camera.cpp

Ray tracing on PS3, using the acceleration of PPU, No SPE acceleration is used. The code must be com

/* Copyright (c) 2007 Massachusetts Institute of Technology
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
/**
 * camera.cpp - Implementation for routines of the Camera class
 * @author Brian Sweatt
 * 
 * As most of these methods are small, inlining may seem to be a natural choice to raise performance.
 * However, these methods are called at most once per frame and thus, will not show any appreciable
 * increase in performance over a frame if inlined.
 */
extern "C" {
#include <cross_product3_v.h>
}

#include "camera.h"

#include <math.h>
#include <stdio.h>


Camera :: Camera(const vector float &c, const vector float &d, 
		 const vector float &u, float a)
{
  vector float direction = _normalize3(d);
  vector float center = c;
  vector float horizontal = _normalize3(_cross_product3(direction, u));
  float tanAngle2 = 2.0f * tanf(a / 2.0f);  
  vector unsigned char splat_word_0 = (vector unsigned char){0, 1, 2, 3, 
							     0, 1, 2, 3, 
							     0, 1, 2, 3, 
							     0, 1, 2, 3};
  vector unsigned char splat_word_1 = (vector unsigned char){4, 5, 6, 7, 
							     4, 5, 6, 7, 
							     4, 5, 6, 7, 
							     4, 5, 6, 7};
  vector unsigned char splat_word_2 = (vector unsigned char){8, 9,10,11, 
							     8, 9,10,11, 
							     8, 9,10,11, 
							     8, 9,10,11};
  Hx = spu_shuffle(horizontal, horizontal, splat_word_0);
  Hy = spu_shuffle(horizontal, horizontal, splat_word_1);
  Hz = spu_shuffle(horizontal, horizontal, splat_word_2);
  vector float up = _normalize3(_cross_product3(horizontal, direction));
  Cx = spu_shuffle(center, center, splat_word_0);
  Cy = spu_shuffle(center, center, splat_word_1);
  Cz = spu_shuffle(center, center, splat_word_2);
  Ux = spu_shuffle(up, up, splat_word_0);
  Uy = spu_shuffle(up, up, splat_word_1);
  Uz = spu_shuffle(up, up, splat_word_2);
  size = spu_splats(tanAngle2);
  vector float negHalfSize = spu_mul(size, spu_splats(-0.5f));
  vector float lowerLeft = spu_add(up, horizontal);
  vector float vCenter = spu_add(center, direction);
  lowerLeft = spu_madd(lowerLeft, negHalfSize, vCenter);
  xLL = spu_shuffle(lowerLeft, lowerLeft, splat_word_0);
  yLL = spu_shuffle(lowerLeft, lowerLeft, splat_word_1);
  zLL = spu_shuffle(lowerLeft, lowerLeft, splat_word_2);
  
  printf("Camera center: %f %f %f\n", spu_extract(Cx, 0), spu_extract(Cy, 0), spu_extract(Cz, 0));
}

void Camera::setCenter(const vector float &center) {
  vector unsigned char splat_word_0 = (vector unsigned char){0, 1, 2, 3, 
							     0, 1, 2, 3, 
							     0, 1, 2, 3, 
							     0, 1, 2, 3};
  vector unsigned char splat_word_1 = (vector unsigned char){4, 5, 6, 7, 
							     4, 5, 6, 7, 
							     4, 5, 6, 7, 
							     4, 5, 6, 7};
  vector unsigned char splat_word_2 = (vector unsigned char){8, 9,10,11, 
							     8, 9,10,11, 
							     8, 9,10,11, 
							     8, 9,10,11};
  vector float newcx = spu_shuffle(center, center, splat_word_0);
  vector float newcy = spu_shuffle(center, center, splat_word_1);
  vector float newcz  = spu_shuffle(center, center, splat_word_2);
  vector float deltax = spu_sub(newcx, Cx);
  vector float deltay = spu_sub(newcy, Cy);
  vector float deltaz = spu_sub(newcz, Cz);
  Cx = newcx; Cy = newcy; Cz = newcz;
  xLL = spu_add(xLL, deltax);
  yLL = spu_add(yLL, deltay);
  zLL = spu_add(zLL, deltaz);
  //printf("Camera center: %f %f %f\n", spu_extract(center, 0), spu_extract(center, 1), spu_extract(center, 2));
}

vector float Camera::getDirection() {
  vector float dx, dy, dz;

  _cross_product3_v(&dx, &dy, &dz, Ux, Uy, Uz, Hx, Hy, Hz);
  return (vector float) {spu_extract(dx, 0), spu_extract(dy, 0), spu_extract(dz, 0), 0};
}

void Camera::setDirection(const vector float &d, const vector float &u) {
  vector float direction = _normalize3(d);

  //vector unsigned int usame = spu_cmpeq(newU, (vector foat) {0.0f, 0.0f, 0.0f, 0.0f});
  // Use the currently stored values for the center (this will not change) and up (this may change)
  //vector float u = (vector float) {spu_extract(Ux, 0), spu_extract(Uy, 0), spu_extract(Uz, 0), 0};
  //u = spu_sel(newU, u, usame);
  vector float center = (vector float) {spu_extract(Cx, 0), spu_extract(Cy, 0), spu_extract(Cz, 0), 0};
  vector float horizontal = _normalize3(_cross_product3(direction, u));
  vector unsigned char splat_word_0 = (vector unsigned char){0, 1, 2, 3, 
							     0, 1, 2, 3, 
							     0, 1, 2, 3, 
							     0, 1, 2, 3};
  vector unsigned char splat_word_1 = (vector unsigned char){4, 5, 6, 7, 
							     4, 5, 6, 7, 
							     4, 5, 6, 7, 
							     4, 5, 6, 7};
  vector unsigned char splat_word_2 = (vector unsigned char){8, 9,10,11, 
							     8, 9,10,11, 
							     8, 9,10,11, 
							     8, 9,10,11};
  Hx = spu_shuffle(horizontal, horizontal, splat_word_0);
  Hy = spu_shuffle(horizontal, horizontal, splat_word_1);
  Hz = spu_shuffle(horizontal, horizontal, splat_word_2);
  vector float up = _normalize3(_cross_product3(horizontal, direction));
  Ux = spu_shuffle(up, up, splat_word_0);
  Uy = spu_shuffle(up, up, splat_word_1);
  Uz = spu_shuffle(up, up, splat_word_2);
  vector float negHalfSize = spu_mul(size, spu_splats(-0.5f));
  vector float lowerLeft = spu_add(up, horizontal);
  vector float vCenter = spu_add(center, direction);
  lowerLeft = spu_madd(lowerLeft, negHalfSize, vCenter);
  xLL = spu_shuffle(lowerLeft, lowerLeft, splat_word_0);
  yLL = spu_shuffle(lowerLeft, lowerLeft, splat_word_1);
  zLL = spu_shuffle(lowerLeft, lowerLeft, splat_word_2);
}