| Index: src/effects/gradients/SkSweepGradient.cpp
|
| diff --git a/src/effects/gradients/SkSweepGradient.cpp b/src/effects/gradients/SkSweepGradient.cpp
|
| index c38205b844ab15eeda5a1a1a022672f404fbe6ea..d60d8b6050d8971e624f14f943660a6502403026 100644
|
| --- a/src/effects/gradients/SkSweepGradient.cpp
|
| +++ b/src/effects/gradients/SkSweepGradient.cpp
|
| @@ -52,178 +52,7 @@ void SkSweepGradient::flatten(SkFlattenableWriteBuffer& buffer) const {
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| buffer.writePoint(fCenter);
|
| }
|
|
|
| -#ifndef SK_SCALAR_IS_FLOAT
|
| -#ifdef COMPUTE_SWEEP_TABLE
|
| -#define PI 3.14159265
|
| -static bool gSweepTableReady;
|
| -static uint8_t gSweepTable[65];
|
| -
|
| -/* Our table stores precomputed values for atan: [0...1] -> [0..PI/4]
|
| - We scale the results to [0..32]
|
| -*/
|
| -static const uint8_t* build_sweep_table() {
|
| - if (!gSweepTableReady) {
|
| - const int N = 65;
|
| - const double DENOM = N - 1;
|
| -
|
| - for (int i = 0; i < N; i++)
|
| - {
|
| - double arg = i / DENOM;
|
| - double v = atan(arg);
|
| - int iv = (int)round(v * DENOM * 2 / PI);
|
| -// printf("[%d] atan(%g) = %g %d\n", i, arg, v, iv);
|
| - printf("%d, ", iv);
|
| - gSweepTable[i] = iv;
|
| - }
|
| - gSweepTableReady = true;
|
| - }
|
| - return gSweepTable;
|
| -}
|
| -#else
|
| -static const uint8_t gSweepTable[] = {
|
| - 0, 1, 1, 2, 3, 3, 4, 4, 5, 6, 6, 7, 8, 8, 9, 9,
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| - 10, 11, 11, 12, 12, 13, 13, 14, 15, 15, 16, 16, 17, 17, 18, 18,
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| - 19, 19, 20, 20, 21, 21, 22, 22, 23, 23, 24, 24, 25, 25, 25, 26,
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| - 26, 27, 27, 27, 28, 28, 29, 29, 29, 30, 30, 30, 31, 31, 31, 32,
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| - 32
|
| -};
|
| -static const uint8_t* build_sweep_table() { return gSweepTable; }
|
| -#endif
|
| -#endif
|
| -
|
| -// divide numer/denom, with a bias of 6bits. Assumes numer <= denom
|
| -// and denom != 0. Since our table is 6bits big (+1), this is a nice fit.
|
| -// Same as (but faster than) SkFixedDiv(numer, denom) >> 10
|
| -
|
| -//unsigned div_64(int numer, int denom);
|
| -#ifndef SK_SCALAR_IS_FLOAT
|
| -static unsigned div_64(int numer, int denom) {
|
| - SkASSERT(numer <= denom);
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| - SkASSERT(numer > 0);
|
| - SkASSERT(denom > 0);
|
| -
|
| - int nbits = SkCLZ(numer);
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| - int dbits = SkCLZ(denom);
|
| - int bits = 6 - nbits + dbits;
|
| - SkASSERT(bits <= 6);
|
| -
|
| - if (bits < 0) { // detect underflow
|
| - return 0;
|
| - }
|
| -
|
| - denom <<= dbits - 1;
|
| - numer <<= nbits - 1;
|
| -
|
| - unsigned result = 0;
|
| -
|
| - // do the first one
|
| - if ((numer -= denom) >= 0) {
|
| - result = 1;
|
| - } else {
|
| - numer += denom;
|
| - }
|
| -
|
| - // Now fall into our switch statement if there are more bits to compute
|
| - if (bits > 0) {
|
| - // make room for the rest of the answer bits
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| - result <<= bits;
|
| - switch (bits) {
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| - case 6:
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| - if ((numer = (numer << 1) - denom) >= 0)
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| - result |= 32;
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| - else
|
| - numer += denom;
|
| - case 5:
|
| - if ((numer = (numer << 1) - denom) >= 0)
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| - result |= 16;
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| - else
|
| - numer += denom;
|
| - case 4:
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| - if ((numer = (numer << 1) - denom) >= 0)
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| - result |= 8;
|
| - else
|
| - numer += denom;
|
| - case 3:
|
| - if ((numer = (numer << 1) - denom) >= 0)
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| - result |= 4;
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| - else
|
| - numer += denom;
|
| - case 2:
|
| - if ((numer = (numer << 1) - denom) >= 0)
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| - result |= 2;
|
| - else
|
| - numer += denom;
|
| - case 1:
|
| - default: // not strictly need, but makes GCC make better ARM code
|
| - if ((numer = (numer << 1) - denom) >= 0)
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| - result |= 1;
|
| - else
|
| - numer += denom;
|
| - }
|
| - }
|
| - return result;
|
| -}
|
| -#endif
|
| -
|
| -// Given x,y in the first quadrant, return 0..63 for the angle [0..90]
|
| -#ifndef SK_SCALAR_IS_FLOAT
|
| -static unsigned atan_0_90(SkFixed y, SkFixed x) {
|
| -#ifdef SK_DEBUG
|
| - {
|
| - static bool gOnce;
|
| - if (!gOnce) {
|
| - gOnce = true;
|
| - SkASSERT(div_64(55, 55) == 64);
|
| - SkASSERT(div_64(128, 256) == 32);
|
| - SkASSERT(div_64(2326528, 4685824) == 31);
|
| - SkASSERT(div_64(753664, 5210112) == 9);
|
| - SkASSERT(div_64(229376, 4882432) == 3);
|
| - SkASSERT(div_64(2, 64) == 2);
|
| - SkASSERT(div_64(1, 64) == 1);
|
| - // test that we handle underflow correctly
|
| - SkASSERT(div_64(12345, 0x54321234) == 0);
|
| - }
|
| - }
|
| -#endif
|
| -
|
| - SkASSERT(y > 0 && x > 0);
|
| - const uint8_t* table = build_sweep_table();
|
| -
|
| - unsigned result;
|
| - bool swap = (x < y);
|
| - if (swap) {
|
| - // first part of the atan(v) = PI/2 - atan(1/v) identity
|
| - // since our div_64 and table want v <= 1, where v = y/x
|
| - SkTSwap<SkFixed>(x, y);
|
| - }
|
| -
|
| - result = div_64(y, x);
|
| -
|
| -#ifdef SK_DEBUG
|
| - {
|
| - unsigned result2 = SkDivBits(y, x, 6);
|
| - SkASSERT(result2 == result ||
|
| - (result == 1 && result2 == 0));
|
| - }
|
| -#endif
|
| -
|
| - SkASSERT(result < SK_ARRAY_COUNT(gSweepTable));
|
| - result = table[result];
|
| -
|
| - if (swap) {
|
| - // complete the atan(v) = PI/2 - atan(1/v) identity
|
| - result = 64 - result;
|
| - // pin to 63
|
| - result -= result >> 6;
|
| - }
|
| -
|
| - SkASSERT(result <= 63);
|
| - return result;
|
| -}
|
| -#endif
|
| -
|
| // returns angle in a circle [0..2PI) -> [0..255]
|
| -#ifdef SK_SCALAR_IS_FLOAT
|
| static unsigned SkATan2_255(float y, float x) {
|
| // static const float g255Over2PI = 255 / (2 * SK_ScalarPI);
|
| static const float g255Over2PI = 40.584510488433314f;
|
| @@ -239,62 +68,6 @@ static unsigned SkATan2_255(float y, float x) {
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| SkASSERT(ir >= 0 && ir <= 255);
|
| return ir;
|
| }
|
| -#else
|
| -static unsigned SkATan2_255(SkFixed y, SkFixed x) {
|
| - if (x == 0) {
|
| - if (y == 0) {
|
| - return 0;
|
| - }
|
| - return y < 0 ? 192 : 64;
|
| - }
|
| - if (y == 0) {
|
| - return x < 0 ? 128 : 0;
|
| - }
|
| -
|
| - /* Find the right quadrant for x,y
|
| - Since atan_0_90 only handles the first quadrant, we rotate x,y
|
| - appropriately before calling it, and then add the right amount
|
| - to account for the real quadrant.
|
| - quadrant 0 : add 0 | x > 0 && y > 0
|
| - quadrant 1 : add 64 (90 degrees) | x < 0 && y > 0
|
| - quadrant 2 : add 128 (180 degrees) | x < 0 && y < 0
|
| - quadrant 3 : add 192 (270 degrees) | x > 0 && y < 0
|
| -
|
| - map x<0 to (1 << 6)
|
| - map y<0 to (3 << 6)
|
| - add = map_x ^ map_y
|
| - */
|
| - int xsign = x >> 31;
|
| - int ysign = y >> 31;
|
| - int add = ((-xsign) ^ (ysign & 3)) << 6;
|
| -
|
| -#ifdef SK_DEBUG
|
| - if (0 == add)
|
| - SkASSERT(x > 0 && y > 0);
|
| - else if (64 == add)
|
| - SkASSERT(x < 0 && y > 0);
|
| - else if (128 == add)
|
| - SkASSERT(x < 0 && y < 0);
|
| - else if (192 == add)
|
| - SkASSERT(x > 0 && y < 0);
|
| - else
|
| - SkDEBUGFAIL("bad value for add");
|
| -#endif
|
| -
|
| - /* This ^ trick makes x, y positive, and the swap<> handles quadrants
|
| - where we need to rotate x,y by 90 or -90
|
| - */
|
| - x = (x ^ xsign) - xsign;
|
| - y = (y ^ ysign) - ysign;
|
| - if (add & 64) { // quads 1 or 3 need to swap x,y
|
| - SkTSwap<SkFixed>(x, y);
|
| - }
|
| -
|
| - unsigned result = add + atan_0_90(y, x);
|
| - SkASSERT(result < 256);
|
| - return result;
|
| -}
|
| -#endif
|
|
|
| void SkSweepGradient::shadeSpan(int x, int y, SkPMColor* SK_RESTRICT dstC,
|
| int count) {
|
|
|