Reland "Fix precision caps and rrect/ellipse effect precisions"

This is a reland of e42180022720f2fcfd3c634cad855506a7940591
Original change's description:
> Fix precision caps and rrect/ellipse effect precisions
>
> Replaces all the complex precision caps with a single flag that says
> whether "float" == fp32. Updates the ellipse and rrect effects to
> use float coords, and use the scale workaround when float != fp32.
>
> Bug: skia:7190
> Change-Id: Ieccff9f38acd05e5cec78fe90d01a5da901a9307
> Reviewed-on: https://skia-review.googlesource.com/70961
> Commit-Queue: Chris Dalton <csmartdalton@google.com>
> Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
> Reviewed-by: Brian Salomon <bsalomon@google.com>

TBR=bsalomon@google.com

Bug: skia:7190
Change-Id: I7ced37a64164b83d86f6a957c35e10ce9085aba0
Reviewed-on: https://skia-review.googlesource.com/72760
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/include/private/GrTypesPriv.h b/include/private/GrTypesPriv.h
index a90944064f..cd1c0d4483 100644
--- a/include/private/GrTypesPriv.h
+++ b/include/private/GrTypesPriv.h
@@ -909,6 +909,33 @@ static inline bool GrPixelConfigIsUnorm(GrPixelConfig config) {
     return false;
 }
 
+/**
+ * Precision qualifier that should be used with a sampler.
+ */
+static inline GrSLPrecision GrSLSamplerPrecision(GrPixelConfig config) {
+    switch (config) {
+        case kUnknown_GrPixelConfig:
+        case kAlpha_8_GrPixelConfig:
+        case kGray_8_GrPixelConfig:
+        case kRGB_565_GrPixelConfig:
+        case kRGBA_4444_GrPixelConfig:
+        case kRGBA_8888_GrPixelConfig:
+        case kBGRA_8888_GrPixelConfig:
+        case kSRGBA_8888_GrPixelConfig:
+        case kSBGRA_8888_GrPixelConfig:
+        case kRGBA_8888_sint_GrPixelConfig:
+            return kLow_GrSLPrecision;
+        case kRGBA_float_GrPixelConfig:
+        case kRG_float_GrPixelConfig:
+            return kHigh_GrSLPrecision;
+        case kAlpha_half_GrPixelConfig:
+        case kRGBA_half_GrPixelConfig:
+            return kMedium_GrSLPrecision;
+    }
+    SK_ABORT("Unexpected type");
+    return kHigh_GrSLPrecision;
+}
+
 static inline GrPixelConfigIsClamped GrGetPixelConfigIsClamped(GrPixelConfig config) {
     return GrPixelConfigIsFloatingPoint(config) ? GrPixelConfigIsClamped::kNo
                                                 : GrPixelConfigIsClamped::kYes;