cscg22-gearboy

CSCG 2022 Challenge 'Gearboy'
git clone https://git.sinitax.com/sinitax/cscg22-gearboy
Log | Files | Refs | sfeed.txt

metasprites.c (3782B)

      1#include <gbdk/platform.h>
      2#include <gbdk/metasprites.h>
      3
      4#include <stdint.h>
      5
      6// During build, png2asset metasprite conversion will write output to: obj/<platform ext>/res/
      7//  Makefile adds part of that path as an include when compiling. Example: -Iobj/gb
      8#include <res/sprite.h>
      9
     10
     11const unsigned char pattern[] = {0x80,0x80,0x40,0x40,0x20,0x20,0x10,0x10,0x08,0x08,0x04,0x04,0x02,0x02,0x01,0x01};
     12
     13joypads_t joypads;
     14
     15#define ACC_X 1
     16#define ACC_Y 2
     17
     18// The metasprite will be built starting with hardware sprite zero (the first)
     19#define SPR_NUM_START 0
     20
     21// Metasprite tiles are loaded into VRAM starting at tile number 0 
     22#define TILE_NUM_START 0
     23
     24// sprite coords
     25uint16_t PosX, PosY;
     26int16_t SpdX, SpdY;
     27uint8_t PosF;
     28uint8_t hide, jitter;
     29uint8_t idx;
     30
     31// main funxction
     32void main(void) {
     33    DISPLAY_OFF;
     34
     35    // Fill the screen background with a single tile pattern
     36    fill_bkg_rect(0, 0, DEVICE_SCREEN_WIDTH, DEVICE_SCREEN_HEIGHT, 0);
     37
     38    // set tile data for background
     39    set_bkg_data(0, 1, pattern);
     40
     41    // Load metasprite tile data into VRAM
     42    set_sprite_data(TILE_NUM_START, sizeof(sprite_tiles) >> 4, sprite_tiles);
     43
     44    // show bkg and sprites
     45    SHOW_BKG; SHOW_SPRITES;
     46
     47    // Check what size hardware sprite the metasprite is using (from sprite.h)
     48    #if sprite_TILE_H == 16
     49        SPRITES_8x16;
     50    #else
     51        SPRITES_8x8;
     52    #endif
     53    DISPLAY_ON;
     54
     55    // init 1 joypad
     56    joypad_init(1, &joypads);
     57 
     58    // Set initial position, zero out speed
     59    PosX = PosY = 96 << 4;
     60    SpdX = SpdY = 0;
     61
     62    hide = 0; jitter = 0; idx = 0;
     63
     64    while(1) {        
     65        // poll joypads
     66        joypad_ex(&joypads);
     67        
     68        PosF = 0;
     69        // game object
     70        if (joypads.joy0 & J_UP) {
     71            SpdY -= 2;
     72            if (SpdY < -32) SpdY = -32;
     73            PosF |= ACC_Y;
     74        } else if (joypads.joy0 & J_DOWN) {
     75            SpdY += 2;
     76            if (SpdY > 32) SpdY = 32;
     77            PosF |= ACC_Y;
     78        }
     79
     80        if (joypads.joy0 & J_LEFT) {
     81            SpdX -= 2;
     82            if (SpdX < -32) SpdX = -32;
     83            PosF |= ACC_X;
     84        } else if (joypads.joy0 & J_RIGHT) {
     85            SpdX += 2;
     86            if (SpdX > 32) SpdX = 32;
     87            PosF |= ACC_X;
     88        }
     89
     90
     91        // Press A button to show/hide metasprite
     92        if ((joypads.joy0 & J_A) && (!jitter)) {
     93            hide = (!hide);
     94            jitter = 20;
     95        }
     96
     97        // Press B button to cycle through metasprite animations
     98        if ((joypads.joy0 & J_B) && (!jitter) && (!hide)) {
     99            idx++; if (idx >= (sizeof(sprite_metasprites) >> 1)) idx = 0;
    100            jitter = 10;
    101        }
    102
    103        // Hide/Animate/Flip input throttling
    104        if (jitter) jitter--;
    105
    106        PosX += SpdX, PosY += SpdY; 
    107
    108        uint8_t hiwater = 0;
    109	
    110        // Hide the metasprite or move it
    111        if (hide)
    112            hide_metasprite(sprite_metasprites[idx], SPR_NUM_START);
    113        else
    114            hiwater = move_metasprite(sprite_metasprites[idx], TILE_NUM_START, SPR_NUM_START, (PosX >> 4), (PosY >> 4));
    115
    116        // Hide rest of the hardware sprites, because amount of sprites differ between animation frames.
    117        hide_sprites_range(hiwater, MAX_HARDWARE_SPRITES);        
    118
    119        // Y Axis: update velocity (reduce speed) if no U/D button pressed
    120        if (!(PosF & ACC_Y)) {
    121            if (SpdY != 0) {
    122                if (SpdY < 0) SpdY++;
    123                else SpdY --;
    124            }
    125        }
    126
    127        // X Axis: update velocity (reduce speed) if no L/R button pressed
    128        if (!(PosF & ACC_X)) {
    129            if (SpdX != 0) {
    130                if (SpdX < 0) SpdX++;
    131                else SpdX --;
    132            }
    133        }
    134
    135        // wait for VBlank to slow down everything and reduce cpu use when idle
    136        wait_vbl_done();
    137    }
    138}
    139