57 lines
959 B
C
57 lines
959 B
C
#include "common.h"
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void ball_think (ball_t *b)
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{
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uint8_t new_x, new_y;
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if (!b->strength)
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return;
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new_x = (b->x + b->dir_x) >> 8;
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new_y = (b->y + b->dir_y) >> 8;
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/* ball fell out of the field */
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if (new_y >= NUM_ROWS)
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ball_die (b);
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/* bounce in x direction */
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if (check_bounce (new_x, b->y >> 8))
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{
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b->dir_x *= -1; /* invert x vector */
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#if BOUNCE_SLOWDOWN
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if (b->dir_x < 0)
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{
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b->dir_x += BOUNCE_SLOWDOWN;
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} else
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{
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b->dir_x -= BOUNCE_SLOWDOWN;
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}
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#endif
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}
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/* bounce in y direction */
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if (check_bounce (b->x >> 8), new_y)
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{
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b->dir_y *= -1; /* invert y vector */
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#if BOUNCE_SLOWDOWN
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if (b->dir_y < 0)
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{
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b->dir_y += BOUNCE_SLOWDOWN;
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} else
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{
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b->dir_y -= BOUNCE_SLOWDOWN;
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}
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#endif
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}
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}
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void ball_die (ball_t *in_b)
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{
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in_b->strength--;
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/* respawn ball with random direction */
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if (in_b->strength)
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ball_spawn (in_b, (NUM_COLS / 2) << 8, (NUM_ROWS-2) << 8, - random8(), random8(), START_LIFES);
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}
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