Add SkRasterPipeline blitter.
This is now pixel-exact with the existing sRGB SW impl as far as I've tested.
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2146413002
CQ_INCLUDE_TRYBOTS=master.client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot,Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Debug-ASAN-Trybot
Committed: https://skia.googlesource.com/skia/+/3011e337693a9786f62d8de9ac4b239ad6dbdaca
Review-Url: https://codereview.chromium.org/2146413002
diff --git a/src/core/SkRasterPipelineBlitter.cpp b/src/core/SkRasterPipelineBlitter.cpp
new file mode 100644
index 0000000..46a822e
--- /dev/null
+++ b/src/core/SkRasterPipelineBlitter.cpp
@@ -0,0 +1,326 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkBlitter.h"
+#include "SkColor.h"
+#include "SkColorFilter.h"
+#include "SkPM4f.h"
+#include "SkPM4fPriv.h"
+#include "SkRasterPipeline.h"
+#include "SkShader.h"
+#include "SkSRGB.h"
+#include "SkXfermode.h"
+
+
+class SkRasterPipelineBlitter : public SkBlitter {
+public:
+ static SkBlitter* Create(const SkPixmap&, const SkPaint&, SkTBlitterAllocator*);
+
+ SkRasterPipelineBlitter(SkPixmap dst,
+ SkRasterPipeline shader,
+ SkRasterPipeline colorFilter,
+ SkRasterPipeline xfermode,
+ SkPM4f paintColor)
+ : fDst(dst)
+ , fShader(shader)
+ , fColorFilter(colorFilter)
+ , fXfermode(xfermode)
+ , fPaintColor(paintColor)
+ {}
+
+ void blitH (int x, int y, int w) override;
+ void blitAntiH(int x, int y, const SkAlpha[], const int16_t[]) override;
+ void blitMask (const SkMask&, const SkIRect& clip) override;
+
+ // TODO: The default implementations of the other blits look fine,
+ // but some of them like blitV could probably benefit from custom
+ // blits using something like a SkRasterPipeline::runFew() method.
+
+private:
+ SkPixmap fDst;
+ SkRasterPipeline fShader, fColorFilter, fXfermode;
+ SkPM4f fPaintColor;
+
+ typedef SkBlitter INHERITED;
+};
+
+SkBlitter* SkCreateRasterPipelineBlitter(const SkPixmap& dst,
+ const SkPaint& paint,
+ SkTBlitterAllocator* alloc) {
+ return SkRasterPipelineBlitter::Create(dst, paint, alloc);
+}
+
+
+// The default shader produces a constant color (from the SkPaint).
+static void SK_VECTORCALL constant_color(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ auto color = st->ctx<const SkPM4f*>();
+ r = color->r();
+ g = color->g();
+ b = color->b();
+ a = color->a();
+ st->next(x, r,g,b,a, dr,dg,db,da);
+}
+
+// The default transfer mode is srcover, s' = s + d*(1-sa).
+static void SK_VECTORCALL srcover(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ auto A = 1.0f - a;
+ r += dr*A;
+ g += dg*A;
+ b += db*A;
+ a += da*A;
+ st->next(x, r,g,b,a, dr,dg,db,da);
+}
+
+static Sk4f lerp(const Sk4f& from, const Sk4f& to, const Sk4f& cov) {
+ return from + (to-from)*cov;
+}
+
+// s' = d(1-c) + sc, for a constant c.
+static void SK_VECTORCALL lerp_constant_float(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ Sk4f c = *st->ctx<const float*>();
+
+ r = lerp(dr, r, c);
+ g = lerp(dg, g, c);
+ b = lerp(db, b, c);
+ a = lerp(da, a, c);
+ st->next(x, r,g,b,a, dr,dg,db,da);
+}
+
+// s' = d(1-c) + sc, 4 pixels at a time for 8-bit coverage.
+static void SK_VECTORCALL lerp_a8(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ auto ptr = st->ctx<const uint8_t*>() + x;
+ Sk4f c = SkNx_cast<float>(Sk4b::Load(ptr)) * (1/255.0f);
+
+ r = lerp(dr, r, c);
+ g = lerp(dg, g, c);
+ b = lerp(db, b, c);
+ a = lerp(da, a, c);
+ st->next(x, r,g,b,a, dr,dg,db,da);
+}
+
+// Tail variant of lerp_a8() handling 1 pixel at a time.
+static void SK_VECTORCALL lerp_a8_1(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ auto ptr = st->ctx<const uint8_t*>() + x;
+ Sk4f c = *ptr * (1/255.0f);
+
+ r = lerp(dr, r, c);
+ g = lerp(dg, g, c);
+ b = lerp(db, b, c);
+ a = lerp(da, a, c);
+ st->next(x, r,g,b,a, dr,dg,db,da);
+}
+
+static void upscale_lcd16(const Sk4h& lcd16, Sk4f* r, Sk4f* g, Sk4f* b) {
+ Sk4i _32_bit = SkNx_cast<int>(lcd16);
+
+ *r = SkNx_cast<float>(_32_bit & SK_R16_MASK_IN_PLACE) * (1.0f / SK_R16_MASK_IN_PLACE);
+ *g = SkNx_cast<float>(_32_bit & SK_G16_MASK_IN_PLACE) * (1.0f / SK_G16_MASK_IN_PLACE);
+ *b = SkNx_cast<float>(_32_bit & SK_B16_MASK_IN_PLACE) * (1.0f / SK_B16_MASK_IN_PLACE);
+}
+
+// s' = d(1-c) + sc, 4 pixels at a time for 565 coverage.
+static void SK_VECTORCALL lerp_lcd16(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ auto ptr = st->ctx<const uint16_t*>() + x;
+ Sk4f cr, cg, cb;
+ upscale_lcd16(Sk4h::Load(ptr), &cr, &cg, &cb);
+
+ r = lerp(dr, r, cr);
+ g = lerp(dg, g, cg);
+ b = lerp(db, b, cb);
+ a = 1.0f;
+ st->next(x, r,g,b,a, dr,dg,db,da);
+}
+
+// Tail variant of lerp_lcd16() handling 1 pixel at a time.
+static void SK_VECTORCALL lerp_lcd16_1(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ auto ptr = st->ctx<const uint16_t*>() + x;
+ Sk4f cr, cg, cb;
+ upscale_lcd16({*ptr,0,0,0}, &cr, &cg, &cb);
+
+ r = lerp(dr, r, cr);
+ g = lerp(dg, g, cg);
+ b = lerp(db, b, cb);
+ a = 1.0f;
+ st->next(x, r,g,b,a, dr,dg,db,da);
+}
+
+// Load 4 8-bit sRGB pixels from SkPMColor order to RGBA.
+static void SK_VECTORCALL load_d_srgb(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ auto ptr = st->ctx<const uint32_t*>() + x;
+
+ dr = { sk_linear_from_srgb[(ptr[0] >> SK_R32_SHIFT) & 0xff],
+ sk_linear_from_srgb[(ptr[1] >> SK_R32_SHIFT) & 0xff],
+ sk_linear_from_srgb[(ptr[2] >> SK_R32_SHIFT) & 0xff],
+ sk_linear_from_srgb[(ptr[3] >> SK_R32_SHIFT) & 0xff] };
+
+ dg = { sk_linear_from_srgb[(ptr[0] >> SK_G32_SHIFT) & 0xff],
+ sk_linear_from_srgb[(ptr[1] >> SK_G32_SHIFT) & 0xff],
+ sk_linear_from_srgb[(ptr[2] >> SK_G32_SHIFT) & 0xff],
+ sk_linear_from_srgb[(ptr[3] >> SK_G32_SHIFT) & 0xff] };
+
+ db = { sk_linear_from_srgb[(ptr[0] >> SK_B32_SHIFT) & 0xff],
+ sk_linear_from_srgb[(ptr[1] >> SK_B32_SHIFT) & 0xff],
+ sk_linear_from_srgb[(ptr[2] >> SK_B32_SHIFT) & 0xff],
+ sk_linear_from_srgb[(ptr[3] >> SK_B32_SHIFT) & 0xff] };
+
+ // TODO: this >> doesn't really need mask if we make it logical instead of arithmetic.
+ da = SkNx_cast<float>((Sk4i::Load(ptr) >> SK_A32_SHIFT) & 0xff) * (1/255.0f);
+
+ st->next(x, r,g,b,a, dr,dg,db,da);
+}
+
+// Tail variant of load_d_srgb() handling 1 pixel at a time.
+static void SK_VECTORCALL load_d_srgb_1(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ auto ptr = st->ctx<const uint32_t*>() + x;
+
+ dr = { sk_linear_from_srgb[(*ptr >> SK_R32_SHIFT) & 0xff], 0,0,0 };
+ dg = { sk_linear_from_srgb[(*ptr >> SK_G32_SHIFT) & 0xff], 0,0,0 };
+ db = { sk_linear_from_srgb[(*ptr >> SK_B32_SHIFT) & 0xff], 0,0,0 };
+ da = { (1/255.0f) * (*ptr >> SK_A32_SHIFT) , 0,0,0 };
+
+ st->next(x, r,g,b,a, dr,dg,db,da);
+}
+
+// Write out 4 pixels as 8-bit SkPMColor-order sRGB.
+static void SK_VECTORCALL store_srgb(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ auto dst = st->ctx<uint32_t*>() + x;
+ ( sk_linear_to_srgb(r) << SK_R32_SHIFT
+ | sk_linear_to_srgb(g) << SK_G32_SHIFT
+ | sk_linear_to_srgb(b) << SK_B32_SHIFT
+ | Sk4f_round(255.0f*a) << SK_A32_SHIFT).store(dst);
+}
+
+// Tail variant of store_srgb() handling 1 pixel at a time.
+static void SK_VECTORCALL store_srgb_1(SkRasterPipeline::Stage* st, size_t x,
+ Sk4f r, Sk4f g, Sk4f b, Sk4f a,
+ Sk4f dr, Sk4f dg, Sk4f db, Sk4f da) {
+ auto dst = st->ctx<uint32_t*>() + x;
+ *dst = Sk4f_toS32(swizzle_rb_if_bgra({ r[0], g[0], b[0], a[0] }));
+}
+
+
+template <typename Effect>
+static bool append_effect_stages(const Effect* effect, SkRasterPipeline* pipeline) {
+ return !effect || effect->appendStages(pipeline);
+}
+
+
+SkBlitter* SkRasterPipelineBlitter::Create(const SkPixmap& dst,
+ const SkPaint& paint,
+ SkTBlitterAllocator* alloc) {
+ if (!dst.info().gammaCloseToSRGB()) {
+ return nullptr; // TODO: f16, etc.
+ }
+ if (paint.getShader()) {
+ return nullptr; // TODO: need to work out how shaders and their contexts work
+ }
+
+ SkRasterPipeline shader, colorFilter, xfermode;
+ if (!append_effect_stages(paint.getColorFilter(), &colorFilter) ||
+ !append_effect_stages(paint.getXfermode(), &xfermode )) {
+ return nullptr;
+ }
+
+ auto blitter = alloc->createT<SkRasterPipelineBlitter>(
+ dst,
+ shader, colorFilter, xfermode,
+ SkColor4f::FromColor(paint.getColor()).premul());
+
+ if (!paint.getShader()) {
+ blitter->fShader.append(constant_color, &blitter->fPaintColor);
+ }
+ if (!paint.getXfermode()) {
+ blitter->fXfermode.append(srcover);
+ }
+
+ return blitter;
+}
+
+void SkRasterPipelineBlitter::blitH(int x, int y, int w) {
+ auto dst = fDst.writable_addr(0,y);
+
+ SkRasterPipeline p;
+ p.extend(fShader);
+ p.extend(fColorFilter);
+ p.append(load_d_srgb, load_d_srgb_1, dst);
+ p.extend(fXfermode);
+ p.append(store_srgb, store_srgb_1, dst);
+
+ p.run(x, w);
+}
+
+void SkRasterPipelineBlitter::blitAntiH(int x, int y, const SkAlpha aa[], const int16_t runs[]) {
+ auto dst = fDst.writable_addr(0,y);
+ float coverage;
+
+ SkRasterPipeline p;
+ p.extend(fShader);
+ p.extend(fColorFilter);
+ p.append(load_d_srgb, load_d_srgb_1, dst);
+ p.extend(fXfermode);
+ p.append(lerp_constant_float, &coverage);
+ p.append(store_srgb, store_srgb_1, dst);
+
+ for (int16_t run = *runs; run > 0; run = *runs) {
+ coverage = *aa * (1/255.0f);
+ p.run(x, run);
+
+ x += run;
+ runs += run;
+ aa += run;
+ }
+}
+
+void SkRasterPipelineBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {
+ if (mask.fFormat == SkMask::kBW_Format) {
+ // TODO: native BW masks?
+ return INHERITED::blitMask(mask, clip);
+ }
+
+ int x = clip.left();
+ for (int y = clip.top(); y < clip.bottom(); y++) {
+ auto dst = fDst.writable_addr(0,y);
+
+ SkRasterPipeline p;
+ p.extend(fShader);
+ p.extend(fColorFilter);
+ p.append(load_d_srgb, load_d_srgb_1, dst);
+ p.extend(fXfermode);
+ switch (mask.fFormat) {
+ case SkMask::kA8_Format:
+ p.append(lerp_a8, lerp_a8_1, mask.getAddr8(x,y)-x);
+ break;
+ case SkMask::kLCD16_Format:
+ p.append(lerp_lcd16, lerp_lcd16_1, mask.getAddrLCD16(x,y)-x);
+ break;
+ default: break;
+ }
+ p.append(store_srgb, store_srgb_1, dst);
+
+ p.run(x, clip.width());
+ }
+}