef(60.0f, 1.0f, 0.0f, 0.0f);
 
    // Sets up the Bezier
    // This actually only needs to be called once and could go in
    // the setup function
    glMap2f(GL_MAP2_VERTEX_3,    // Type of data generated
        0.0f,                        // Lower u range
        10.0f,                        // Upper u range
        3,                            // Distance between points in the data
        3,                            // Dimension in u direction (order)
        0.0f,                        // Lover v range
        10.0f,                        // Upper v range
        9,                            // Distance between points in the data
        3,                            // Dimension in v direction (order)
        &ctrlPoints[0][0][0]);        // array of control points
 
    // Enable the evaluator
    glEnable(GL_MAP2_VERTEX_3);
 
    // Use higher level functions to map to a grid, then evaluate the
    // entire thing.
 
    // Map a grid of 10 points from 0 to 10
    glMapGrid2f(10, 0.0f, 10.0f, 10, 0.0f, 10.0f);
 
    // Evaluate the grid, using lines
    glEvalMesh2(GL_LINE, 0, 10, 0, 10);
 
    DrawPoints();
 
    // Restore the modelview matrix
    glPopMatrix();
#endif // _1D
 
    glutSwapBuffers();
}
 
// This function does any needed initialization on the rendering
// context. 
void SetupRC()
{
    // Clear Window to white
    glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
 
    // Draw in Blue
    glColor3f(0.0f, 0.0f, 1.0f);
}
 
///////////////////////////////////////
// Set 2D Projection
void ChangeSize(int w, int h)
{
    // Prevent a divide by zero
    if (h == 0)
        h = 1;
 
    // Set Viewport to window dimensions
    glViewport(0, 0, w, h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
 
#ifdef _1D
    gluOrtho2D(-10.0f, 10.0f, -10.0f, 10.0f);
#else
    glOrtho(-10.0f, 10.0f, -10.0f, 10.0f, -10.0f, 10.0f);
#endif // _1D
 
    // Modelview matrix reset
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
}
 
 
int main(int argc, char* argv[])
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
    glutInitWindowSize(800, 600);
    glutCreateWindow("2D Bezier Curve");
    glutReshapeFunc(ChangeSize);
    glutDisplayFunc(RenderScene);
    SetupRC();
    glutMainLoop();
 
    return 0;
}