1 //
2 // Copyright 2017 The ANGLE Project Authors. All rights reserved.
3 // Use of this source code is governed by a BSD-style license that can be
4 // found in the LICENSE file.
5 //
6 // Regardless of the shader type, the following AST transformations are applied:
7 // - Add declaration of View_ID_OVR.
8 // - Replace every occurrence of gl_ViewID_OVR with ViewID_OVR, mark ViewID_OVR as internal and
9 // declare it with the same qualifier.
10 //
11 // If the shader type is a vertex shader, the following AST transformations are applied:
12 // - Replace every occurrence of gl_InstanceID with InstanceID, mark InstanceID as internal and set
13 // its qualifier to EvqTemporary.
14 // - Add initializers of ViewID_OVR and InstanceID to the beginning of the body of main. The pass
15 // should be executed before any variables get collected so that usage of gl_InstanceID is recorded.
16 // - If the output is ESSL or GLSL and the selectViewInNvGLSLVertexShader option is
17 // enabled, the expression
18 //   gl_Layer = int(ViewID_OVR) + multiviewBaseViewLayerIndex;
19 // is added after ViewID and InstanceID are initialized. Also, multiviewBaseViewLayerIndex is added
20 // as a uniform.
21 //
22 
23 #ifndef COMPILER_TRANSLATOR_TREEOPS_DECLAREANDINITBUILTINSFORINSTANCEDMULTIVIEW_H_
24 #define COMPILER_TRANSLATOR_TREEOPS_DECLAREANDINITBUILTINSFORINSTANCEDMULTIVIEW_H_
25 
26 #include "GLSLANG/ShaderLang.h"
27 #include "angle_gl.h"
28 #include "common/angleutils.h"
29 
30 namespace sh
31 {
32 
33 class TCompiler;
34 class TIntermBlock;
35 class TSymbolTable;
36 
37 [[nodiscard]] bool DeclareAndInitBuiltinsForInstancedMultiview(
38     TCompiler *compiler,
39     TIntermBlock *root,
40     unsigned numberOfViews,
41     GLenum shaderType,
42     const ShCompileOptions &compileOptions,
43     ShShaderOutput shaderOutput,
44     TSymbolTable *symbolTable);
45 
46 }  // namespace sh
47 
48 #endif  // COMPILER_TRANSLATOR_TREEOPS_DECLAREANDINITBUILTINSFORINSTANCEDMULTIVIEW_H_
49