git.mutantstargoat.com Git - gba_blender/blob - src/main.c

   1 /*
   2 blender for the Gameboy Advance
   3 Copyright (C) 2021  John Tsiombikas <nuclear@member.fsf.org>
   4
   5 This program is free software: you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation, either version 3 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program.  If not, see <https://www.gnu.org/licenses/>.
  17 */
  18 #include <stdlib.h>
  19 #include <string.h>
  20 #include "gbaregs.h"
  21 #include "timer.h"
  22 #include "keyb.h"
  23 #include "intr.h"
  24 #include "gfx.h"
  25 #include "xgl.h"
  26 #include "polyfill.h"
  27 #include "debug.h"
  28 #include "meshdata.h"
  29
  30 #define MENU_HEIGHT             17
  31 #define TRACK_HEIGHT    18
  32 #define VP_HEIGHT               (160 - MENU_HEIGHT - TRACK_HEIGHT)
  33
  34 static void handle_keys(void);
  35
  36 extern struct { unsigned char r, g, b; } bgimg_cmap[];
  37 extern unsigned char bgimg_pixels[];
  38
  39 static int32_t cam_theta = 0x10000, cam_phi = -0x8000;
  40
  41 static int show_obj = 1, show_del;
  42
  43 #define AXIS0   0x10000
  44 #define AXIS1   0x80000
  45
  46 static struct xvertex gridaxes[] = {
  47         {AXIS0, 0, 0,   0, 0, 0, 92},
  48         {AXIS1, 0, 0,   0, 0, 0, 92},
  49         {-AXIS0, 0, 0,  0, 0, 0, 92},
  50         {-AXIS1, 0, 0,  0, 0, 0, 92},
  51         {0, 0, AXIS0,   0, 0, 0, 93},
  52         {0, 0, AXIS1,   0, 0, 0, 93},
  53         {0, 0, -AXIS0,  0, 0, 0, 93},
  54         {0, 0, -AXIS1,  0, 0, 0, 93},
  55
  56         {0, 0, 0,               0, 0, 0, 92},
  57         {AXIS1, 0, 0,   0, 0, 0, 92},
  58         {0, 0, 0,               0, 0, 0, 92},
  59         {-AXIS1, 0, 0,  0, 0, 0, 92},
  60         {0, 0, 0,               0, 0, 0, 93},
  61         {0, 0, AXIS1,   0, 0, 0, 93},
  62         {0, 0, -0,              0, 0, 0, 93},
  63         {0, 0, -AXIS1,  0, 0, 0, 93},
  64 };
  65
  66 int main(void)
  67 {
  68         int i;
  69         unsigned int nframes = 0, backbuf;
  70         uint16_t *cptr;
  71         unsigned char r, g, b;
  72         unsigned char *fbptr[2], *fb;
  73
  74         intr_init();
  75         reset_msec_timer();
  76         set_intr();
  77
  78         /* mode 4: 240x160 8bpp */
  79         REG_DISPCNT = DISPCNT_BG2 | 4;
  80
  81         fbptr[0] = (unsigned char*)VRAM_LFB_FB0_ADDR;
  82         fbptr[1] = (unsigned char*)VRAM_LFB_FB1_ADDR;
  83
  84         set_bg_color(0xff, 31, 31, 31);
  85
  86         cptr = (uint16_t*)CRAM_BG_ADDR;
  87         for(i=0; i<128; i++) {
  88                 r = bgimg_cmap[i].r >> 3;
  89                 g = bgimg_cmap[i].g >> 3;
  90                 b = bgimg_cmap[i].b >> 3;
  91                 *cptr++ = r | (g << 5) | (b << 10);
  92         }
  93         for(i=0; i<128; i++) {
  94                 r = i / 5 + 6;
  95                 *cptr++ = r | (r << 5) | (r << 10);
  96         }
  97         memcpy(fbptr[0], bgimg_pixels, 240 * 160);
  98         memcpy(fbptr[1], bgimg_pixels, 240 * 160);
  99
 100         xgl_init();
 101         xgl_viewport(0, 0, 240, VP_HEIGHT);
 102         xgl_enable(XGL_LIGHTING);
 103
 104         key_repeat(75, 75, KEY_LEFT | KEY_RIGHT | KEY_DOWN | KEY_UP);
 105
 106         for(;;) {
 107                 handle_keys();
 108
 109                 backbuf = ++nframes & 1;
 110
 111                 fb = fbptr[backbuf] + 240 * MENU_HEIGHT;
 112                 polyfill_framebuffer(fb, 240, VP_HEIGHT);
 113                 memset(fb, 14, 240 * VP_HEIGHT);
 114
 115                 xgl_load_identity();
 116                 xgl_translate(0, 0, 8 << 16);
 117                 xgl_rotate_x(cam_phi);
 118                 xgl_rotate_y(cam_theta);
 119
 120                 if(show_obj) {
 121                         if(cam_theta < X_PI) {
 122                                 xgl_draw(XGL_LINES, gridaxes + 2, 2);   /* -X */
 123                         } else {
 124                                 xgl_draw(XGL_LINES, gridaxes, 2);               /* +X */
 125                         }
 126                         if(cam_theta < X_HPI || cam_theta > (3 * X_HPI)) {
 127                                 xgl_draw(XGL_LINES, gridaxes + 4, 2);   /* +Z */
 128                         } else {
 129                                 xgl_draw(XGL_LINES, gridaxes + 6, 2);   /* -Z */
 130                         }
 131
 132                         if(show_obj == 1) {
 133                                 xgl_draw(XGL_QUADS, cube, sizeof cube / sizeof *cube);
 134                         } else {
 135                                 xgl_draw(XGL_TRIANGLES, suzanne, sizeof suzanne / sizeof *suzanne);
 136                         }
 137
 138                         if(cam_theta < X_PI) {
 139                                 xgl_draw(XGL_LINES, gridaxes, 2);               /* +X */
 140                         } else {
 141                                 xgl_draw(XGL_LINES, gridaxes + 2, 2);   /* -X */
 142                         }
 143                         if(cam_theta < X_HPI || cam_theta > (3 * X_HPI)) {
 144                                 xgl_draw(XGL_LINES, gridaxes + 6, 2);   /* -Z */
 145                         } else {
 146                                 xgl_draw(XGL_LINES, gridaxes + 4, 2);   /* +Z */
 147                         }
 148                 } else {
 149                         xgl_draw(XGL_LINES, gridaxes + 8, 8);
 150                 }
 151
 152                 wait_vblank();
 153                 present(backbuf);
 154         }
 155
 156         return 0;
 157 }
 158
 159 static void handle_keys(void)
 160 {
 161         update_keyb();
 162
 163         if(KEYPRESS(KEY_UP)) {
 164                 cam_phi += 0x2000;
 165                 if(cam_phi > X_HPI) cam_phi = X_HPI;
 166         }
 167         if(KEYPRESS(KEY_DOWN)) {
 168                 cam_phi -= 0x2000;
 169                 if(cam_phi < -X_HPI) cam_phi = -X_HPI;
 170         }
 171         if(KEYPRESS(KEY_LEFT)) {
 172                 cam_theta += 0x2000;
 173                 if(cam_theta > X_2PI) cam_theta -= X_2PI;
 174         }
 175         if(KEYPRESS(KEY_RIGHT)) {
 176                 cam_theta -= 0x2000;
 177                 if(cam_theta < 0) cam_theta += X_2PI;
 178         }
 179         if(KEYPRESS(KEY_RT)) {
 180                 if(++show_obj > 2) show_obj = 0;
 181         }
 182         if(KEYPRESS(KEY_LT)) {
 183                 if(--show_obj < 0) show_obj = 2;
 184         }
 185
 186         if(KEYPRESS(KEY_A)) {
 187                 show_del ^= 1;
 188         }
 189         if(KEYPRESS(KEY_B)) {
 190                 if(show_del) {
 191                         show_obj = 0;
 192                         show_del = 0;
 193                 }
 194         }
 195 }