Fix cancelled vertices on iOS OpenGL ES simulator

filament/src/details/Material.cpp

@@ -442,9 +442,15 @@ Program FMaterial::getProgramBuilderWithVariants(
         }
     }
 
+    int platformId = 0;
+#if defined(IOS)
+    platformId = 1;
+#endif
+
     program.specializationConstants({
             { 0, (int)mEngine.getSupportedFeatureLevel() },
-            { 1, (int)CONFIG_MAX_INSTANCES }
+            { 1, (int)CONFIG_MAX_INSTANCES },
+            { 2, platformId }
     });
 
     return program;

libs/filamat/src/shaders/CodeGenerator.cpp

@@ -123,6 +123,7 @@ utils::io::sstream& CodeGenerator::generateProlog(utils::io::sstream& out, Shade
     out << '\n';
     generateSpecificationConstant(out, "BACKEND_FEATURE_LEVEL", 0, 1);
     generateSpecificationConstant(out, "CONFIG_MAX_INSTANCES", 1, (int)CONFIG_MAX_INSTANCES);
+    generateSpecificationConstant(out, "TARGET_PLATFORM", 2, 0);
 
     out << '\n';
     out << SHADERS_COMMON_DEFINES_GLSL_DATA;

shaders/src/common_defines.glsl

@@ -22,3 +22,11 @@
 
 #define float3x3 mat3
 #define float4x4 mat4
+
+#define TARGET_PLATFORM_UNKNOWN     0
+#define TARGET_PLATFORM_IOS         1
+#if defined(TARGET_GLES_ENVIRONMENT)
+const bool openGlesIos = TARGET_PLATFORM == TARGET_PLATFORM_IOS;
+#else
+const bool openGlesIos = false;
+#endif

shaders/src/getters.fs

@@ -128,7 +128,7 @@ highp vec4 getCascadeLightSpacePosition(uint cascade) {
     // For the first cascade, return the interpolated light space position.
     // This branch will be coherent (mostly) for neighboring fragments, and it's worth avoiding
     // the matrix multiply inside computeLightSpacePosition.
-    if (cascade == 0u) {
+    if (cascade == 0u && !openGlesIos) {
         // Note: this branch may cause issues with derivatives
         return vertex_lightSpacePosition;
     }

shaders/src/main.vs

@@ -141,11 +141,16 @@ void main() {
 #endif
 
 #if defined(VARIANT_HAS_SHADOWING) && defined(VARIANT_HAS_DIRECTIONAL_LIGHTING)
-    vertex_lightSpacePosition = computeLightSpacePosition(
-            vertex_worldPosition.xyz, vertex_worldNormal,
-            frameUniforms.lightDirection,
-            shadowUniforms.shadows[0].normalBias,
-            shadowUniforms.shadows[0].lightFromWorldMatrix);
+    if (openGlesIos) {
+        // Hack for OpenGL ES on iOS.
+        vertex_lightSpacePosition = vec4(1.0);
+    } else {
+        vertex_lightSpacePosition = computeLightSpacePosition(
+                vertex_worldPosition.xyz, vertex_worldNormal,
+                frameUniforms.lightDirection,
+                shadowUniforms.shadows[0].normalBias,
+                shadowUniforms.shadows[0].lightFromWorldMatrix);
+    }
 #endif
 
 #endif // !defined(USE_OPTIMIZED_DEPTH_VERTEX_SHADER)