Several fixes for fp 16 rendering:

With the GPU backend, allow F16 render targets to be created (along with
any other renderable format). We were previously just falling back to 8888.

In SampleApp, if the window configuration is F16, don't render directly
to the primary surface (which is actually sRGB 8888). Intead, make an
off-screen F16 surface, then blit it back to the framebuffer when we're done.

In DM, clamp values outside of [0,1]. These were wrapping, producing very
incorrect images. (Many filters can trigger out-of-range values due to
ringing).

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1890923003

Review URL: https://codereview.chromium.org/1890923003

1 files changed, 18 insertions, 1 deletions

diff --git a/samplecode/SampleApp.cpp b/samplecode/SampleApp.cpp
index d4cf1cccb9..b7ba6f9580 100644
--- a/samplecode/SampleApp.cpp
+++ b/samplecode/SampleApp.cpp
@@ -294,7 +294,14 @@ public:
 #if SK_SUPPORT_GPU
         if (IsGpuDeviceType(dType) && fCurContext) {
             SkSurfaceProps props(win->getSurfaceProps());
-            return SkSurface::MakeRenderTargetDirect(fCurRenderTarget, &props).release();
+            if (kRGBA_F16_SkColorType == win->info().colorType()) {
+                // Need to make an off-screen F16 surface - the current render target is
+                // (probably) the wrong format.
+                return SkSurface::MakeRenderTarget(fCurContext, SkBudgeted::kNo, win->info(),
+                                                   fMSAASampleCount, &props).release();
+            } else {
+                return SkSurface::MakeRenderTargetDirect(fCurRenderTarget, &props).release();
+            }
         }
 #endif
         return nullptr;
@@ -318,6 +325,16 @@ public:
                                              bm.getPixels(),
                                              bm.rowBytes(),
                                              GrContext::kFlushWrites_PixelOp);
+            } else if (kRGBA_F16_SkColorType == win->info().colorType()) {
+                SkBitmap bm;
+                bm.allocPixels(win->info());
+                canvas->readPixels(&bm, 0, 0);
+                fCurRenderTarget->writePixels(0, 0, bm.width(), bm.height(),
+                                              SkImageInfo2GrPixelConfig(bm.info(),
+                                                                        *fCurContext->caps()),
+                                              bm.getPixels(),
+                                              bm.rowBytes(),
+                                              GrContext::kFlushWrites_PixelOp);
             }
         }
 #endif