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authorGravatar Florin Malita <fmalita@chromium.org>2017-05-25 15:29:13 -0400
committerGravatar Skia Commit-Bot <skia-commit-bot@chromium.org>2017-05-25 20:05:08 +0000
commitfabe0b26d05624ce7374f6ca89bd66df6142534e (patch)
treef32b5873b31185d7e86e6c48fbdbd654efb8af7a /src/effects/gradients/SkClampRange.cpp
parent1c214313248a4b5a69af14539608c54fb67c2bf8 (diff)
Relocate shaders to own dir
Consolidate all shader impls under src/shaders/. Change-Id: I450e37541214704c1ad9e379d9d753b7cc62fac3 Reviewed-on: https://skia-review.googlesource.com/17927 Commit-Queue: Florin Malita <fmalita@chromium.org> Reviewed-by: Herb Derby <herb@google.com>
Diffstat (limited to 'src/effects/gradients/SkClampRange.cpp')
-rw-r--r--src/effects/gradients/SkClampRange.cpp178
1 files changed, 0 insertions, 178 deletions
diff --git a/src/effects/gradients/SkClampRange.cpp b/src/effects/gradients/SkClampRange.cpp
deleted file mode 100644
index efc93959d1..0000000000
--- a/src/effects/gradients/SkClampRange.cpp
+++ /dev/null
@@ -1,178 +0,0 @@
-/*
- * Copyright 2011 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "SkClampRange.h"
-#include "SkMathPriv.h"
-
-static int SkCLZ64(uint64_t value) {
- int count = 0;
- if (value >> 32) {
- value >>= 32;
- } else {
- count += 32;
- }
- return count + SkCLZ(SkToU32(value));
-}
-
-static bool sk_64_smul_check(int64_t count, int64_t dx, int64_t* result) {
- // Do it the slow way until we have some assembly.
- if (dx == std::numeric_limits<int64_t>::min()) {
- return false; // SkTAbs overflow
- }
-
- SkASSERT(count >= 0);
- uint64_t ucount = static_cast<uint64_t>(count);
- uint64_t udx = static_cast<uint64_t>(SkTAbs(dx));
- int zeros = SkCLZ64(ucount) + SkCLZ64(udx);
- // this is a conservative check: it may return false when in fact it would not have overflowed.
- // Hackers Delight uses 34 as its convervative check, but that is for 32x32 multiplies.
- // Since we are looking at 64x64 muls, we add 32 to the check.
- if (zeros < (32 + 34)) {
- return false;
- }
- *result = count * dx;
- return true;
-}
-
-static bool sk_64_sadd_check(int64_t a, int64_t b, int64_t* result) {
- if (a > 0) {
- if (b > std::numeric_limits<int64_t>::max() - a) {
- return false;
- }
- } else {
- if (b < std::numeric_limits<int64_t>::min() - a) {
- return false;
- }
- }
-
- *result = a + b;
- return true;
-}
-
-
-/*
- * returns [0..count] for the number of steps (<= count) for which x0 <= edge
- * given each step is followed by x0 += dx
- */
-static int chop(int64_t x0, SkGradFixed edge, int64_t x1, int64_t dx, int count) {
- SkASSERT(dx > 0);
- SkASSERT(count >= 0);
-
- if (x0 >= edge) {
- return 0;
- }
- if (x1 <= edge) {
- return count;
- }
- int64_t n = (edge - x0 + dx - 1) / dx;
- SkASSERT(n >= 0);
- SkASSERT(n <= count);
- return (int)n;
-}
-
-void SkClampRange::initFor1(SkGradFixed fx) {
- fCount0 = fCount1 = fCount2 = 0;
- if (fx <= 0) {
- fCount0 = 1;
- } else if (fx < kFracMax_SkGradFixed) {
- fCount1 = 1;
- fFx1 = fx;
- } else {
- fCount2 = 1;
- }
-}
-
-void SkClampRange::init(SkGradFixed fx0, SkGradFixed dx0, int count, int v0, int v1) {
- SkASSERT(count > 0);
-
- fV0 = v0;
- fV1 = v1;
-
- // special case 1 == count, as it is slightly common for skia
- // and avoids us ever calling divide or 64bit multiply
- if (1 == count) {
- this->initFor1(fx0);
- return;
- }
-
- int64_t fx = fx0;
- int64_t dx = dx0;
-
- // start with ex equal to the last computed value
- int64_t count_times_dx, ex;
- if (!sk_64_smul_check(count - 1, dx, &count_times_dx) ||
- !sk_64_sadd_check(fx, count_times_dx, &ex)) {
- // we can't represent the computed end in 32.32, so just draw something (first color)
- fCount1 = fCount2 = 0;
- fCount0 = count;
- return;
- }
-
- if ((uint64_t)(fx | ex) <= kFracMax_SkGradFixed) {
- fCount0 = fCount2 = 0;
- fCount1 = count;
- fFx1 = fx0;
- return;
- }
- if (fx <= 0 && ex <= 0) {
- fCount1 = fCount2 = 0;
- fCount0 = count;
- return;
- }
- if (fx >= kFracMax_SkGradFixed && ex >= kFracMax_SkGradFixed) {
- fCount0 = fCount1 = 0;
- fCount2 = count;
- return;
- }
-
- // now make ex be 1 past the last computed value
- ex += dx;
-
- bool doSwap = dx < 0;
-
- if (doSwap) {
- ex -= dx;
- fx -= dx;
- SkTSwap(fx, ex);
- dx = -dx;
- }
-
-
- fCount0 = chop(fx, 0, ex, dx, count);
- SkASSERT(fCount0 >= 0);
- SkASSERT(fCount0 <= count);
- count -= fCount0;
- fx += fCount0 * dx;
- SkASSERT(fx >= 0);
- SkASSERT(fCount0 == 0 || (fx - dx) < 0);
- fCount1 = chop(fx, kFracMax_SkGradFixed, ex, dx, count);
- SkASSERT(fCount1 >= 0);
- SkASSERT(fCount1 <= count);
- count -= fCount1;
- fCount2 = count;
-
-#ifdef SK_DEBUG
- fx += fCount1 * dx;
- SkASSERT(fx <= ex);
- if (fCount2 > 0) {
- SkASSERT(fx >= kFracMax_SkGradFixed);
- if (fCount1 > 0) {
- SkASSERT(fx - dx < kFracMax_SkGradFixed);
- }
- }
-#endif
-
- if (doSwap) {
- SkTSwap(fCount0, fCount2);
- SkTSwap(fV0, fV1);
- dx = -dx;
- }
-
- if (fCount1 > 0) {
- fFx1 = fx0 + fCount0 * dx;
- }
-}