Retro68/Samples/Raytracer/raytracer2.cc
2015-07-16 20:57:34 +02:00

320 lines
6.8 KiB
C++

/*
Copyright 2012 Wolfgang Thaller.
This file is part of Retro68.
Retro68 is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Retro68 is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Retro68. If not, see <http://www.gnu.org/licenses/>.
*/
#ifdef __APPLE__
#include <Carbon/Carbon.h>
#include <ApplicationServices/ApplicationServices.h>
#else
#include <Quickdraw.h>
#include <MacMemory.h>
#include <Sound.h>
#include <Events.h>
#include <Fonts.h>
#include <NumberFormatting.h>
#ifdef __GNUC__
QDGlobals qd;
#endif
#endif
#include "fixed.h"
#include <cmath>
#include <algorithm>
#include <cstdlib>
#include <cstring>
#include <vector>
#include <cstdio>
using std::sqrt;
using std::floor;
inline int floor_to_int(float f)
{
return static_cast<int>(std::floor(f));
}
template<class T>
class vec3
{
public:
T x,y,z;
vec3(T x, T y, T z) : x(x), y(y), z(z) {}
vec3() : x(0), y(0), z(0) {}
vec3<T> operator+(const vec3<T>& other) const { return vec3(x + other.x, y + other.y, z + other.z); }
vec3<T> operator-(const vec3<T>& other) const { return vec3(x - other.x, y - other.y, z - other.z); }
vec3<T> operator*(T a) const { return vec3(x*a, y*a, z*a); }
T length() const { return sqrt(x*x + y*y + z*z); }
T operator*(const vec3<T>& other) const { return x*other.x + y*other.y + z*other.z; }
#if 1
vec3<T> normalize() const {
T l = length();
//if(l == 0)
// return *this;
//else
return (*this) * (T(1) / length());
}
#else
vec3<T> normalize() const {
T l = length();
if(l == 0)
return *this;
else
return vec3<T>(x/l, y/l, z/l);
}
#endif
};
template<class T>
bool hitSphere(vec3<T> p0, vec3<T> dir, T& t)
{
const vec3<T> center(0.0f, 1.0f, -6.0f);
const T r = 2.0f;
vec3<T> p0c(p0 - center);
/*
(x-xc)^2 + (y-yc)^2 + (z-zc)^2 = r^2;
(x0c + dx * t)^2 + (y0c + dy * t)^2 + (z0c + dz * t)^2 = r^2;
x0c^2 + 2*x0c*dx*t + dx^2*t^2 + y0c^2 + 2*y0c*dy*t + dy^2*t^2 + z0c^2 + 2 * z0c*dz*t + dz^2*t^2 = r^2
(dx^2 + dy^2 + dz^2)*t^2 + (2*x0c*dx + 2*y0c&dy + 2*z0c*dz) * t + x0c^2+y0c^2+z0c^2-r^2
*/
T a = dir*dir;
T b = 2*(p0c*dir);
T c = p0c*p0c - r*r;
T D = b*b - 4 * a * c;
if(D >= 0)
{
t = (-b - sqrt(D)) / (2*a);
return t >= 0;
}
return false;
}
template<class T>
T ray(int n, vec3<T> p0, vec3<T> dir)
{
#if 1
static const vec3<T> light = vec3<T>(-2,4,3).normalize();
if(1){
const vec3<T> center(0.0f, 1.0f, -6.0f);
const T r = 2.0f;
vec3<T> p0c(p0 - center);
/*
(x-xc)^2 + (y-yc)^2 + (z-zc)^2 = r^2;
(x0c + dx * t)^2 + (y0c + dy * t)^2 + (z0c + dz * t)^2 = r^2;
x0c^2 + 2*x0c*dx*t + dx^2*t^2 + y0c^2 + 2*y0c*dy*t + dy^2*t^2 + z0c^2 + 2 * z0c*dz*t + dz^2*t^2 = r^2
(dx^2 + dy^2 + dz^2)*t^2 + (2*x0c*dx + 2*y0c&dy + 2*z0c*dz) * t + x0c^2+y0c^2+z0c^2-r^2
*/
T a = dir*dir;
T b = 2*(p0c*dir);
T c = p0c*p0c - r*r;
T D = b*b - 4 * a * c;
if(D >= 0)
{
T t = (-b - sqrt(D)) / (2*a);
if(t > 0)
{
vec3<T> p = p0 + dir * t;
vec3<T> dir2 = (p - center) * (T(1)/r);
T l = dir2*dir;
T reflected;
if(n)
reflected = ray(n-1, p, dir - dir2*(l*2));
else
reflected = 0.0f;
T lambert = dir2 * light;
return T(0.2f) + T(0.4f) * std::max(T(0),lambert) + T(0.4f) * reflected;
}
}
}
if(dir.y < 0)
{
T t = (T(-1.5f) - p0.y) / dir.y;
vec3<T> p = p0 + dir*t;
T color;
if( (floor_to_int(p.x)
+ floor_to_int(p.z)) % 2 )
color = 0.8f;
else
color = 0.1f;
T ts;
if(hitSphere(p, light, ts))
color *= T(0.2f);
return std::min(T(1), color + T(0.5f) * ray(n-1, p,vec3<T>(dir.x, -dir.y, dir.z)));
}
#endif
return std::max(T(0), dir.y * T(0.3f));
}
typedef fixed numtype;
template<class T>
struct rand1
{
static T get()
{
return T(std::rand()) / T(32767.0f * 65536.0f);
}
};
template<>
struct rand1<fixed>
{
static fixed get()
{
return fixed(std::rand() >> 15, fixed::raw());
}
};
int main()
{
WindowPtr win;
#if !TARGET_API_MAC_CARBON
InitGraf(&qd.thePort);
InitFonts();
InitWindows();
InitMenus();
Rect r = qd.screenBits.bounds;
#else
BitMap bm;
GetQDGlobalsScreenBits(&bm);
Rect r = bm.bounds;
#endif
SetRect(&r, r.left + 5, r.top + 45, r.right - 5, r.bottom -5);
win = NewWindow(NULL, &r, "\pRaytracer (C++ Version)", true, 0, (WindowPtr)-1, false, 0);
#if !TARGET_API_MAC_CARBON
SetPort(win);
r = win->portRect;
#else
SetPortWindowPort(win);
GetPortBounds(GetWindowPort(win), &r);
#endif
EraseRect(&r);
numtype accum = 0.0f;
short cx = r.right /2;
short cy = r.bottom / 2;
long startTime = TickCount();
std::vector<numtype> accumV(r.right);
BitMap line;
std::vector<unsigned char> bits(((r.right + 31) / 8) & ~0x3);
SetRect(&line.bounds, 0,0,r.right,1);
line.rowBytes = bits.size();
line.baseAddr = (char*)(&bits[0]);
numtype preRandoms[29*31];
for(int i = 0; i < 29*31; i++)
{
numtype thresh = rand1<numtype>::get();
thresh = numtype(0.5f) + numtype(0.4f) * (thresh - numtype(0.5f));
preRandoms[i] = thresh;
}
int randIdx = 0;
for(int y = 0; y < r.bottom; y++)
{
std::fill(bits.begin(),bits.end(), 0);
for(int x = 0; x < r.right; x++)
{
numtype pixel;
// cam = (0,0,0)
// ray = t * (x-r.right/2, - (y-r.bottom/2), -1)
// plane: y = -2
pixel = ray(1,vec3<numtype>(),vec3<numtype>(numtype(x-cx)/numtype(cx),-numtype(y-cy)/numtype(cx),-1).normalize());
numtype thresh = preRandoms[randIdx++];
if(randIdx == 29*31)
randIdx = 0;
accum += pixel;
accum += accumV[x];
if(accum >= thresh)
accum -= 1;
else
{
//MoveTo(x,y);
//Line(0,0);
bits[x / 8] |= (0x80 >> (x%8));
}
accumV[x] = accum = accum / numtype(2);
}
Rect r2;
SetRect(&r2,0,y,r.right,y+1);
CopyBits(&line, &win->portBits, &line.bounds, &r2, srcCopy, NULL);
if(Button())
return 0;
#if TARGET_API_MAC_CARBON
// QDFlushPortBuffer(GetWindowPort(win),NULL);
#endif
}
long endTime = TickCount();
char buf[256];
unsigned char* pstr = (unsigned char*)buf;
std::sprintf(buf+1, "pps = %d %ld %ld %ld %ld", (int)( (long)r.right * r.bottom * 60 / (endTime - startTime) ),
fixed::nMul, fixed::nIMul, fixed::nDiv, fixed::nSqrt);
buf[0] = std::strlen(buf+1);
SetRect(&r, 10, 10, 10 + StringWidth(pstr) + 10, 30);
PaintRect(&r);
PenMode(patXor);
FrameRect(&r);
MoveTo(15,25);
TextMode(srcBic);
DrawString(pstr);
#if TARGET_API_MAC_CARBON
QDFlushPortBuffer(GetWindowPort(win),NULL);
#endif
while(!Button())
;
FlushEvents(everyEvent, -1);
return 0;
}