// d_init.c: rasterization driver initialization #include "quakedef.h"#include "r_shared.h"#include "d_local.h" #define NUM_MIPS 4 cvar_t d_subdiv16 = {"d_subdiv16", "1"};cvar_t d_mipcap = {"d_mipcap", "0"};cvar_t d_mipscale = {"d_mipscale", "1"}; surfcache_t *d_initial_rover;bool d_roverwrapped;int d_minmip;float d_scalemip[NUM_MIPS-1]; static float basemip[NUM_MIPS-1] = {1.0, 0.5*0.8, 0.25*0.8}; extern int d_aflatcolor; void (*d_drawspans) (espan_t *pspan); /*===============D_Init===============*/void D_Init (void){ 	r_skydirect = 1; 	Cvar_RegisterVariable (&d_subdiv16);	Cvar_RegisterVariable (&d_mipcap);	Cvar_RegisterVariable (&d_mipscale); 	r_drawpolys = false;	r_worldpolysbacktofront = false;	r_recursiveaffinetriangles = true;	r_pixbytes = 1;	r_aliasuvscale = 1.0;} /*===============D_SetupFrame===============*/void D_SetupFrame (void){	int i; 	if (r_dowarp)		d_viewbuffer = r_warpbuffer;	else		d_viewbuffer = (void *)(uint8_t *)vid.buffer; 	if (r_dowarp)		screenwidth = WARP_WIDTH;	else		screenwidth = vid.rowbytes; 	d_roverwrapped = false;	d_initial_rover = sc_rover; 	d_minmip = d_mipcap.value;	if (d_minmip > 3)		d_minmip = 3;	else if (d_minmip < 0)		d_minmip = 0; 	for (i=0 ; i<(NUM_MIPS-1) ; i++)		d_scalemip[i] = basemip[i] * d_mipscale.value; 	d_drawspans = D_DrawSpans8;	d_aflatcolor = 0;}