part.c File Reference

#include "sw.h"

Go to the source code of this file.

Classes
struct	partparms_t

Functions
static void	R_DrawParticle (void)
void	R_DrawParticles (void)

Variables
static partparms_t	partparms

Function Documentation

R_DrawParticle()

static void R_DrawParticle ( void  )

static

Definition at line 43 of file part.c.

{
    vec3_t  local, transformed;
    float   zi;
    byte    *pdest;
    short   *pz;
    int     i, izi, pix, count, u, v;
 
    /*
    ** transform the particle
    */
    VectorSubtract(partparms.particle->origin, r_origin, local);
 
    transformed[0] = DotProduct(local, partparms.right);
    transformed[1] = DotProduct(local, partparms.up);
    transformed[2] = DotProduct(local, partparms.pn);
 
    if (transformed[2] < PARTICLE_Z_CLIP)
        return;
 
    /*
    ** project the point
    */
    // FIXME: preadjust xcenter and ycenter
    zi = 1.0 / transformed[2];
    u = (int)(r_refdef.xcenter + zi * transformed[0] + 0.5);
    v = (int)(r_refdef.ycenter - zi * transformed[1] + 0.5);
 
    if (v > r_refdef.vrectbottom_particle ||
        u > r_refdef.vrectright_particle ||
        v < r_refdef.vrect.y ||
        u < r_refdef.vrect.x) {
        return;
    }
 
    /*
    ** compute addresses of zbuffer, framebuffer, and
    ** compute the Z-buffer reference value.
    */
    pz = d_zspantable[v] + u;
    pdest = d_spantable[v] + u * VID_BYTES;
    izi = (int)(zi * 0x8000);
 
    /*
    ** determine the screen area covered by the particle,
    ** which also means clamping to a min and max
    */
    pix = izi >> r_refdef.pix_shift;
    if (pix < r_refdef.pix_min)
        pix = r_refdef.pix_min;
    else if (pix > r_refdef.pix_max)
        pix = r_refdef.pix_max;
 
    /*
    ** render the appropriate pixels
    */
    for (count = pix; count; count--, pz += d_zwidth, pdest += d_screenrowbytes) {
        for (i = 0; i < pix; i++) {
            if (pz[i] <= izi) {
                pz[i] = izi;
                pdest[i * VID_BYTES + 0] = (pdest[i * VID_BYTES + 0] * partparms.one_minus_alpha + partparms.color[2]) >> 8;
                pdest[i * VID_BYTES + 1] = (pdest[i * VID_BYTES + 1] * partparms.one_minus_alpha + partparms.color[1]) >> 8;
                pdest[i * VID_BYTES + 2] = (pdest[i * VID_BYTES + 2] * partparms.one_minus_alpha + partparms.color[0]) >> 8;
            }
        }
    }
}

Referenced by R_DrawParticles().

R_DrawParticles()

void R_DrawParticles

(

void

)

Definition at line 119 of file part.c.

{
    particle_t *p;
    int         i;
    int         alpha;
 
    VectorScale(vright, r_refdef.xscaleshrink, partparms.right);
    VectorScale(vup, r_refdef.yscaleshrink, partparms.up);
    VectorCopy(vpn, partparms.pn);
 
    for (p = r_newrefdef.particles, i = 0; i < r_newrefdef.num_particles; i++, p++) {
        partparms.particle = p;
 
        alpha = 255 * p->alpha;
        partparms.one_minus_alpha = 255 - alpha;
 
        if (p->color == -1) {
            partparms.color[0] = p->rgba.u8[0] * alpha;
            partparms.color[1] = p->rgba.u8[1] * alpha;
            partparms.color[2] = p->rgba.u8[2] * alpha;
        } else {
            color_t color;
 
            color.u32 = d_8to24table[p->color & 0xff];
            partparms.color[0] = color.u8[0] * alpha;
            partparms.color[1] = color.u8[1] * alpha;
            partparms.color[2] = color.u8[2] * alpha;
        }
 
        R_DrawParticle();
    }
}

Referenced by R_RenderFrame().

Variable Documentation

partparms

partparms_t partparms

static

Definition at line 28 of file part.c.

Referenced by R_DrawParticle(), and R_DrawParticles().