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

This reverts commit e42180022720f2fcfd3c634cad855506a7940591.

Reason for revert: Also may be responsible for layout test failures? Playing it safe.

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=egdaniel@google.com,bsalomon@google.com,csmartdalton@google.com,ethannicholas@google.com

Change-Id: Idca2f0390e7a0eb85010255183f2f27332b8d26d
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:7190
Reviewed-on: https://skia-review.googlesource.com/72540
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>

1 files changed, 14 insertions, 3 deletions

diff --git a/src/gpu/mtl/GrMtlCaps.mm b/src/gpu/mtl/GrMtlCaps.mm
index 2354b85e64..d431f0a1e1 100644
--- a/src/gpu/mtl/GrMtlCaps.mm
+++ b/src/gpu/mtl/GrMtlCaps.mm
@@ -229,10 +229,21 @@ void GrMtlCaps::initShaderCaps() {
     shaderCaps->fTexelFetchSupport = false;
     shaderCaps->fVertexIDSupport = false;
     shaderCaps->fImageLoadStoreSupport = false;
+    shaderCaps->fShaderPrecisionVaries = false; // ???
 
-    // Metal uses IEEE float and half floats so assuming those values here.
-    shaderCaps->fFloatIs32Bits = true;
-    shaderCaps->fHalfIs32Bits = false;
+    // Metal uses IEEE float and half floats so using those values here.
+    for (int s = 0; s < kGrShaderTypeCount; ++s) {
+        auto& highp = shaderCaps->fFloatPrecisions[s][kHigh_GrSLPrecision];
+        highp.fLogRangeLow = highp.fLogRangeHigh = 127;
+        highp.fBits = 23;
+
+        auto& mediump = shaderCaps->fFloatPrecisions[s][kMedium_GrSLPrecision];
+        mediump.fLogRangeLow = mediump.fLogRangeHigh = 15;
+        mediump.fBits = 10;
+
+        shaderCaps->fFloatPrecisions[s][kLow_GrSLPrecision] = mediump;
+    }
+    shaderCaps->initSamplerPrecisionTable();
 
     shaderCaps->fMaxVertexSamplers =
     shaderCaps->fMaxFragmentSamplers = 16;