RogueLife/src/anim.c

#include "anim.h"
#include <gint/display.h>

/* List of animations (and directional animations). */
#define NORMAL_ANIM(name) \
    extern anim_frame_t name[];
#define DIRECTIONAL_ANIM(name) \
    extern anim_frame_t name ## _up[]; \
    extern anim_frame_t name ## _right[]; \
    extern anim_frame_t name ## _down[]; \
    extern anim_frame_t name ## _left[]; \
    anim_frame_t *name[4] = { \
        name ## _up, name ## _right, name ## _down, name ## _left };

DIRECTIONAL_ANIM(anim_player_idle);
DIRECTIONAL_ANIM(anim_player_attack);
DIRECTIONAL_ANIM(anim_swing);

/* Animation functions. */

fixed_t (anim_duration)(anim_frame_t const *first_frame)
{
    anim_frame_t const *frame = first_frame;
    int ms = 0;
    int i = 0;

    while(frame == first_frame + i) {
        ms += frame->duration;
        frame = frame->next;
        i++;
    }

    return fix(ms) / 1000;
}

void anim_frame_render(int x, int y, anim_frame_t const *frame)
{
    dsubimage(x - frame->cx, y - frame->cy, frame->sheet,
        frame->x, frame->y, frame->w, frame->h, DIMAGE_NONE);
}

void anim_state_update(anim_state_t *state, fixed_t dt)
{
    if(!state->frame) return;

    state->elapsed += fround(dt * 1000);
    if(state->elapsed < state->frame->duration) return;

    /* Switch to next frame */
    state->elapsed = 0;
    anim_frame_t const *next = state->frame->next;
    if(next)
        state->frame = next;
}