diff options
Diffstat (limited to 'src/gdisp/gdisp.c')
| -rw-r--r-- | src/gdisp/gdisp.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/src/gdisp/gdisp.c b/src/gdisp/gdisp.c index e03971a4..e3056ee6 100644 --- a/src/gdisp/gdisp.c +++ b/src/gdisp/gdisp.c @@ -1912,6 +1912,103 @@ void gdispGBlitArea(GDisplay *g, coord_t x, coord_t y, coord_t cx, coord_t cy, c #endif #if GDISP_NEED_ARC + #if (!GMISC_NEED_FIXEDTRIG && !GMISC_NEED_FASTTRIG) || !GFX_USE_GMISC + #include <math.h> + #endif + + void gdispGDrawThickArc(GDisplay *g, coord_t xc, coord_t yc, coord_t radiusStart, coord_t radiusEnd, coord_t start, coord_t end, color_t color) { + coord_t x, y, d, r; + coord_t startTan, endTan, curangle; + coord_t precision = 512; + + // Normalize the angles + if (start < 0) + start -= (start/360-1)*360; + else if (start >= 360) + start %= 360; + if (end < 0) + end -= (end/360-1)*360; + else if (end >= 360) + end %= 360; + + #if GFX_USE_GMISC && GMISC_NEED_FIXEDTRIG + startTan = ffsin(start % 45) * precision / ffcos(start % 45) + start / 45 * precision; + endTan = ffsin(end % 45) * precision / ffcos(end % 45) + end / 45 * precision; + #elif GFX_USE_GMISC && GMISC_NEED_FASTTRIG + startTan = fsin(start % 45) * precision / fcos(start % 45) + start / 45 * precision; + endTan = fsin(end % 45) * precision / fcos(end % 45) + end / 45 * precision; + #else + startTan = (tan((start % 45)*GFX_PI/180) + start / 45)* precision; + endTan = (tan((end % 45) *GFX_PI/180) + end / 45) * precision; + #endif + + MUTEX_ENTER(g); + g->p.color = color; + + //Draw concentric circles using Andres algorithm + for(r = radiusStart; r <= radiusEnd; r++) + { + x = 0; + y = r; + d = r - 1; + + while (y >= x){ + + //approximate tan + curangle = x*precision/y; + + if(end > start){ + //Draw points by symmetry + if(curangle > startTan && curangle < endTan){g->p.y = xc - x; g->p.x = yc + y; drawpixel_clip(g);} + if(curangle + 2*precision > startTan && curangle + 2*precision < endTan){g->p.y = xc - y; g->p.x = yc - x; drawpixel_clip(g);} + if(curangle + 4*precision > startTan && curangle + 4*precision < endTan){g->p.y = xc + x; g->p.x = yc - y; drawpixel_clip(g);} + if(curangle + 6*precision > startTan && curangle + 6*precision < endTan){g->p.y = xc + y; g->p.x = yc + x; drawpixel_clip(g);} + + curangle = precision - curangle; + + if(curangle + precision > startTan && curangle + precision < endTan){g->p.y = xc - y; g->p.x = yc + x; drawpixel_clip(g);} + if(curangle + 3*precision > startTan && curangle + 3*precision < endTan){g->p.y = xc - x; g->p.x = yc - y; drawpixel_clip(g);} + if(curangle + 5*precision > startTan && curangle + 5*precision < endTan){g->p.y = xc + y; g->p.x = yc - x; drawpixel_clip(g);} + if(curangle + 7*precision > startTan && curangle + 7*precision < endTan){g->p.y = xc + x; g->p.x = yc + y; drawpixel_clip(g);} + } + else{ + //Draw points by symmetry + if(curangle > startTan || curangle < endTan){g->p.y = xc - x; g->p.x = yc + y; drawpixel_clip(g);} + if(curangle + 2*precision > startTan || curangle + 2*precision < endTan){g->p.y = xc - y; g->p.x = yc - x; drawpixel_clip(g);} + if(curangle + 4*precision > startTan || curangle + 4*precision < endTan){g->p.y = xc + x; g->p.x = yc - y; drawpixel_clip(g);} + if(curangle + 6*precision > startTan || curangle + 6*precision < endTan){g->p.y = xc + y; g->p.x = yc + x; drawpixel_clip(g);} + + curangle = precision - curangle; + + if(curangle + precision > startTan || curangle + precision < endTan){g->p.y = xc - y; g->p.x = yc + x; drawpixel_clip(g);} + if(curangle + 3*precision > startTan || curangle + 3*precision < endTan){g->p.y = xc - x; g->p.x = yc - y; drawpixel_clip(g);} + if(curangle + 5*precision > startTan || curangle + 5*precision < endTan){g->p.y = xc + y; g->p.x = yc - x; drawpixel_clip(g);} + if(curangle + 7*precision > startTan || curangle + 7*precision < endTan){g->p.y = xc + x; g->p.x = yc + y; drawpixel_clip(g);} + } + + //Compute next point + if (d >= 2 * x){ + d -= 2 * x + 1; + x++; + } + else if (d < 2 * (r - y)){ + d += 2 * y - 1; + y--; + } + else{ + d += 2 * (y - x - 1); + y--; + x++; + } + } + } + + autoflush(g); + MUTEX_EXIT(g); + } +#endif + +#if GDISP_NEED_ARC void gdispGFillArc(GDisplay *g, coord_t x, coord_t y, coord_t radius, coord_t start, coord_t end, color_t color) { coord_t a, b, P; coord_t sy, ey; |