From e8199a5c4d8c7218178db809bbfc0464f49714b1 Mon Sep 17 00:00:00 2001
From: Laszlo Agocs <laszlo.agocs@qt.io>
Date: Thu, 9 Jan 2020 15:28:54 +0100
Subject: [PATCH] rhi: Add R16F and R32F

Can be relevant for Qt Quick 3D shadows, where the shadow map is R16F.

Task-number: QTBUG-81268
Change-Id: Ic33e100929e133d1cbe0b062a15697c82536f62a
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>
---
 src/gui/rhi/qrhi.cpp       |  6 ++++++
 src/gui/rhi/qrhi_p.h       |  2 ++
 src/gui/rhi/qrhid3d11.cpp  |  4 ++++
 src/gui/rhi/qrhigles2.cpp  | 24 ++++++++++++++++++++++++
 src/gui/rhi/qrhimetal.mm   |  4 ++++
 src/gui/rhi/qrhivulkan.cpp |  4 ++++
 6 files changed, 44 insertions(+)

diff --git a/src/gui/rhi/qrhi.cpp b/src/gui/rhi/qrhi.cpp
index 00d4df53bdd..d2c8ae104e0 100644
--- a/src/gui/rhi/qrhi.cpp
+++ b/src/gui/rhi/qrhi.cpp
@@ -3939,6 +3939,12 @@ void QRhiImplementation::textureFormatInfo(QRhiTexture::Format format, const QSi
     case QRhiTexture::RGBA32F:
         bpc = 16;
         break;
+    case QRhiTexture::R16F:
+        bpc = 2;
+        break;
+    case QRhiTexture::R32F:
+        bpc = 4;
+        break;
 
     case QRhiTexture::D16:
         bpc = 2;
diff --git a/src/gui/rhi/qrhi_p.h b/src/gui/rhi/qrhi_p.h
index a6c65aac5e9..3a64835c22a 100644
--- a/src/gui/rhi/qrhi_p.h
+++ b/src/gui/rhi/qrhi_p.h
@@ -728,6 +728,8 @@ public:
 
         RGBA16F,
         RGBA32F,
+        R16F,
+        R32F,
 
         D16,
         D32F,
diff --git a/src/gui/rhi/qrhid3d11.cpp b/src/gui/rhi/qrhid3d11.cpp
index e58ce880951..445d1625957 100644
--- a/src/gui/rhi/qrhid3d11.cpp
+++ b/src/gui/rhi/qrhid3d11.cpp
@@ -1102,6 +1102,10 @@ static inline DXGI_FORMAT toD3DTextureFormat(QRhiTexture::Format format, QRhiTex
         return DXGI_FORMAT_R16G16B16A16_FLOAT;
     case QRhiTexture::RGBA32F:
         return DXGI_FORMAT_R32G32B32A32_FLOAT;
+    case QRhiTexture::R16F:
+        return DXGI_FORMAT_R16_FLOAT;
+    case QRhiTexture::R32F:
+        return DXGI_FORMAT_R32_FLOAT;
 
     case QRhiTexture::D16:
         return DXGI_FORMAT_R16_TYPELESS;
diff --git a/src/gui/rhi/qrhigles2.cpp b/src/gui/rhi/qrhigles2.cpp
index 24ae0a37403..afa3a397e60 100644
--- a/src/gui/rhi/qrhigles2.cpp
+++ b/src/gui/rhi/qrhigles2.cpp
@@ -165,6 +165,14 @@ QT_BEGIN_NAMESPACE
 #define GL_RGBA16F                        0x881A
 #endif
 
+#ifndef GL_R16F
+#define GL_R16F                           0x822D
+#endif
+
+#ifndef GL_R32F
+#define GL_R32F                           0x822E
+#endif
+
 #ifndef GL_HALF_FLOAT
 #define GL_HALF_FLOAT                     0x140B
 #endif
@@ -697,6 +705,10 @@ bool QRhiGles2::isTextureFormatSupported(QRhiTexture::Format format, QRhiTexture
     case QRhiTexture::RGBA32F:
         return caps.floatFormats;
 
+    case QRhiTexture::R16F:
+    case QRhiTexture::R32F:
+        return caps.floatFormats;
+
     default:
         break;
     }
@@ -3384,6 +3396,18 @@ bool QGles2Texture::prepareBuild(QSize *adjustedSize)
             glformat = GL_RGBA;
             gltype = GL_FLOAT;
             break;
+        case QRhiTexture::R16F:
+            glintformat = GL_R16F;
+            glsizedintformat = glintformat;
+            glformat = GL_RED;
+            gltype = GL_HALF_FLOAT;
+            break;
+        case QRhiTexture::R32F:
+            glintformat = GL_R32F;
+            glsizedintformat = glintformat;
+            glformat = GL_RED;
+            gltype = GL_FLOAT;
+            break;
         case QRhiTexture::D16:
             glintformat = GL_DEPTH_COMPONENT16;
             glsizedintformat = glintformat;
diff --git a/src/gui/rhi/qrhimetal.mm b/src/gui/rhi/qrhimetal.mm
index 53422470e8c..883d6923b93 100644
--- a/src/gui/rhi/qrhimetal.mm
+++ b/src/gui/rhi/qrhimetal.mm
@@ -2320,6 +2320,10 @@ static inline MTLPixelFormat toMetalTextureFormat(QRhiTexture::Format format, QR
         return MTLPixelFormatRGBA16Float;
     case QRhiTexture::RGBA32F:
         return MTLPixelFormatRGBA32Float;
+    case QRhiTexture::R16F:
+        return MTLPixelFormatR16Float;
+    case QRhiTexture::R32F:
+        return MTLPixelFormatR32Float;
 
     case QRhiTexture::D16:
 #ifdef Q_OS_MACOS
diff --git a/src/gui/rhi/qrhivulkan.cpp b/src/gui/rhi/qrhivulkan.cpp
index 2c9249e9116..c4f56f2dd26 100644
--- a/src/gui/rhi/qrhivulkan.cpp
+++ b/src/gui/rhi/qrhivulkan.cpp
@@ -767,6 +767,10 @@ static inline VkFormat toVkTextureFormat(QRhiTexture::Format format, QRhiTexture
         return VK_FORMAT_R16G16B16A16_SFLOAT;
     case QRhiTexture::RGBA32F:
         return VK_FORMAT_R32G32B32A32_SFLOAT;
+    case QRhiTexture::R16F:
+        return VK_FORMAT_R16_SFLOAT;
+    case QRhiTexture::R32F:
+        return VK_FORMAT_R32_SFLOAT;
 
     case QRhiTexture::D16:
         return VK_FORMAT_D16_UNORM;