[Impeller] fix Adreno precision issue in gaussian downsample. (#57212)

Fixes observed sampling problems on the adreno series where slightly different mediump/lowp behavior, resulting in the downsample shader showing "chunky" rendeering.
flutter · Dec 16, 2024 · ad02729 · ad02729
1 parent d373a93
commit ad02729
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Showing 2 changed files with 32 additions and 34 deletions.
diff --git a/impeller/entity/shaders/downsample.glsl b/impeller/entity/shaders/downsample.glsl
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-precision mediump float;
+precision highp float;
 
 #include <impeller/constants.glsl>
 #include <impeller/types.glsl>

diff --git a/impeller/tools/malioc.json b/impeller/tools/malioc.json
@@ -5274,7 +5274,7 @@
       "uses_late_zs_update": false,
       "variants": {
         "Main": {
-          "fp16_arithmetic": 80,
+          "fp16_arithmetic": 0,
           "has_stack_spilling": false,
           "performance": {
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@@ -5303,24 +5303,22 @@
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@@ -5329,7 +5327,7 @@
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@@ -5369,7 +5367,7 @@
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@@ -5394,7 +5392,7 @@
       "uses_late_zs_update": false,
       "variants": {
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+          "fp16_arithmetic": 0,
           "has_stack_spilling": false,
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@@ -5423,9 +5421,9 @@
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@@ -5436,9 +5434,9 @@
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@@ -5447,7 +5445,7 @@
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@@ -5487,14 +5485,14 @@
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@@ -8316,7 +8314,7 @@
       "uses_late_zs_update": false,
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+          "fp16_arithmetic": 0,
           "has_stack_spilling": false,
           "performance": {
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@@ -8345,9 +8343,9 @@
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@@ -8358,9 +8356,9 @@
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@@ -8388,7 +8386,7 @@
       "uses_late_zs_update": false,
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+          "fp16_arithmetic": 0,
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@@ -8417,9 +8415,9 @@
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@@ -8430,9 +8428,9 @@
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