From a52858d8e2d071fe880ed68ade478551e5eed7a9 Mon Sep 17 00:00:00 2001
From: assiduous <assiduous@diligentgraphics.com>
Date: Tue, 7 Nov 2023 12:42:29 -0800
Subject: [PATCH] PBR renderer: fixed point mode in GLES

It requires setting the value of gl_PointSize in the vertex shader
---
 PBR/src/PBR_Renderer.cpp          | 9 +++++++--
 Shaders/PBR/private/RenderPBR.vsh | 5 +++++
 shaders_inc/RenderPBR.vsh.h       | 5 +++++
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/PBR/src/PBR_Renderer.cpp b/PBR/src/PBR_Renderer.cpp
index 2cd01209..512fa833 100644
--- a/PBR/src/PBR_Renderer.cpp
+++ b/PBR/src/PBR_Renderer.cpp
@@ -866,8 +866,13 @@ void PBR_Renderer::CreatePSO(PsoHashMapType& PsoHashMap, const GraphicsPipelineD
     ShaderCI.SourceLanguage             = SHADER_SOURCE_LANGUAGE_HLSL;
     ShaderCI.pShaderSourceStreamFactory = pCompoundSourceFactory;
 
-    const auto Macros = DefineMacros(PSOFlags);
-    ShaderCI.Macros   = Macros;
+    auto Macros = DefineMacros(PSOFlags);
+    if (GraphicsDesc.PrimitiveTopology == PRIMITIVE_TOPOLOGY_POINT_LIST && m_Device.GetDeviceInfo().IsGLDevice())
+    {
+        // If gl_PointSize is not defined, points are not rendered in GLES
+        Macros.Add("USE_GL_POINT_SIZE", "1");
+    }
+    ShaderCI.Macros = Macros;
 
     RefCntAutoPtr<IShader> pVS;
     {
diff --git a/Shaders/PBR/private/RenderPBR.vsh b/Shaders/PBR/private/RenderPBR.vsh
index f08abdeb..e2ec2f03 100644
--- a/Shaders/PBR/private/RenderPBR.vsh
+++ b/Shaders/PBR/private/RenderPBR.vsh
@@ -93,4 +93,9 @@ void main(in  VSInput  VSIn,
 #if USE_TEXCOORD1
     VSOut.UV1      = VSIn.UV1;
 #endif
+
+#ifdef USE_GL_POINT_SIZE
+    // If gl_PointSize is not defined, points are not rendered in GLES
+    gl_PointSize = 1.0;
+#endif
 }
diff --git a/shaders_inc/RenderPBR.vsh.h b/shaders_inc/RenderPBR.vsh.h
index 829f51a8..96b220da 100644
--- a/shaders_inc/RenderPBR.vsh.h
+++ b/shaders_inc/RenderPBR.vsh.h
@@ -93,4 +93,9 @@
 "#if USE_TEXCOORD1\n"
 "    VSOut.UV1      = VSIn.UV1;\n"
 "#endif\n"
+"\n"
+"#ifdef USE_GL_POINT_SIZE\n"
+"    // If gl_PointSize is not defined, points are not rendered in GLES\n"
+"    gl_PointSize = 1.0;\n"
+"#endif\n"
 "}\n"