blob: 67221050a48daa1d9c309a8568cdfb80655ed626 [file] [log] [blame]
// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "skia/ext/bitmap_platform_device_mac.h"
#include "skia/ext/skia_utils_mac.h"
#include "SkMatrix.h"
#include "SkPath.h"
#include "SkTypes.h"
#include "SkUtils.h"
namespace skia {
// TODO(brettw) remove this when the gfx namespaces are all removed.
using namespace gfx;
namespace {
// Constrains position and size to fit within available_size.
bool constrain(int available_size, int* position, int *size) {
if (*position < 0) {
*size += *position;
*position = 0;
}
if (*size > 0 && *position < available_size) {
int overflow = (*position + *size) - available_size;
if (overflow > 0) {
*size -= overflow;
}
return true;
}
return false;
}
// Sets the opacity of the specified value to 0xFF.
void makeOpaqueAlphaAdjuster(uint32_t* pixel) {
*pixel |= 0xFF000000;
}
} // namespace
PlatformDeviceMac::PlatformDeviceMac(const SkBitmap& bitmap)
: SkDevice(bitmap) {
}
void PlatformDeviceMac::makeOpaque(int x, int y, int width, int height) {
processPixels(x, y, width, height, makeOpaqueAlphaAdjuster);
}
// Set up the CGContextRef for peaceful coexistence with Skia
void PlatformDeviceMac::InitializeCGContext(CGContextRef context) {
// CG defaults to the same settings as Skia
}
// static
void PlatformDeviceMac::LoadPathToCGContext(CGContextRef context,
const SkPath& path) {
// instead of a persistent attribute of the context, CG specifies the fill
// type per call, so we just have to load up the geometry.
CGContextBeginPath(context);
SkPoint points[4] = { {0, 0}, {0, 0}, {0, 0}, {0, 0} };
SkPath::Iter iter(path, false);
for (SkPath::Verb verb = iter.next(points); verb != SkPath::kDone_Verb;
verb = iter.next(points)) {
switch (verb) {
case SkPath::kMove_Verb: { // iter.next returns 1 point
CGContextMoveToPoint(context, points[0].fX, points[0].fY);
break;
}
case SkPath::kLine_Verb: { // iter.next returns 2 points
CGContextAddLineToPoint(context, points[1].fX, points[1].fY);
break;
}
case SkPath::kQuad_Verb: { // iter.next returns 3 points
CGContextAddQuadCurveToPoint(context, points[1].fX, points[1].fY,
points[2].fX, points[2].fY);
break;
}
case SkPath::kCubic_Verb: { // iter.next returns 4 points
CGContextAddCurveToPoint(context, points[1].fX, points[1].fY,
points[2].fX, points[2].fY,
points[3].fX, points[3].fY);
break;
}
case SkPath::kClose_Verb: { // iter.next returns 1 point (the last point)
break;
}
case SkPath::kDone_Verb: // iter.next returns 0 points
default: {
SkASSERT(false);
break;
}
}
}
CGContextClosePath(context);
}
// static
void PlatformDeviceMac::LoadTransformToCGContext(CGContextRef context,
const SkMatrix& matrix) {
// CoreGraphics can concatenate transforms, but not reset the current one.
// So in order to get the required behavior here, we need to first make
// the current transformation matrix identity and only then load the new one.
// Reset matrix to identity.
CGAffineTransform orig_cg_matrix = CGContextGetCTM(context);
CGAffineTransform orig_cg_matrix_inv = CGAffineTransformInvert(orig_cg_matrix);
CGContextConcatCTM(context, orig_cg_matrix_inv);
// assert that we have indeed returned to the identity Matrix.
SkASSERT(CGAffineTransformIsIdentity(CGContextGetCTM(context)));
// Convert xform to CG-land.
// Our coordinate system is flipped to match WebKit's so we need to modify
// the xform to match that.
SkMatrix transformed_matrix = matrix;
SkScalar sy = matrix.getScaleY() * (SkScalar)-1;
transformed_matrix.setScaleY(sy);
size_t height = CGBitmapContextGetHeight(context);
SkScalar ty = -matrix.getTranslateY(); // y axis is flipped.
transformed_matrix.setTranslateY(ty + (SkScalar)height);
CGAffineTransform cg_matrix = SkMatrixToCGAffineTransform(transformed_matrix);
// Load final transform into context.
CGContextConcatCTM(context, cg_matrix);
}
// static
void PlatformDeviceMac::LoadClippingRegionToCGContext(
CGContextRef context,
const SkRegion& region,
const SkMatrix& transformation) {
if (region.isEmpty()) {
// region can be empty, in which case everything will be clipped.
SkRect rect;
rect.setEmpty();
CGContextClipToRect(context, SkRectToCGRect(rect));
} else if (region.isRect()) {
// Do the transformation.
SkRect rect;
rect.set(region.getBounds());
transformation.mapRect(&rect);
SkIRect irect;
rect.round(&irect);
CGContextClipToRect(context, SkIRectToCGRect(irect));
} else {
// It is complex.
SkPath path;
region.getBoundaryPath(&path);
// Clip. Note that windows clipping regions are not affected by the
// transform so apply it manually.
path.transform(transformation);
// TODO(playmobil): Implement.
SkASSERT(false);
// LoadPathToDC(context, path);
// hrgn = PathToRegion(context);
}
}
} // namespace skia