fhrt_isoval_adapt.c File Reference

Handles Isovalue-Firsthit-rendermode. More...

#include "rendermodes.h"
#include "macros_isoval.h"

Defines
#define	REFINE
#define	SPIVIS
#define	TEST_FHRT_ISOVAL_ADAPT
#define	skymap_lookup(ftmpv, sc_off, zoff)
#define	FOURER
Functions
void	fhrt_isoval_adapt (rendersurf *rtsurf, uint32_t *voxel, float *ipos, float *ifor, float *iup, float *istr)
	Generate rays to cover the screen.
Variables
int	pos_x
int	pos_y
int	pos_z
float	ftmpv [4]
float	ftmpv_CUBE [4]
float	add_x [3]
float	add_y [3]
int	ADAPT_STEP
unsigned char	diffborder
	unsigned char diffborder=10;
SDL_Surface *	sky
uint32_t *	sdata
int	dist_estimate
int	isect_pos

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Detailed Description

Handles Isovalue-Firsthit-rendermode.

Binary search is employed in the area of interest to increase accuracy without a big hit on performance.

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Function Documentation

void fhrt_isoval_adapt (  rendersurf *  rtsurf, uint32_t *  voxel, float *  ipos, float *  ifor, float *  iup, float *  istr )

Generate rays to cover the screen. A simple adaptive raycasting-scheme is followed here. If the colors of adjacent coarse-grid-scanpoint differ too much, then new rays are cast. This happens "recursively" until either small enough blocks are reached, or the pixels don't differ too much and can therefore be filled with the "unique" color of the 4 adjacents pixels. Parameters: rtsurf  Pointer to surface to draw to. voxel  Pointer to the 3D dataset. ipos  Pointer to the camera-position. ifor  Pointer to the camera-viewvector. iup  Pointer to the camera-upvector. istr  Pointer to the camera-strafevector.

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