dostunnel

annotate src/tunnel.c @ 0:c525cfbfd4a2

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initial commit
author John Tsiombikas <nuclear@member.fsf.org>
date Fri, 15 Mar 2013 16:46:41 +0200
parents
children 5d7f784002b0
rev   line source
nuclear@0 1 #include <stdio.h>
nuclear@0 2 #include <stdlib.h>
nuclear@0 3 #include <string.h>
nuclear@0 4 #include <math.h>
nuclear@0 5 #include <conio.h>
nuclear@0 6 #include "wvga.h"
nuclear@0 7 #include "texture.h"
nuclear@0 8 #include "palman.h"
nuclear@0 9
nuclear@0 10 #ifndef M_PI
nuclear@0 11 #define M_PI 3.14159265
nuclear@0 12 #endif
nuclear@0 13
nuclear@0 14 #define WIDTH 320
nuclear@0 15 #define HEIGHT 200
nuclear@0 16
nuclear@0 17 int init(void);
nuclear@0 18 void cleanup(void);
nuclear@0 19 void display(void);
nuclear@0 20 int calc_tunnel_mapping(void);
nuclear@0 21
nuclear@0 22 static unsigned char *fbuf;
nuclear@0 23 static struct texture *tex;
nuclear@0 24 static int colrange;
nuclear@0 25
nuclear@0 26 static char *tex_fname;
nuclear@0 27
nuclear@0 28 static unsigned long *umap, *vmap;
nuclear@0 29
nuclear@0 30 static unsigned long frames;
nuclear@0 31 static unsigned long start_time;
nuclear@0 32
nuclear@0 33 int main(int argc, char **argv)
nuclear@0 34 {
nuclear@0 35 if(argc > 1) {
nuclear@0 36 tex_fname = argv[1];
nuclear@0 37 }
nuclear@0 38
nuclear@0 39 if(init() == -1) {
nuclear@0 40 return 1;
nuclear@0 41 }
nuclear@0 42
nuclear@0 43 while(!kbhit()) {
nuclear@0 44 display();
nuclear@0 45 }
nuclear@0 46 cleanup();
nuclear@0 47 return 0;
nuclear@0 48 }
nuclear@0 49
nuclear@0 50 int init(void)
nuclear@0 51 {
nuclear@0 52 int i;
nuclear@0 53 struct palm_color *pal;
nuclear@0 54
nuclear@0 55 if(!(fbuf = malloc(WIDTH * HEIGHT))) {
nuclear@0 56 fprintf(stderr, "failed to allocate framebuffer\n");
nuclear@0 57 return -1;
nuclear@0 58 }
nuclear@0 59
nuclear@0 60 if(calc_tunnel_mapping() == -1) {
nuclear@0 61 fprintf(stderr, "failed to precalc tunnel mapping\n");
nuclear@0 62 return 1;
nuclear@0 63 }
nuclear@0 64
nuclear@0 65 if(tex_fname) {
nuclear@0 66 if(!(tex = load_texture(tex_fname))) {
nuclear@0 67 fprintf(stderr, "failed to load texture: %s\n", tex_fname);
nuclear@0 68 free(fbuf);
nuclear@0 69 return -1;
nuclear@0 70 }
nuclear@0 71
nuclear@0 72 } else {
nuclear@0 73 fprintf(stderr, "FOO\n");
nuclear@0 74 return -1;
nuclear@0 75 }
nuclear@0 76
nuclear@0 77 set_video_mode(0x13);
nuclear@0 78
nuclear@0 79 palm_build();
nuclear@0 80 get_texture_pixels(tex);
nuclear@0 81
nuclear@0 82 pal = palm_palette();
nuclear@0 83 for(i=0; i<palm_palette_size(); i++) {
nuclear@0 84 set_pal_entry(i, pal[i].r, pal[i].g, pal[i].b);
nuclear@0 85 }
nuclear@0 86 colrange = palm_color_range();
nuclear@0 87
nuclear@0 88 return 0;
nuclear@0 89 }
nuclear@0 90
nuclear@0 91 void cleanup(void)
nuclear@0 92 {
nuclear@0 93 free_texture(tex);
nuclear@0 94 free(fbuf);
nuclear@0 95 set_video_mode(0x3);
nuclear@0 96 }
nuclear@0 97
nuclear@0 98 void display(void)
nuclear@0 99 {
nuclear@0 100 static unsigned long msec;
nuclear@0 101
nuclear@0 102 unsigned int i;
nuclear@0 103 unsigned char voffs = msec >> 3;
nuclear@0 104 unsigned char uoffs = msec >> 6;
nuclear@0 105
nuclear@0 106 unsigned char *fbptr = fbuf;
nuclear@0 107 unsigned long *uptr = umap;
nuclear@0 108 unsigned long *vptr = vmap;
nuclear@0 109
nuclear@0 110 for(i=0; i<64000; i++) {
nuclear@0 111 unsigned long u = *uptr++;
nuclear@0 112 unsigned long v = *vptr++;
nuclear@0 113 unsigned long tx = ((((unsigned long)(u - uoffs) << 3) & 0xff) * tex->width) >> 8;
nuclear@0 114 unsigned long ty = (((unsigned long)(v + voffs) & 0xff) * tex->height) >> 8;
nuclear@0 115
nuclear@0 116 unsigned long base = tex->pixels[ty * tex->width + tx];
nuclear@0 117 long zcue_shift = colrange - (v >> 6);
nuclear@0 118 if(zcue_shift < 0) {
nuclear@0 119 zcue_shift = 0;
nuclear@0 120 }
nuclear@0 121 *fbptr++ = (unsigned char)(base + zcue_shift);
nuclear@0 122 }
nuclear@0 123
nuclear@0 124 copy_frame(fbuf);
nuclear@0 125 msec += 33;
nuclear@0 126 }
nuclear@0 127
nuclear@0 128 int calc_tunnel_mapping(void)
nuclear@0 129 {
nuclear@0 130 int i, j;
nuclear@0 131 unsigned long *uptr, *vptr;
nuclear@0 132 float diag_dist = sqrt(1.33333 * 1.33333 + 1.0);
nuclear@0 133
nuclear@0 134 if(!(umap = malloc(WIDTH * HEIGHT * sizeof *umap))) {
nuclear@0 135 return -1;
nuclear@0 136 }
nuclear@0 137 if(!(vmap = malloc(WIDTH * HEIGHT * sizeof *umap))) {
nuclear@0 138 free(umap);
nuclear@0 139 return -1;
nuclear@0 140 }
nuclear@0 141
nuclear@0 142 uptr = umap;
nuclear@0 143 vptr = vmap;
nuclear@0 144
nuclear@0 145 for(i=0; i<HEIGHT; i++) {
nuclear@0 146 for(j=0; j<WIDTH; j++) {
nuclear@0 147 float x = ((float)j / WIDTH * 2.0 - 1.0) * 1.33333;
nuclear@0 148 float y = (float)i / HEIGHT * 2.0 - 1.0;
nuclear@0 149 float angle, z, dist;
nuclear@0 150
nuclear@0 151 if(fabs(x) > 0.00001) {
nuclear@0 152 angle = atan2(y, x) + M_PI;
nuclear@0 153 } else {
nuclear@0 154 angle = y < 0.0 ? M_PI / 2.0 : 3.0 * M_PI / 2.0;
nuclear@0 155 }
nuclear@0 156 dist = sqrt(x * x + y * y);
nuclear@0 157 z = 2.0 / dist;
nuclear@0 158
nuclear@0 159 *uptr++ = (unsigned int)(angle * 0.5 / M_PI * 255.0);
nuclear@0 160 *vptr++ = (unsigned int)(z * 255.0);
nuclear@0 161 }
nuclear@0 162 }
nuclear@0 163 return 0;
nuclear@0 164 }