diff options
Diffstat (limited to 'libs/graphics/sgl/SkScan_Hairline.cpp')
| -rw-r--r-- | libs/graphics/sgl/SkScan_Hairline.cpp | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/libs/graphics/sgl/SkScan_Hairline.cpp b/libs/graphics/sgl/SkScan_Hairline.cpp new file mode 100644 index 0000000000..2af9e12163 --- /dev/null +++ b/libs/graphics/sgl/SkScan_Hairline.cpp @@ -0,0 +1,254 @@ +#include "SkScan.h" +#include "SkBlitter.h" +#include "SkRegion.h" +#include "SkFDot6.h" + +static void horiline(int x, int stopx, SkFixed fy, SkFixed dy, SkBlitter* blitter) +{ + SkASSERT(x < stopx); + + do { + blitter->blitH(x, fy >> 16, 1); + fy += dy; + } while (++x < stopx); +} + +static void vertline(int y, int stopy, SkFixed fx, SkFixed dx, SkBlitter* blitter) +{ + SkASSERT(y < stopy); + + do { + blitter->blitH(fx >> 16, y, 1); + fx += dx; + } while (++y < stopy); +} + +void SkScan::HairLine(const SkPoint& pt0, const SkPoint& pt1, const SkRegion* clip, SkBlitter* blitter) +{ + SkBlitterClipper clipper; + + SkFDot6 x0 = SkScalarToFDot6(pt0.fX); + SkFDot6 y0 = SkScalarToFDot6(pt0.fY); + SkFDot6 x1 = SkScalarToFDot6(pt1.fX); + SkFDot6 y1 = SkScalarToFDot6(pt1.fY); + + if (clip) + { + SkRect r; + SkRect16 ir; + SkPoint pts[2]; + + pts[0] = pt0; + pts[1] = pt1; + r.set(pts, 2); + r.roundOut(&ir); + + if (clip->quickReject(ir)) + return; + if (clip->quickContains(ir)) + clip = nil; + else + { + blitter = clipper.apply(blitter, clip); + } + } + + SkFDot6 dx = x1 - x0; + SkFDot6 dy = y1 - y0; + + if (SkAbs32(dx) > SkAbs32(dy)) // mostly horizontal + { + if (x0 > x1) // we want to go left-to-right + { + SkTSwap<SkFDot6>(x0, x1); + SkTSwap<SkFDot6>(y0, y1); + } + int ix0 = SkFDot6Round(x0); + int ix1 = SkFDot6Round(x1); + if (ix0 == ix1) // too short to draw + return; + + SkFixed slope = SkFixedDiv(dy, dx); + SkFixed startY = SkFDot6ToFixed(y0 + SkFixedMul(slope, (32 - x0) & 63)); + + horiline(ix0, ix1, startY, slope, blitter); + } + else // mostly vertical + { + if (y0 > y1) // we want to go top-to-bottom + { + SkTSwap<SkFDot6>(x0, x1); + SkTSwap<SkFDot6>(y0, y1); + } + int iy0 = SkFDot6Round(y0); + int iy1 = SkFDot6Round(y1); + if (iy0 == iy1) // too short to draw + return; + + SkFixed slope = SkFixedDiv(dx, dy); + SkFixed startX = SkFDot6ToFixed(x0 + SkFixedMul(slope, (32 - y0) & 63)); + + vertline(iy0, iy1, startX, slope, blitter); + } +} + +void SkScan::HairRect(const SkRect& rect, const SkRegion* clip, SkBlitter* blitter) +{ + SkPoint p0, p1; + + p0.set(rect.fLeft, rect.fTop); + p1.set(rect.fRight, rect.fTop); + SkScan::HairLine(p0, p1, clip, blitter); + p0.set(rect.fRight, rect.fBottom); + SkScan::HairLine(p0, p1, clip, blitter); + p1.set(rect.fLeft, rect.fBottom); + SkScan::HairLine(p0, p1, clip, blitter); + p0.set(rect.fLeft, rect.fTop); + SkScan::HairLine(p0, p1, clip, blitter); +} + +///////////////////////////////////////////////////////////////////////////////////////////////// + +#include "SkPath.h" +#include "SkGeometry.h" + +static bool quad_too_curvy(const SkPoint pts[3]) +{ + return true; +} + +static void hairquad(const SkPoint pts[3], const SkRegion* clip, SkBlitter* blitter, int level, + void (*lineproc)(const SkPoint&, const SkPoint&, const SkRegion* clip, SkBlitter*)) +{ +#if 1 + if (level > 0 && quad_too_curvy(pts)) + { + SkPoint tmp[5]; + + SkChopQuadAtHalf(pts, tmp); + hairquad(tmp, clip, blitter, level - 1, lineproc); + hairquad(&tmp[2], clip, blitter, level - 1, lineproc); + } + else + lineproc(pts[0], pts[2], clip, blitter); +#else + lineproc(pts[0], pts[1], clip, blitter); + lineproc(pts[1], pts[2], clip, blitter); +#endif +} + +static bool cubic_too_curvy(const SkPoint pts[4]) +{ + return true; +} + +static void haircubic(const SkPoint pts[4], const SkRegion* clip, SkBlitter* blitter, int level, + void (*lineproc)(const SkPoint&, const SkPoint&, const SkRegion*, SkBlitter*)) +{ + if (level > 0 && cubic_too_curvy(pts)) + { + SkPoint tmp[7]; + + SkChopCubicAt(pts, tmp, SK_Scalar1/2); + haircubic(tmp, clip, blitter, level - 1, lineproc); + haircubic(&tmp[3], clip, blitter, level - 1, lineproc); + } + else + lineproc(pts[0], pts[3], clip, blitter); +} + +#define kMaxCubicSubdivideLevel 6 +#define kMaxQuadSubdivideLevel 5 + +static void hair_path(const SkPath& path, const SkRegion* clip, SkBlitter* blitter, + void (*lineproc)(const SkPoint&, const SkPoint&, const SkRegion*, SkBlitter*)) +{ + if (path.isEmpty()) + return; + + const SkRect16* clipR = nil; + + if (clip) + { + SkRect bounds; + SkRect16 ibounds; + + path.computeBounds(&bounds, SkPath::kFast_BoundsType); + bounds.roundOut(&ibounds); + ibounds.inset(-1, -1); + + if (clip->quickReject(ibounds)) + return; + + if (clip->quickContains(ibounds)) + clip = nil; + else + clipR = &clip->getBounds(); + } + + SkPath::Iter iter(path, false); + SkPoint pts[4]; + SkPath::Verb verb; + + while ((verb = iter.next(pts)) != SkPath::kDone_Verb) + { + switch (verb) { + case SkPath::kLine_Verb: + lineproc(pts[0], pts[1], clip, blitter); + break; + case SkPath::kQuad_Verb: + hairquad(pts, clip, blitter, kMaxQuadSubdivideLevel, lineproc); + break; + case SkPath::kCubic_Verb: + haircubic(pts, clip, blitter, kMaxCubicSubdivideLevel, lineproc); + break; + default: + break; + } + } +} + +void SkScan::HairPath(const SkPath& path, const SkRegion* clip, SkBlitter* blitter) +{ + hair_path(path, clip, blitter, SkScan::HairLine); +} + +void SkScan::AntiHairPath(const SkPath& path, const SkRegion* clip, SkBlitter* blitter) +{ + hair_path(path, clip, blitter, SkScan::AntiHairLine); +} + +//////////////////////////////////////////////////////////////////////////////// + +void SkScan::FrameRect(const SkRect& r, SkScalar diameter, const SkRegion* clip, SkBlitter* blitter) +{ + SkASSERT(diameter > 0); + + if (r.isEmpty()) + return; + + SkScalar radius = diameter / 2; + SkRect outer, tmp; + + outer.set( r.fLeft - radius, r.fTop - radius, + r.fRight + radius, r.fBottom + radius); + + if (r.width() <= diameter || r.height() <= diameter) + { + SkScan::FillRect(outer, clip, blitter); + return; + } + + tmp.set(outer.fLeft, outer.fTop, outer.fRight, outer.fTop + diameter); + SkScan::FillRect(tmp, clip, blitter); + tmp.fTop = outer.fBottom - diameter; + tmp.fBottom = outer.fBottom; + SkScan::FillRect(tmp, clip, blitter); + + tmp.set(outer.fLeft, outer.fTop + diameter, outer.fLeft + diameter, outer.fBottom - diameter); + SkScan::FillRect(tmp, clip, blitter); + tmp.fLeft = outer.fRight - diameter; + tmp.fRight = outer.fRight; + SkScan::FillRect(tmp, clip, blitter); +} + |