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-rw-r--r--render/meshdraw.c402
1 files changed, 0 insertions, 402 deletions
diff --git a/render/meshdraw.c b/render/meshdraw.c
deleted file mode 100644
index f5b1a3fb..00000000
--- a/render/meshdraw.c
+++ /dev/null
@@ -1,402 +0,0 @@
-#include <fitz.h>
-
-/*
- * polygon clipping
- */
-
-enum { IN, OUT, ENTER, LEAVE };
-enum { MAXV = 3 + 4 };
-enum { MAXN = 2 + FZ_MAXCOLORS };
-
-static int clipx(float val, int ismax, float *v1, float *v2, int n)
-{
- float t;
- int i;
- int v1o = ismax ? v1[0] > val : v1[0] < val;
- int v2o = ismax ? v2[0] > val : v2[0] < val;
- if (v1o + v2o == 0)
- return IN;
- if (v1o + v2o == 2)
- return OUT;
- if (v2o)
- {
- t = (val - v1[0]) / (v2[0] - v1[0]);
- v2[0] = val;
- v2[1] = v1[1] + t * (v2[1] - v1[1]);
- for (i = 2; i < n; i++)
- v2[i] = v1[i] + t * (v2[i] - v1[i]);
- return LEAVE;
- }
- else
- {
- t = (val - v2[0]) / (v1[0] - v2[0]);
- v1[0] = val;
- v1[1] = v2[1] + t * (v1[1] - v2[1]);
- for (i = 2; i < n; i++)
- v1[i] = v2[i] + t * (v1[i] - v2[i]);
- return ENTER;
- }
-}
-
-static int clipy(float val, int ismax, float *v1, float *v2, int n)
-{
- float t;
- int i;
- int v1o = ismax ? v1[1] > val : v1[1] < val;
- int v2o = ismax ? v2[1] > val : v2[1] < val;
- if (v1o + v2o == 0)
- return IN;
- if (v1o + v2o == 2)
- return OUT;
- if (v2o)
- {
- t = (val - v1[1]) / (v2[1] - v1[1]);
- v2[0] = v1[0] + t * (v2[0] - v1[0]);
- v2[1] = val;
- for (i = 2; i < n; i++)
- v2[i] = v1[i] + t * (v2[i] - v1[i]);
- return LEAVE;
- }
- else
- {
- t = (val - v2[1]) / (v1[1] - v2[1]);
- v1[0] = v2[0] + t * (v1[0] - v2[0]);
- v1[1] = val;
- for (i = 2; i < n; i++)
- v1[i] = v2[i] + t * (v1[i] - v2[i]);
- return ENTER;
- }
-}
-
-static inline void copyvert(float *dst, float *src, int n)
-{
- while (n--)
- *dst++ = *src++;
-}
-
-static int clippoly(float src[MAXV][MAXN],
- float dst[MAXV][MAXN], int len, int n,
- float val, int isy, int ismax)
-{
- float cv1[MAXN];
- float cv2[MAXN];
- int v1, v2, cp;
- int r;
-
- v1 = len - 1;
- cp = 0;
-
- for (v2 = 0; v2 < len; v2++)
- {
- copyvert(cv1, src[v1], n);
- copyvert(cv2, src[v2], n);
-
- if (isy)
- r = clipy(val, ismax, cv1, cv2, n);
- else
- r = clipx(val, ismax, cv1, cv2, n);
-
- switch (r)
- {
- case IN:
- copyvert(dst[cp++], cv2, n);
- break;
- case OUT:
- break;
- case LEAVE:
- copyvert(dst[cp++], cv2, n);
- break;
- case ENTER:
- copyvert(dst[cp++], cv1, n);
- copyvert(dst[cp++], cv2, n);
- break;
- }
- v1 = v2;
- }
-
- return cp;
-}
-
-/*
- * gouraud shaded polygon scan conversion
- */
-
-static inline void
-drawscan(fz_pixmap *pix, int y, int x1, int x2, int *v1, int *v2, int n)
-{
- unsigned char *p = pix->samples + ((y - pix->y) * pix->w + (x1 - pix->x)) * pix->n;
- int v[FZ_MAXCOLORS];
- int dv[FZ_MAXCOLORS];
- int w = x2 - x1;
- int k;
-
- assert(w >= 0);
- assert(y >= pix->y);
- assert(y < pix->y + pix->h);
- assert(x1 >= pix->x);
- assert(x2 <= pix->x + pix->w);
-
- if (w == 0)
- return;
-
- for (k = 0; k < n; k++)
- {
- v[k] = v1[k];
- dv[k] = (v2[k] - v1[k]) / w;
- }
-
- while (w--)
- {
- *p++ = 255;
- for (k = 0; k < n; k++)
- {
- *p++ = v[k] >> 16;
- v[k] += dv[k];
- }
- }
-}
-
-static inline int
-findnext(int gel[MAXV][MAXN], int len, int a, int *s, int *e, int d)
-{
- int b;
-
- while (1)
- {
- b = a + d;
- if (b == len)
- b = 0;
- if (b == -1)
- b = len - 1;
-
- if (gel[b][1] == gel[a][1])
- {
- a = b;
- continue;
- }
-
- if (gel[b][1] > gel[a][1])
- {
- *s = a;
- *e = b;
- return 0;
- }
-
- return 1;
- }
-}
-
-static inline void
-loadedge(int gel[MAXV][MAXN], int s, int e, int *ael, int *del, int n)
-{
- int swp, k, dy;
-
- if (gel[s][1] > gel[s][1])
- {
- swp = s; s = e; e = swp;
- }
-
- dy = gel[e][1] - gel[s][1];
-
- ael[0] = gel[s][0];
- del[0] = (gel[e][0] - gel[s][0]) / dy;
- for (k = 2; k < n; k++)
- {
- ael[k] = gel[s][k];
- del[k] = (gel[e][k] - gel[s][k]) / dy;
- }
-}
-
-static inline void
-stepedge(int *ael, int *del, int n)
-{
- int k;
- ael[0] += del[0];
- for (k = 2; k < n; k++)
- ael[k] += del[k];
-}
-
-void
-fz_drawtriangle(fz_pixmap *pix, float *av, float *bv, float *cv, int n)
-{
- float poly[MAXV][MAXN];
- float temp[MAXV][MAXN];
- float cx0 = pix->x;
- float cy0 = pix->y;
- float cx1 = pix->x + pix->w;
- float cy1 = pix->y + pix->h;
-
- int gel[MAXV][MAXN];
- int ael[2][MAXN];
- int del[2][MAXN];
- int y, s0, s1, e0, e1;
- int top, bot, len;
-
- int i, k;
-
- copyvert(poly[0], av, n);
- copyvert(poly[1], bv, n);
- copyvert(poly[2], cv, n);
-
- len = clippoly(poly, temp, 3, n, cx0, 0, 0);
- len = clippoly(temp, poly, len, n, cx1, 0, 1);
- len = clippoly(poly, temp, len, n, cy0, 1, 0);
- len = clippoly(temp, poly, len, n, cy1, 1, 1);
-
- if (len < 3)
- return;
-
- for (i = 0; i < len; i++)
- {
- gel[i][0] = fz_floor(poly[i][0] + 0.5) * 65536; /* trunc and fix */
- gel[i][1] = fz_floor(poly[i][1] + 0.5); /* y is not fixpoint */
- for (k = 2; k < n; k++)
- gel[i][k] = poly[i][k] * 65536; /* fix with precision */
- }
-
- top = bot = 0;
- for (i = 0; i < len; i++)
- {
- if (gel[i][1] < gel[top][1])
- top = i;
- if (gel[i][1] > gel[bot][1])
- bot = i;
- }
-
- if (gel[bot][1] - gel[top][1] == 0)
- return;
-
- y = gel[top][1];
-
- if (findnext(gel, len, top, &s0, &e0, 1))
- return;
- if (findnext(gel, len, top, &s1, &e1, -1))
- return;
-
- loadedge(gel, s0, e0, ael[0], del[0], n);
- loadedge(gel, s1, e1, ael[1], del[1], n);
-
- while (1)
- {
- int x0 = ael[0][0] >> 16;
- int x1 = ael[1][0] >> 16;
-
- if (ael[0][0] < ael[1][0])
- drawscan(pix, y, x0, x1, ael[0]+2, ael[1]+2, n-2);
- else
- drawscan(pix, y, x1, x0, ael[1]+2, ael[0]+2, n-2);
-
- stepedge(ael[0], del[0], n);
- stepedge(ael[1], del[1], n);
- y ++;
-
- if (y >= gel[e0][1])
- {
- if (findnext(gel, len, e0, &s0, &e0, 1))
- return;
- loadedge(gel, s0, e0, ael[0], del[0], n);
- }
-
- if (y >= gel[e1][1])
- {
- if (findnext(gel, len, e1, &s1, &e1, -1))
- return;
- loadedge(gel, s1, e1, ael[1], del[1], n);
- }
- }
-}
-
-/*
- * mesh drawing
- */
-
-fz_error *
-fz_rendershade(fz_shade *shade, fz_matrix ctm, fz_colorspace *destcs, fz_pixmap *dest)
-{
- unsigned char clut[256][3];
- unsigned char *s, *d;
- fz_error *error;
- fz_pixmap *temp;
- float rgb[3];
- float tri[3][MAXN];
- fz_point p;
- int i, j, k, n;
-
- assert(dest->n == 4);
-
- ctm = fz_concat(shade->matrix, ctm);
-
- if (shade->usefunction)
- {
- n = 3;
- error = fz_newpixmap(&temp, dest->x, dest->y, dest->w, dest->h, 2);
- if (error)
- return error;
- }
- else if (shade->cs != destcs)
- {
- n = 2 + shade->cs->n;
- error = fz_newpixmap(&temp, dest->x, dest->y, dest->w, dest->h,
- shade->cs->n + 1);
- if (error)
- return error;
- }
- else
- {
- n = 2 + shade->cs->n;
- temp = dest;
- }
-
- fz_clearpixmap(temp);
-
- for (i = 0; i < shade->meshlen; i++)
- {
- for (k = 0; k < 3; k++)
- {
- p.x = shade->mesh[(i * 3 + k) * n + 0];
- p.y = shade->mesh[(i * 3 + k) * n + 1];
- p = fz_transformpoint(ctm, p);
- tri[k][0] = p.x;
- tri[k][1] = p.y;
- for (j = 2; j < n; j++)
- tri[k][j] = shade->mesh[( i * 3 + k) * n + j] * 255;
- }
- fz_drawtriangle(temp, tri[0], tri[1], tri[2], n);
- }
-
- if (shade->usefunction)
- {
- for (i = 0; i < 256; i++)
- {
- fz_convertcolor(shade->cs, shade->function[i], destcs, rgb);
- clut[i][0] = rgb[0] * 255;
- clut[i][1] = rgb[1] * 255;
- clut[i][2] = rgb[2] * 255;
- }
-
- n = temp->w * temp->h;
- s = temp->samples;
- d = dest->samples;
-
- while (n--)
- {
- d[0] = s[0];
- d[1] = fz_mul255(s[0], clut[s[1]][0]);
- d[2] = fz_mul255(s[0], clut[s[1]][1]);
- d[3] = fz_mul255(s[0], clut[s[1]][2]);
- s += 2;
- d += 4;
- }
-
- fz_droppixmap(temp);
- }
-
- else if (shade->cs != destcs)
- {
- fz_convertpixmap(shade->cs, temp, destcs, dest);
- fz_droppixmap(temp);
- }
-
- return nil;
-}
-
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