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#include "SDL.h"
#include "SDL_opengl.h"
#include "ball.h"
typedef struct {
Coord_t coord;
GLfloat w, h;
GLfloat r, g, b;
GLfloat xv, yv, zv;
GLfloat rotate;
} Ball_t;
static Ball_t ball;
static GLuint ball_texture;
void
GLPong_BallDraw(void) {
glLoadIdentity();
glBindTexture(GL_TEXTURE_2D, ball_texture);
glEnable(GL_TEXTURE_2D);
glColor3f(ball.r, ball.g, ball.b);
glTranslatef(ball.coord.x, ball.coord.y, ball.coord.z);
glBegin(GL_QUADS);
glTexCoord2f(0.0f, 1.0f); glVertex2f(ball.w, ball.h); /* Lower Left */
glTexCoord2f(1.0f, 1.0f); glVertex2f(0.0f, ball.h); /* Lower Right */
glTexCoord2f(1.0f, 0.0f); glVertex2f(0.0f, 0.0f); /* Upper Right */
glTexCoord2f(0.0f, 0.0f); glVertex2f(ball.w, 0.0f); /* Upper Left */
glEnd();
glDisable(GL_TEXTURE_2D);
#ifdef DEBUG
/* Lower Left */
glLoadIdentity();
glColor3f(1.0f, 0.0f, 0.0f);
glTranslatef(ball.coord.x, ball.coord.y, ball.coord.z);
glBegin(GL_POINTS);
glVertex3f(0.0f, 0.0f, 0.0f);
glEnd();
/* Lower Right */
glLoadIdentity();
glTranslatef(ball.coord.x + ball.w, ball.coord.y, ball.coord.z);
glBegin(GL_POINTS);
glVertex3f(0.0f, 0.0f, 0.0f);
glEnd();
/* Top Right */
glLoadIdentity();
glTranslatef(ball.coord.x + ball.w, ball.coord.y + ball.h, ball.coord.z);
glBegin(GL_POINTS);
glVertex3f(0.0f, 0.0f, 0.0f);
glEnd();
/* Top Left */
glLoadIdentity();
glTranslatef(ball.coord.x, ball.coord.y + ball.h, ball.coord.z);
glBegin(GL_POINTS);
glVertex3f(0.0f, 0.0f, 0.0f);
glEnd();
#endif
glLoadIdentity();
glTranslatef(0.0f, 0.0f, ball.coord.z);
glCallList(box);
}
void
GLPong_BallInit(GLuint texture) {
ball.w = 0.5f;
ball.h = 0.5f;
ball.coord.x = -(ball.w / 2);
ball.coord.y = -(ball.h / 2);
ball.coord.z = GLPONG_FRONT_Z;
ball.r = 1.0f;
ball.g = 0.0f;
ball.b = 0.0f;
ball.xv = 0.02f;
ball.yv = 0.01f;
ball.zv = -0.05f;
ball_texture = texture;
}
void
GLPong_BallMove(void) {
ball.coord.x += ball.xv;
if (ball.coord.x > 1.0f) {
ball.coord.x = 1.0f;
ball.xv = -ball.xv;
} else if (ball.coord.x + ball.w < -1.0f) {
ball.coord.x = -1.0f - ball.w;
ball.xv = -ball.xv;
}
ball.coord.y += ball.yv;
if (ball.coord.y > 0.5f) {
ball.coord.y = 0.5f;
ball.yv = -ball.yv;
} else if (ball.coord.y + ball.h < -0.5f) {
ball.coord.y = -0.5f - ball.h;
ball.yv = -ball.yv;
}
ball.coord.z += ball.zv;
if (ball.coord.z < GLPONG_BACK_Z) {
ball.coord.z = GLPONG_BACK_Z;
ball.zv = -ball.zv;
} else if (ball.coord.z > GLPONG_FRONT_Z) {
ball.coord.z = GLPONG_FRONT_Z;
ball.zv = -ball.zv;
}
}
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