ref: a9a57c39e57aa437c032558d093929b48b24f47a
dir: /src/zline.c/
#include "../include/zbuffer.h" #include <stdlib.h> #define ZCMP(z, zpix) (!(zbdt) || z >= (zpix)) /* TODO: Implement point size. */ /* TODO: Implement blending for lines and points. */ void ZB_plot(ZBuffer* zb, ZBufferPoint* p) { GLint zz, y, x; GLubyte zbdw = zb->depth_write; GLubyte zbdt = zb->depth_test; GLfloat zbps = zb->pointsize; TGL_BLEND_VARS zz = p->z >> ZB_POINT_Z_FRAC_BITS; if (zbps == 1) { GLushort* pz; PIXEL* pp; pz = zb->zbuf + (p->y * zb->xsize + p->x); pp = (PIXEL*)((GLbyte*)zb->pbuf + zb->linesize * p->y + p->x * PSZB); if (ZCMP(zz, *pz)) { #if TGL_FEATURE_BLEND == 1 if (!zb->enable_blend) *pp = RGB_TO_PIXEL(p->r, p->g, p->b); else TGL_BLEND_FUNC_RGB(p->r, p->g, p->b, (*pp)) #else *pp = RGB_TO_PIXEL(p->r, p->g, p->b); #endif if (zbdw) *pz = zz; } } else { PIXEL col = RGB_TO_PIXEL(p->r, p->g, p->b); GLfloat hzbps = zbps / 2.0f; GLint bx = (GLfloat)p->x - hzbps; GLint ex = (GLfloat)p->x + hzbps; GLint by = (GLfloat)p->y - hzbps; GLint ey = (GLfloat)p->y + hzbps; bx = (bx < 0) ? 0 : bx; by = (by < 0) ? 0 : by; ex = (ex > zb->xsize) ? zb->xsize : ex; ey = (ey > zb->ysize) ? zb->ysize : ey; for (y = by; y < ey; y++) for (x = bx; x < ex; x++) { GLushort* pz = zb->zbuf + (y * zb->xsize + x); PIXEL* pp = (PIXEL*)((GLbyte*)zb->pbuf + zb->linesize * y + x * PSZB); if (ZCMP(zz, *pz)) { #if TGL_FEATURE_BLEND == 1 if (!zb->enable_blend) *pp = col; else TGL_BLEND_FUNC_RGB(p->r, p->g, p->b, (*pp)) #else *pp = col; #endif if (zbdw) *pz = zz; } } } } #define INTERP_Z static void ZB_line_flat_z(ZBuffer* zb, ZBufferPoint* p1, ZBufferPoint* p2, GLint color) { GLubyte zbdt = zb->depth_test; GLubyte zbdw = zb->depth_write; #include "zline.h" } /* line with color GLinterpolation */ #define INTERP_Z #define INTERP_RGB static void ZB_line_interp_z(ZBuffer* zb, ZBufferPoint* p1, ZBufferPoint* p2) { GLubyte zbdt = zb->depth_test; GLubyte zbdw = zb->depth_write; #include "zline.h" } /* no Z GLinterpolation */ static void ZB_line_flat(ZBuffer* zb, ZBufferPoint* p1, ZBufferPoint* p2, GLint color) { #include "zline.h" } #define INTERP_RGB static void ZB_line_interp(ZBuffer* zb, ZBufferPoint* p1, ZBufferPoint* p2) { #include "zline.h" } void ZB_line_z(ZBuffer* zb, ZBufferPoint* p1, ZBufferPoint* p2) { GLint color1, color2; color1 = RGB_TO_PIXEL(p1->r, p1->g, p1->b); color2 = RGB_TO_PIXEL(p2->r, p2->g, p2->b); /* choose if the line should have its color GLinterpolated or not */ if (color1 == color2) { ZB_line_flat_z(zb, p1, p2, color1); } else { ZB_line_interp_z(zb, p1, p2); } } void ZB_line(ZBuffer* zb, ZBufferPoint* p1, ZBufferPoint* p2) { GLint color1, color2; color1 = RGB_TO_PIXEL(p1->r, p1->g, p1->b); color2 = RGB_TO_PIXEL(p2->r, p2->g, p2->b); /* choose if the line should have its color GLinterpolated or not */ if (color1 == color2) { ZB_line_flat(zb, p1, p2, color1); } else { ZB_line_interp(zb, p1, p2); } }