mirror of
https://github.com/deater/dos33fsprogs.git
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tfv: complete conversion to fixed point
This commit is contained in:
Vince Weaver
parent
762793f06d
commit
373a289ca3
@ -8,7 +8,7 @@ struct fixed_type {
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};
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void double_to_fixed(double d, struct fixed_type *f) {
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static void double_to_fixed(double d, struct fixed_type *f) {
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int temp;
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@ -18,19 +18,24 @@ void double_to_fixed(double d, struct fixed_type *f) {
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f->f=temp&0xff;
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printf("%lf=%02x.%02x\n",d,f->i,f->f);
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}
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void fixed_to_double(struct fixed_type *f, double *d) {
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static void print_fixed(struct fixed_type *f) {
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printf("%02X.%02X",f->i,f->f);
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}
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static void fixed_to_double(struct fixed_type *f, double *d) {
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*d=f->i;
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*d+=((double)(f->f))/256.0;
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printf("(%02x.%02x)=%lf\n",f->i,f->f,*d);
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// printf("(%02x.%02x)=%lf\n",f->i,f->f,*d);
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}
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void fixed_add(struct fixed_type *x, struct fixed_type *y, struct fixed_type *z) {
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static void fixed_add(struct fixed_type *x, struct fixed_type *y, struct fixed_type *z) {
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int carry;
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short sum;
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@ -44,7 +49,7 @@ void fixed_add(struct fixed_type *x, struct fixed_type *y, struct fixed_type *z)
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z->i=x->i+y->i+carry;
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}
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void fixed_mul(struct fixed_type *x, struct fixed_type *y, struct fixed_type *z) {
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static void fixed_mul(struct fixed_type *x, struct fixed_type *y, struct fixed_type *z) {
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int a,b,c;
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@ -52,7 +57,7 @@ void fixed_mul(struct fixed_type *x, struct fixed_type *y, struct fixed_type *z)
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b=((y->i)<<8)+(y->f);
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c=a*b;
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printf("%x %x %x\n",a,b,c);
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// printf("%x %x %x\n",a,b,c);
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c>>=8;
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@ -67,54 +72,146 @@ int main(int argc, char **argv) {
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double d,c;
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int i;
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printf("Testing positive:\n");
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printf("\tConverting 4.25 to fixed: ");
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double_to_fixed(4.25,&f);
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fixed_to_double(&f,&d);
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print_fixed(&f);
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printf(" %lf\n",d);
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printf("\tConverting 3.14159265358979 to fixed: ");
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double_to_fixed(3.14159265358979,&f);
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fixed_to_double(&f,&d);
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print_fixed(&f);
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printf(" %lf\n",d);
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printf("\tConverting 127.333333333 to fixed: ");
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double_to_fixed(127.333333333,&f);
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fixed_to_double(&f,&d);
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print_fixed(&f);
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printf(" %lf\n",d);
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printf("\tConverting 50.9 to fixed: ");
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double_to_fixed(50.9,&f);
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fixed_to_double(&f,&d);
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print_fixed(&f);
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printf(" %lf\n",d);
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printf("Testing negative:\n");
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printf("\tConverting -4.25 to fixed: ");
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double_to_fixed(-4.25,&f);
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fixed_to_double(&f,&d);
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print_fixed(&f);
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printf(" %lf\n",d);
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printf("\tConverting -3.14159265358979 to fixed: ");
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double_to_fixed(-3.14159265358979,&f);
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fixed_to_double(&f,&d);
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print_fixed(&f);
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printf(" %lf\n",d);
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printf("\tConverting -127.333333333 to fixed: ");
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double_to_fixed(-127.333333333,&f);
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fixed_to_double(&f,&d);
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print_fixed(&f);
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printf(" %lf\n",d);
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printf("\tConverting -50.9 to fixed: ");
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double_to_fixed(-50.9,&f);
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fixed_to_double(&f,&d);
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print_fixed(&f);
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printf(" %lf\n",d);
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printf("Testing addition:\n");
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printf("\t2.75 + 12.75 = %lf, ",2.75+12.75);
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double_to_fixed(2.75,&fa);
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double_to_fixed(12.75,&fb);
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fixed_add(&fa,&fb,&fc);
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fixed_to_double(&fc,&c);
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print_fixed(&fc);
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printf(" %lf\n",c);
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printf("\t-1.25 + -1.75 = %lf, ",-1.25 + -1.75);
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double_to_fixed(-1.25,&fa);
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double_to_fixed(-1.75,&fb);
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fixed_add(&fa,&fb,&fc);
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fixed_to_double(&fc,&c);
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print_fixed(&fc);
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printf(" %lf\n",c);
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printf("\t5.0 + -4.1 = %lf, ",5.0 + -4.1);
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double_to_fixed(5.0,&fa);
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double_to_fixed(-4.1,&fb);
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fixed_add(&fa,&fb,&fc);
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fixed_to_double(&fc,&c);
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print_fixed(&fc);
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printf(" %lf\n",c);
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printf("Testing multiplication:\n");
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printf("\t2.5 * 2.5 = %lf, ",2.5 * 2.5);
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double_to_fixed(2.5,&fa);
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double_to_fixed(2.5,&fb);
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fixed_mul(&fa,&fb,&fc);
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fixed_to_double(&fc,&c);
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print_fixed(&fc);
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printf(" %lf\n",c);
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printf("\t-1.1 * -1.1 = %lf, ",-1.1 * -1.1);
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double_to_fixed(-1.1,&fa);
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double_to_fixed(-1.1,&fb);
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fixed_mul(&fa,&fb,&fc);
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fixed_to_double(&fc,&c);
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print_fixed(&fc);
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printf(" %lf\n",c);
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printf("\t-2 * 5 = %lf, ",-2.0 * 5.0);
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double_to_fixed(-2.0,&fa);
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double_to_fixed(5.0,&fb);
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fixed_mul(&fa,&fb,&fc);
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fixed_to_double(&fc,&c);
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print_fixed(&fc);
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printf(" %lf\n",c);
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printf("\t13.2 * -0.5 = %lf, ",13.2 * -0.5);
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double_to_fixed(13.2,&fa);
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double_to_fixed(-0.5,&fb);
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fixed_mul(&fa,&fb,&fc);
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fixed_to_double(&fc,&c);
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print_fixed(&fc);
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printf(" %lf\n",c);
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for(i=0;i<16;i++) {
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d=sin((double)i/16.0*3.1415926535897932384*2.0);
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double_to_fixed(d/8.0,&fa);
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}
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double space_z=0.5;
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double coach_z;
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double horizon=-2.0;
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printf("horizontal_scale_lookup:\n");
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for(space_z=0.5;space_z<7.5;space_z+=1.0) {
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printf("{");
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for(i=8;i<40;i+=2) {
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coach_z=space_z/((double)i-horizon);
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double_to_fixed(coach_z,&fa);
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if (fa.i!=0) {
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printf("CRITICAL ERROR TOP NOT 0\n");
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}
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printf("0x%02X,",fa.f);
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}
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printf("},\n");
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}
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for(coach_z=-1.0;coach_z<1.0;coach_z+=0.1) {
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double_to_fixed(coach_z,&fa);
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printf("%lf\t%02X,%02X\n",coach_z,fa.i,fa.f);
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}
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return 0;
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}
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@ -67,68 +67,42 @@ static int screen_x, screen_y;
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static char angle=0;
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#if 1
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struct fixed_type {
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char i;
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unsigned char f;
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};
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// 1 = use reduced fixed point
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// 0 = use fancy hi-res floating point
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#if 1
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#if 0
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// map coordinates
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struct fixed_type speed = {0,0};
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// step for points in space between two pixels on a horizontal line
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struct fixed_type line_dx = {0,0};
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struct fixed_type line_dy = {0,0};
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// current space position
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// height of the camera above the plane
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struct fixed_type space_z= {0x04,0x80}; // 4.5;
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struct fixed_type BETA = {0xff,0x80}; // -0.5;
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#else
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// Speed
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#define SPEED_STOPPED 0
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static unsigned char speed=SPEED_STOPPED; // 0..4, with 0=stopped
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// map coordinates
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static double double_cx;
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static double double_cy;
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static struct fixed_type cx = {0,0};
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static struct fixed_type cy = {0,0};
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static struct fixed_type dx;
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static struct fixed_type dy;
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#define SPEED_STOPPED 0
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static unsigned char speed=SPEED_STOPPED; // 0..4, with 0=stopped
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// the distance and horizontal scale of the line we are drawing
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static double double_distance=0;
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static double double_horizontal_scale=0;
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static struct fixed_type distance;
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static struct fixed_type horizontal_scale;
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// step for points in space between two pixels on a horizontal line
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static double line_dx=0;
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static double line_dy=0;
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// current space position
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static double double_space_x,double_space_y;
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static struct fixed_type space_x;
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static struct fixed_type space_y;
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// height of the camera above the plane
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static double space_z=4.5;
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static double BETA=-0.5;
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static struct fixed_type space_z= {0x04,0x80}; // 4.5;
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static struct fixed_type BETA = {0xff,0x80}; // -0.5;
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static struct fixed_type factor;
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#endif
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static struct fixed_type fixed_temp;
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static int horizon=-2; // number of pixels line 0 is below the horizon
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static double SCALE=16.0;
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static struct fixed_type scale={0x14,0x00}; // 20.0
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#define ANGLE_STEPS 16
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@ -173,38 +147,27 @@ static struct fixed_type fixed_sin_scale[ANGLE_STEPS]={
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{0xff,0xf4},
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};
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static double sin_table[ANGLE_STEPS]={
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0.000000,
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0.382683,
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0.707107,
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0.923880,
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1.000000,
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0.923880,
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0.707107,
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0.382683,
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0.000000,
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-0.382683,
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-0.707107,
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-0.923880,
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-1.000000,
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-0.923880,
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-0.707107,
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-0.382683,
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static unsigned char horizontal_lookup[7][16] = {
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{0x0C,0x0A,0x09,0x08,0x07,0x06,0x05,0x05,0x04,0x04,0x04,0x04,0x03,0x03,0x03,0x03,},
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{0x26,0x20,0x1B,0x18,0x15,0x13,0x11,0x10,0x0E,0x0D,0x0C,0x0C,0x0B,0x0A,0x0A,0x09,},
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{0x40,0x35,0x2D,0x28,0x23,0x20,0x1D,0x1A,0x18,0x16,0x15,0x14,0x12,0x11,0x10,0x10,},
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{0x59,0x4A,0x40,0x38,0x31,0x2C,0x28,0x25,0x22,0x20,0x1D,0x1C,0x1A,0x18,0x17,0x16,},
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{0x73,0x60,0x52,0x48,0x40,0x39,0x34,0x30,0x2C,0x29,0x26,0x24,0x21,0x20,0x1E,0x1C,},
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{0x8C,0x75,0x64,0x58,0x4E,0x46,0x40,0x3A,0x36,0x32,0x2E,0x2C,0x29,0x27,0x25,0x23,},
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{0xA6,0x8A,0x76,0x68,0x5C,0x53,0x4B,0x45,0x40,0x3B,0x37,0x34,0x30,0x2E,0x2B,0x29,},
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};
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static double our_sin(unsigned char angle) {
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return sin_table[angle&0xf];
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}
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static double our_cos(unsigned char angle) {
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return sin_table[(angle+4)&0xf];
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}
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double fixed_to_double(struct fixed_type *f) {
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static void fixed_to_double(struct fixed_type *f, double *d) {
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double out;
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out=f->i;
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out+=((double)(f->f))/256.0;
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return out;
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*d=f->i;
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*d+=((double)(f->f))/256.0;
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}
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static void fixed_add(struct fixed_type *x, struct fixed_type *y, struct fixed_type *z) {
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@ -221,16 +184,16 @@ static void fixed_add(struct fixed_type *x, struct fixed_type *y, struct fixed_t
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z->i=x->i+y->i+carry;
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}
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static void double_to_fixed(double d, struct fixed_type *f) {
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int temp;
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temp=d*256;
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f->i=(temp>>8)&0xff;
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f->f=temp&0xff;
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}
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//static void double_to_fixed(double d, struct fixed_type *f) {
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//
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// int temp;
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//
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// temp=d*256;
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//
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// f->i=(temp>>8)&0xff;
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//
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// f->f=temp&0xff;
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//}
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static void fixed_mul(struct fixed_type *x, struct fixed_type *y, struct fixed_type *z) {
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@ -272,16 +235,28 @@ void draw_background_mode7(void) {
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color_equals(COLOR_GREY);
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hlin_double(ram[DRAW_PAGE], 0, 40, 6);
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// fixed_to_double(&space_z,&double_space_z);
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// double_factor=double_space_z*double_BETA;
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fixed_mul(&space_z,&BETA,&factor);
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printf("spacez=%lf beta=%lf factor=%lf\n",
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fixed_to_double(&space_z),
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fixed_to_double(&BETA),
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fixed_to_double(&factor));
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for (screen_y = 8; screen_y < LOWRES_H; screen_y+=2) {
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// then calculate the horizontal scale, or the distance between
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// space points on this horizontal line
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double_horizontal_scale = space_z / (screen_y + horizon);
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double_to_fixed(double_horizontal_scale,&horizontal_scale);
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// double_horizontal_scale = double_space_z / (screen_y + horizon);
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// double_to_fixed(double_horizontal_scale,&horizontal_scale);
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horizontal_scale.i=0;
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horizontal_scale.f=horizontal_lookup[space_z.i&0xf][(screen_y-8)/2];
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// calculate the distance of the line we are drawing
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double_distance = double_horizontal_scale * SCALE;
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double_to_fixed(double_distance,&distance);
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fixed_mul(&horizontal_scale,&scale,&distance);
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//fixed_to_double(&distance,&double_distance);
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// printf("Distance=%lf, horizontal-scale=%lf\n",
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// distance,horizontal_scale);
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@ -296,24 +271,30 @@ void draw_background_mode7(void) {
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dy.f=fixed_sin[(angle+4)&0xf].f; // cos()
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fixed_mul(&dy,&horizontal_scale,&dy);
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fixed_to_double(&dx,&line_dx);
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fixed_to_double(&dy,&line_dy);
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// Move camera back a bit
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double factor;
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factor=space_z*BETA;
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// calculate the starting position
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double_space_x = double_cx +
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((double_distance+factor) * our_cos(angle)) -
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(LOWRES_W/2 * line_dx);
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double_space_y = double_cy +
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((double_distance+factor) * our_sin(angle)) -
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(LOWRES_W/2 * line_dy);
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//double_space_x =(double_distance+double_factor);
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fixed_add(&distance,&factor,&space_x);
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// double_to_fixed(double_space_x,&space_x);
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fixed_temp.i=fixed_sin[(angle+4)&0xf].i; // cos
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fixed_temp.f=fixed_sin[(angle+4)&0xf].f; // cos
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fixed_mul(&space_x,&fixed_temp,&space_x);
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fixed_add(&space_x,&cx,&space_x);
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fixed_temp.i=0xec; // -20 (LOWRES_W/2)
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fixed_temp.f=0;
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fixed_mul(&fixed_temp,&dx,&fixed_temp);
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fixed_add(&space_x,&fixed_temp,&space_x);
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double_to_fixed(double_space_x,&space_x);
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double_to_fixed(double_space_y,&space_y);
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fixed_add(&distance,&factor,&space_y);
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// double_space_y =(double_distance+double_factor);
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// double_to_fixed(double_space_y,&space_y);
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fixed_temp.i=fixed_sin[angle&0xf].i;
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fixed_temp.f=fixed_sin[angle&0xf].f;
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fixed_mul(&space_y,&fixed_temp,&space_y);
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fixed_add(&space_y,&cy,&space_y);
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fixed_temp.i=0xec; // -20 (LOWRES_W/2)
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fixed_temp.f=0;
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fixed_mul(&fixed_temp,&dy,&fixed_temp);
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fixed_add(&space_y,&fixed_temp,&space_y);
|
||||
|
||||
// go through all points in this screen line
|
||||
for (screen_x = 0; screen_x < LOWRES_W-1; screen_x++) {
|
||||
@ -365,20 +346,20 @@ int flying(void) {
|
||||
if ((ch=='w') || (ch==APPLE_UP)) {
|
||||
if (shipy>16) {
|
||||
shipy-=2;
|
||||
space_z+=1;
|
||||
space_z.i++;
|
||||
}
|
||||
|
||||
printf("Z=%lf\n",space_z);
|
||||
printf("Z=%x.%x\n",space_z.i,space_z.f);
|
||||
}
|
||||
if ((ch=='s') || (ch==APPLE_DOWN)) {
|
||||
if (shipy<28) {
|
||||
shipy+=2;
|
||||
space_z-=1;
|
||||
space_z.i--;
|
||||
}
|
||||
else {
|
||||
draw_splash=10;
|
||||
}
|
||||
printf("Z=%lf\n",space_z);
|
||||
printf("Z=%x.%x\n",space_z.i,space_z.f);
|
||||
}
|
||||
if ((ch=='a') || (ch==APPLE_LEFT)) {
|
||||
if (turning>0) {
|
||||
@ -403,18 +384,18 @@ int flying(void) {
|
||||
|
||||
}
|
||||
|
||||
if (ch=='h') {
|
||||
horizon--;
|
||||
if (horizon<-4) horizon=4;
|
||||
// if (ch=='h') {
|
||||
// horizon--;
|
||||
// if (horizon<-4) horizon=4;
|
||||
//
|
||||
// printf("horizon=%d\n",horizon);
|
||||
// }
|
||||
|
||||
printf("horizon=%d\n",horizon);
|
||||
}
|
||||
|
||||
if (ch=='y') {
|
||||
if (SCALE==20) SCALE=16;
|
||||
else SCALE=20;
|
||||
printf("SCALE=%lf\n",SCALE);
|
||||
}
|
||||
// if (ch=='y') {
|
||||
// if (SCALE==20) SCALE=16;
|
||||
// else SCALE=20;
|
||||
// printf("SCALE=%lf\n",SCALE);
|
||||
// }
|
||||
|
||||
// increase speed
|
||||
if (ch=='z') {
|
||||
@ -445,8 +426,6 @@ int flying(void) {
|
||||
fixed_add(&cx,&dx,&cx);
|
||||
fixed_add(&cy,&dy,&cy);
|
||||
}
|
||||
fixed_to_double(&cx,&double_cx);
|
||||
fixed_to_double(&cy,&double_cy);
|
||||
|
||||
}
|
||||
|
||||
@ -457,7 +436,7 @@ int flying(void) {
|
||||
grsim_put_sprite(splash_forward,
|
||||
SHIPX+1,shipy+9);
|
||||
}
|
||||
grsim_put_sprite(shadow_forward,SHIPX+3,31+space_z);
|
||||
grsim_put_sprite(shadow_forward,SHIPX+3,31+space_z.i);
|
||||
grsim_put_sprite(ship_forward,SHIPX,shipy);
|
||||
}
|
||||
if (turning<0) {
|
||||
@ -468,7 +447,7 @@ int flying(void) {
|
||||
grsim_put_sprite(splash_left,
|
||||
SHIPX+1,36);
|
||||
}
|
||||
grsim_put_sprite(shadow_left,SHIPX+3,31+space_z);
|
||||
grsim_put_sprite(shadow_left,SHIPX+3,31+space_z.i);
|
||||
grsim_put_sprite(ship_left,SHIPX,shipy);
|
||||
turning++;
|
||||
}
|
||||
@ -481,7 +460,7 @@ int flying(void) {
|
||||
grsim_put_sprite(splash_right,
|
||||
SHIPX+1,36);
|
||||
}
|
||||
grsim_put_sprite(shadow_right,SHIPX+3,31+space_z);
|
||||
grsim_put_sprite(shadow_right,SHIPX+3,31+space_z.i);
|
||||
grsim_put_sprite(ship_right,SHIPX,shipy);
|
||||
turning--;
|
||||
}
|
||||
@ -532,6 +511,7 @@ static double space_z=4.5; // height of the camera above the plane
|
||||
static int horizon=-2; // number of pixels line 0 is below the horizon
|
||||
static double scale_x=20, scale_y=20;
|
||||
|
||||
double factor;
|
||||
double BETA=-0.5;
|
||||
|
||||
|
||||
@ -587,6 +567,10 @@ void draw_background_mode7(void) {
|
||||
hlin_double(ram[DRAW_PAGE], 0, 40, 6);
|
||||
|
||||
|
||||
// Move camera back a bit
|
||||
factor=space_z*BETA;
|
||||
printf("space_z=%lf BETA=%lf factor=%lf\n",space_z,BETA,factor);
|
||||
|
||||
for (screen_y = 8; screen_y < LOWRES_H; screen_y++) {
|
||||
// first calculate the distance of the line we are drawing
|
||||
distance = (space_z * scale_y) / (screen_y + horizon);
|
||||
@ -600,10 +584,6 @@ void draw_background_mode7(void) {
|
||||
line_dx = -our_sin(angle) * horizontal_scale;
|
||||
line_dy = our_cos(angle) * horizontal_scale;
|
||||
|
||||
double factor;
|
||||
// Move camera back a bit
|
||||
factor=space_z*BETA;
|
||||
|
||||
// calculate the starting position
|
||||
space_x = cx + ((distance+factor) * our_cos(angle)) - LOWRES_W/2 * line_dx;
|
||||
space_y = cy + ((distance+factor) * our_sin(angle)) - LOWRES_W/2 * line_dy;
|
||||
|
||||
Loading…
Reference in New Issue
Block a user