Merge pull request #11699 from Pokechu22/gl-check-maximum-samples

OpenGL: Check the list of supported AA modes instead of hardcoding

1 files changed, 120 insertions, 7 deletions

diff --git a/Source/Core/VideoBackends/OGL/OGLConfig.cpp b/Source/Core/VideoBackends/OGL/OGLConfig.cpp
index 95998b836b..2695402b63 100644
--- a/Source/Core/VideoBackends/OGL/OGLConfig.cpp
+++ b/Source/Core/VideoBackends/OGL/OGLConfig.cpp
@@ -3,6 +3,11 @@
 
 #include "VideoBackends/OGL/OGLConfig.h"
 
+#include <cstdio>
+#include <string>
+#include <string_view>
+
+#include "Common/Assert.h"
 #include "Common/GL/GLContext.h"
 #include "Common/GL/GLExtensions/GLExtensions.h"
 #include "Common/Logging/LogManager.h"
@@ -10,14 +15,13 @@
 
 #include "Core/Config/GraphicsSettings.h"
 
+#include "VideoBackends/OGL/OGLTexture.h"
+
 #include "VideoCommon/DriverDetails.h"
+#include "VideoCommon/FramebufferManager.h"
 #include "VideoCommon/OnScreenDisplay.h"
 #include "VideoCommon/VideoConfig.h"
 
-#include <cstdio>
-#include <string>
-#include <string_view>
-
 namespace OGL
 {
 void InitDriverInfo()
@@ -537,9 +541,118 @@ bool PopulateConfig(GLContext* m_main_gl_context)
   g_Config.backend_info.bSupportsEarlyZ =
       g_ogl_config.bSupportsImageLoadStore || g_ogl_config.bSupportsConservativeDepth;
 
-  glGetIntegerv(GL_MAX_SAMPLES, &g_ogl_config.max_samples);
-  if (g_ogl_config.max_samples < 1 || !g_ogl_config.bSupportsMSAA)
-    g_ogl_config.max_samples = 1;
+  g_Config.backend_info.AAModes.clear();
+  if (g_ogl_config.bSupportsMSAA)
+  {
+    bool supportsGetInternalFormat =
+        GLExtensions::Supports("VERSION_4_2") || GLExtensions::Supports("VERSION_GLES_3");
+    if (supportsGetInternalFormat)
+    {
+      // Note: GL_TEXTURE_2D_MULTISAMPLE_ARRAY_OES should technically be used for
+      // GL_OES_texture_storage_multisample_2d_array, but both are 0x9102 so it does not matter.
+
+      std::vector<int> color_aa_modes;
+      {
+        GLenum colorInternalFormat = OGLTexture::GetGLInternalFormatForTextureFormat(
+            FramebufferManager::GetEFBColorFormat(), true);
+        GLint num_color_sample_counts = 0;
+        glGetInternalformativ(GL_TEXTURE_2D_MULTISAMPLE_ARRAY, colorInternalFormat,
+                              GL_NUM_SAMPLE_COUNTS, 1, &num_color_sample_counts);
+
+        ASSERT_MSG(VIDEO, num_color_sample_counts >= 0,
+                   "negative GL_NUM_SAMPLE_COUNTS for colors does not make sense: {}",
+                   num_color_sample_counts);
+        color_aa_modes.reserve(num_color_sample_counts + 1);
+        if (num_color_sample_counts > 0)
+        {
+          color_aa_modes.resize(num_color_sample_counts);
+
+          static_assert(sizeof(GLint) == sizeof(u32));
+          glGetInternalformativ(GL_TEXTURE_2D_MULTISAMPLE_ARRAY, colorInternalFormat, GL_SAMPLES,
+                                num_color_sample_counts,
+                                reinterpret_cast<GLint*>(color_aa_modes.data()));
+          ASSERT_MSG(VIDEO, std::is_sorted(color_aa_modes.rbegin(), color_aa_modes.rend()),
+                     "GPU driver didn't return sorted color AA modes: [{}]",
+                     fmt::join(color_aa_modes, ", "));
+        }
+
+        if (color_aa_modes.empty() || color_aa_modes.back() != 1)
+          color_aa_modes.push_back(1);
+      }
+
+      std::vector<int> depth_aa_modes;
+      {
+        GLenum depthInternalFormat = OGLTexture::GetGLInternalFormatForTextureFormat(
+            FramebufferManager::GetEFBColorFormat(), true);
+        GLint num_depth_sample_counts = 0;
+        glGetInternalformativ(GL_TEXTURE_2D_MULTISAMPLE_ARRAY, depthInternalFormat,
+                              GL_NUM_SAMPLE_COUNTS, 1, &num_depth_sample_counts);
+
+        ASSERT_MSG(VIDEO, num_depth_sample_counts >= 0,
+                   "negative GL_NUM_SAMPLE_COUNTS for depth does not make sense: {}",
+                   num_depth_sample_counts);
+        depth_aa_modes.reserve(num_depth_sample_counts + 1);
+        if (num_depth_sample_counts > 0)
+        {
+          depth_aa_modes.resize(num_depth_sample_counts);
+
+          static_assert(sizeof(GLint) == sizeof(u32));
+          glGetInternalformativ(GL_TEXTURE_2D_MULTISAMPLE_ARRAY, depthInternalFormat, GL_SAMPLES,
+                                num_depth_sample_counts,
+                                reinterpret_cast<GLint*>(depth_aa_modes.data()));
+          ASSERT_MSG(VIDEO, std::is_sorted(depth_aa_modes.rbegin(), depth_aa_modes.rend()),
+                     "GPU driver didn't return sorted depth AA modes: [{}]",
+                     fmt::join(depth_aa_modes, ", "));
+        }
+
+        if (depth_aa_modes.empty() || depth_aa_modes.back() != 1)
+          depth_aa_modes.push_back(1);
+      }
+
+      // The spec says supported sample formats are returned in descending numeric order.
+      // It also says "Only positive values are returned", but does not specify whether 1 is
+      // included or not; it seems like NVIDIA and Intel GPUs do not include it.
+      // We've inserted 1 at the back of both if not present to handle this.
+      g_Config.backend_info.AAModes.clear();
+      g_Config.backend_info.AAModes.reserve(std::min(color_aa_modes.size(), depth_aa_modes.size()));
+      // We only want AA modes that are supported for both the color and depth textures. Probably
+      // the support is the same, though. rbegin/rend are used to swap the order ahead of time.
+      std::set_intersection(color_aa_modes.rbegin(), color_aa_modes.rend(), depth_aa_modes.rbegin(),
+                            depth_aa_modes.rend(),
+                            std::back_inserter(g_Config.backend_info.AAModes));
+    }
+    else
+    {
+      // The documentation for glGetInternalformativ says its value is at least the minimum of
+      // GL_MAX_SAMPLES, GL_MAX_COLOR_TEXTURE_SAMPLES, and GL_MAX_DEPTH_TEXTURE_SAMPLES (and
+      // GL_MAX_INTEGER_SAMPLES for integer textures, assumed not applicable here).
+      GLint max_color_samples = 0;
+      glGetIntegerv(GL_MAX_COLOR_TEXTURE_SAMPLES, &max_color_samples);
+      GLint max_depth_samples = 0;
+      glGetIntegerv(GL_MAX_COLOR_TEXTURE_SAMPLES, &max_depth_samples);
+      // Note: The desktop OpenGL ref pages don't actually say that GL_MAX_SAMPLES is a valid
+      // parameter for glGetIntegerv (though the ES ones do). However, MAX_SAMPLES is
+      // referenced in the GL 3.1 spec and by GL_ARB_texture_multisample (which is written against
+      // the OpenGL 3.1 spec), so presumably it is valid.
+      GLint max_samples = 0;
+      glGetIntegerv(GL_MAX_SAMPLES, &max_samples);
+      u32 supported_max_samples =
+          static_cast<u32>(std::min({max_samples, max_color_samples, max_depth_samples}));
+
+      while (supported_max_samples > 1)
+      {
+        g_Config.backend_info.AAModes.push_back(supported_max_samples);
+        supported_max_samples /= 2;
+      }
+      g_Config.backend_info.AAModes.push_back(1);
+      // The UI wants ascending order
+      std::reverse(g_Config.backend_info.AAModes.begin(), g_Config.backend_info.AAModes.end());
+    }
+  }
+  else
+  {
+    g_Config.backend_info.AAModes = {1};
+  }
 
   const bool bSupportsIsHelperInvocation = g_ogl_config.bIsES ?
                                                g_ogl_config.eSupportedGLSLVersion >= GlslEs320 :