static SkSurface* compat_surface(SkCanvas* canvas, const SkISize& size,
bool skipGPU) {
SkImageInfo info = SkImageInfo::MakeN32Premul(size);
#if SK_SUPPORT_GPU
SkBaseDevice* dev = canvas->getDevice();
if (!skipGPU && dev->accessRenderTarget()) {
SkGpuDevice* gd = (SkGpuDevice*)dev;
GrContext* ctx = gd->context();
return SkSurface::NewRenderTarget(ctx, info, 0);
}
#endif
return SkSurface::NewRaster(info);
}
virtual void onDraw(SkCanvas* canvas) {
SkBaseDevice* device = canvas->getTopDevice();
GrRenderTarget* target = device->accessRenderTarget();
GrContext* ctx = GetGr();
if (ctx && target) {
SkPMColor gTextureData[(2 * S) * (2 * S)];
static const int stride = 2 * S;
static const SkPMColor gray = SkPackARGB32(0x40, 0x40, 0x40, 0x40);
static const SkPMColor white = SkPackARGB32(0xff, 0xff, 0xff, 0xff);
static const SkPMColor red = SkPackARGB32(0x80, 0x80, 0x00, 0x00);
static const SkPMColor blue = SkPackARGB32(0x80, 0x00, 0x00, 0x80);
static const SkPMColor green = SkPackARGB32(0x80, 0x00, 0x80, 0x00);
static const SkPMColor black = SkPackARGB32(0x00, 0x00, 0x00, 0x00);
for (int i = 0; i < 2; ++i) {
int offset = 0;
// fill upper-left
for (int y = 0; y < S; ++y) {
for (int x = 0; x < S; ++x) {
gTextureData[offset + y * stride + x] = gray;
}
}
// fill upper-right
offset = S;
for (int y = 0; y < S; ++y) {
for (int x = 0; x < S; ++x) {
gTextureData[offset + y * stride + x] = white;
}
}
// fill lower left
offset = S * stride;
for (int y = 0; y < S; ++y) {
for (int x = 0; x < S; ++x) {
gTextureData[offset + y * stride + x] = black;
}
}
// fill lower right
offset = S * stride + S;
for (int y = 0; y < S; ++y) {
for (int x = 0; x < S; ++x) {
gTextureData[offset + y * stride + x] = gray;
}
}
GrTextureDesc desc;
// use RT flag bit because in GL it makes the texture be bottom-up
desc.fFlags = i ? kRenderTarget_GrTextureFlagBit :
kNone_GrTextureFlags;
desc.fConfig = kSkia8888_GrPixelConfig;
desc.fWidth = 2 * S;
desc.fHeight = 2 * S;
GrTexture* texture =
ctx->createUncachedTexture(desc, gTextureData, 0);
if (!texture) {
return;
}
GrAutoUnref au(texture);
GrContext::AutoClip acs(ctx, SkRect::MakeWH(2*S, 2*S));
ctx->setRenderTarget(target);
GrPaint paint;
paint.setBlendFunc(kOne_GrBlendCoeff, kISA_GrBlendCoeff);
SkMatrix vm;
if (i) {
vm.setRotate(90 * SK_Scalar1,
S * SK_Scalar1,
S * SK_Scalar1);
} else {
vm.reset();
}
ctx->setMatrix(vm);
SkMatrix tm;
tm = vm;
tm.postIDiv(2*S, 2*S);
paint.addColorTextureEffect(texture, tm);
ctx->drawRect(paint, SkRect::MakeWH(2*S, 2*S));
// now update the lower right of the texture in first pass
// or upper right in second pass
offset = 0;
for (int y = 0; y < S; ++y) {
for (int x = 0; x < S; ++x) {
gTextureData[offset + y * stride + x] =
((x + y) % 2) ? (i ? green : red) : blue;
}
}
texture->writePixels(S, (i ? 0 : S), S, S,
texture->config(), gTextureData,
4 * stride);
ctx->drawRect(paint, SkRect::MakeWH(2*S, 2*S));
}
}
}
