bool SkMagnifierImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& src,
const Context&, SkBitmap* dst,
SkIPoint* offset) const {
if ((src.colorType() != kN32_SkColorType) ||
(fSrcRect.width() >= src.width()) ||
(fSrcRect.height() >= src.height())) {
return false;
}
SkAutoLockPixels alp(src);
SkASSERT(src.getPixels());
if (!src.getPixels() || src.width() <= 0 || src.height() <= 0) {
return false;
}
SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(src.width(), src.height()));
if (!device) {
return false;
}
*dst = device->accessBitmap(false);
SkAutoLockPixels alp_dst(*dst);
SkScalar inv_inset = fInset > 0 ? SkScalarInvert(fInset) : SK_Scalar1;
SkScalar inv_x_zoom = fSrcRect.width() / src.width();
SkScalar inv_y_zoom = fSrcRect.height() / src.height();
SkColor* sptr = src.getAddr32(0, 0);
SkColor* dptr = dst->getAddr32(0, 0);
int width = src.width(), height = src.height();
for (int y = 0; y < height; ++y) {
for (int x = 0; x < width; ++x) {
SkScalar x_dist = SkMin32(x, width - x - 1) * inv_inset;
SkScalar y_dist = SkMin32(y, height - y - 1) * inv_inset;
SkScalar weight = 0;
static const SkScalar kScalar2 = SkScalar(2);
// To create a smooth curve at the corners, we need to work on
// a square twice the size of the inset.
if (x_dist < kScalar2 && y_dist < kScalar2) {
x_dist = kScalar2 - x_dist;
y_dist = kScalar2 - y_dist;
SkScalar dist = SkScalarSqrt(SkScalarSquare(x_dist) +
SkScalarSquare(y_dist));
dist = SkMaxScalar(kScalar2 - dist, 0);
weight = SkMinScalar(SkScalarSquare(dist), SK_Scalar1);
} else {
SkScalar sqDist = SkMinScalar(SkScalarSquare(x_dist),
SkScalarSquare(y_dist));
weight = SkMinScalar(sqDist, SK_Scalar1);
}
SkScalar x_interp = SkScalarMul(weight, (fSrcRect.x() + x * inv_x_zoom)) +
(SK_Scalar1 - weight) * x;
SkScalar y_interp = SkScalarMul(weight, (fSrcRect.y() + y * inv_y_zoom)) +
(SK_Scalar1 - weight) * y;
int x_val = SkTPin(SkScalarFloorToInt(x_interp), 0, width - 1);
int y_val = SkTPin(SkScalarFloorToInt(y_interp), 0, height - 1);
*dptr = sptr[y_val * width + x_val];
dptr++;
}
}
return true;
}
bool SkPatchUtils::getVertexData(SkPatchUtils::VertexData* data, const SkPoint cubics[12],
const SkColor colors[4], const SkPoint texCoords[4], int lodX, int lodY) {
if (lodX < 1 || lodY < 1 || NULL == cubics || NULL == data) {
return false;
}
// check for overflow in multiplication
const int64_t lodX64 = (lodX + 1),
lodY64 = (lodY + 1),
mult64 = lodX64 * lodY64;
if (mult64 > SK_MaxS32) {
return false;
}
data->fVertexCount = SkToS32(mult64);
// it is recommended to generate draw calls of no more than 65536 indices, so we never generate
// more than 60000 indices. To accomplish that we resize the LOD and vertex count
if (data->fVertexCount > 10000 || lodX > 200 || lodY > 200) {
SkScalar weightX = static_cast<SkScalar>(lodX) / (lodX + lodY);
SkScalar weightY = static_cast<SkScalar>(lodY) / (lodX + lodY);
// 200 comes from the 100 * 2 which is the max value of vertices because of the limit of
// 60000 indices ( sqrt(60000 / 6) that comes from data->fIndexCount = lodX * lodY * 6)
lodX = static_cast<int>(weightX * 200);
lodY = static_cast<int>(weightY * 200);
data->fVertexCount = (lodX + 1) * (lodY + 1);
}
data->fIndexCount = lodX * lodY * 6;
data->fPoints = SkNEW_ARRAY(SkPoint, data->fVertexCount);
data->fIndices = SkNEW_ARRAY(uint16_t, data->fIndexCount);
// if colors is not null then create array for colors
SkPMColor colorsPM[kNumCorners];
if (NULL != colors) {
// premultiply colors to avoid color bleeding.
for (int i = 0; i < kNumCorners; i++) {
colorsPM[i] = SkPreMultiplyColor(colors[i]);
}
data->fColors = SkNEW_ARRAY(uint32_t, data->fVertexCount);
}
// if texture coordinates are not null then create array for them
if (NULL != texCoords) {
data->fTexCoords = SkNEW_ARRAY(SkPoint, data->fVertexCount);
}
SkPoint pts[kNumPtsCubic];
SkPatchUtils::getBottomCubic(cubics, pts);
FwDCubicEvaluator fBottom(pts);
SkPatchUtils::getTopCubic(cubics, pts);
FwDCubicEvaluator fTop(pts);
SkPatchUtils::getLeftCubic(cubics, pts);
FwDCubicEvaluator fLeft(pts);
SkPatchUtils::getRightCubic(cubics, pts);
FwDCubicEvaluator fRight(pts);
fBottom.restart(lodX);
fTop.restart(lodX);
SkScalar u = 0.0f;
int stride = lodY + 1;
for (int x = 0; x <= lodX; x++) {
SkPoint bottom = fBottom.next(), top = fTop.next();
fLeft.restart(lodY);
fRight.restart(lodY);
SkScalar v = 0.f;
for (int y = 0; y <= lodY; y++) {
int dataIndex = x * (lodY + 1) + y;
SkPoint left = fLeft.next(), right = fRight.next();
SkPoint s0 = SkPoint::Make((1.0f - v) * top.x() + v * bottom.x(),
(1.0f - v) * top.y() + v * bottom.y());
SkPoint s1 = SkPoint::Make((1.0f - u) * left.x() + u * right.x(),
(1.0f - u) * left.y() + u * right.y());
SkPoint s2 = SkPoint::Make(
(1.0f - v) * ((1.0f - u) * fTop.getCtrlPoints()[0].x()
+ u * fTop.getCtrlPoints()[3].x())
+ v * ((1.0f - u) * fBottom.getCtrlPoints()[0].x()
+ u * fBottom.getCtrlPoints()[3].x()),
(1.0f - v) * ((1.0f - u) * fTop.getCtrlPoints()[0].y()
+ u * fTop.getCtrlPoints()[3].y())
+ v * ((1.0f - u) * fBottom.getCtrlPoints()[0].y()
+ u * fBottom.getCtrlPoints()[3].y()));
data->fPoints[dataIndex] = s0 + s1 - s2;
if (NULL != colors) {
uint8_t a = uint8_t(bilerp(u, v,
SkScalar(SkColorGetA(colorsPM[kTopLeft_Corner])),
SkScalar(SkColorGetA(colorsPM[kTopRight_Corner])),
SkScalar(SkColorGetA(colorsPM[kBottomLeft_Corner])),
SkScalar(SkColorGetA(colorsPM[kBottomRight_Corner]))));
uint8_t r = uint8_t(bilerp(u, v,
SkScalar(SkColorGetR(colorsPM[kTopLeft_Corner])),
SkScalar(SkColorGetR(colorsPM[kTopRight_Corner])),
SkScalar(SkColorGetR(colorsPM[kBottomLeft_Corner])),
SkScalar(SkColorGetR(colorsPM[kBottomRight_Corner]))));
uint8_t g = uint8_t(bilerp(u, v,
SkScalar(SkColorGetG(colorsPM[kTopLeft_Corner])),
SkScalar(SkColorGetG(colorsPM[kTopRight_Corner])),
SkScalar(SkColorGetG(colorsPM[kBottomLeft_Corner])),
SkScalar(SkColorGetG(colorsPM[kBottomRight_Corner]))));
uint8_t b = uint8_t(bilerp(u, v,
SkScalar(SkColorGetB(colorsPM[kTopLeft_Corner])),
SkScalar(SkColorGetB(colorsPM[kTopRight_Corner])),
SkScalar(SkColorGetB(colorsPM[kBottomLeft_Corner])),
SkScalar(SkColorGetB(colorsPM[kBottomRight_Corner]))));
data->fColors[dataIndex] = SkPackARGB32(a,r,g,b);
}
if (NULL != texCoords) {
data->fTexCoords[dataIndex] = SkPoint::Make(
bilerp(u, v, texCoords[kTopLeft_Corner].x(),
texCoords[kTopRight_Corner].x(),
texCoords[kBottomLeft_Corner].x(),
texCoords[kBottomRight_Corner].x()),
bilerp(u, v, texCoords[kTopLeft_Corner].y(),
texCoords[kTopRight_Corner].y(),
texCoords[kBottomLeft_Corner].y(),
texCoords[kBottomRight_Corner].y()));
}
if(x < lodX && y < lodY) {
int i = 6 * (x * lodY + y);
data->fIndices[i] = x * stride + y;
data->fIndices[i + 1] = x * stride + 1 + y;
data->fIndices[i + 2] = (x + 1) * stride + 1 + y;
data->fIndices[i + 3] = data->fIndices[i];
data->fIndices[i + 4] = data->fIndices[i + 2];
data->fIndices[i + 5] = (x + 1) * stride + y;
}
v = SkScalarClampMax(v + 1.f / lodY, 1);
}
u = SkScalarClampMax(u + 1.f / lodX, 1);
}
return true;
}
