Mesa 23.1.4 driver workaround path - disables morphing and changes us…

…age of gl_MultiTexCoord0 in the precense of the offending driver version - investigation in progress

src/osgEarth/Capabilities

@@ -24,13 +24,12 @@
 #define OSGEARTH_CAPABILITIES_H 1
 
 #include <osgEarth/Common>
+#include <osgEarth/Version>
 #include <osg/Uniform>
 #include <osg/Texture>
 
 namespace osgEarth
 {
-    class VirtualProgram;
-
     /**
      * Stores information about the hardware and graphics system capbilities.
      * The osgEarth::Registry stores a singleton Capabilities object that you can
@@ -70,15 +69,21 @@ namespace osgEarth
         /** Are we running OpenGLES? */
         bool isGLES() const { return _isGLES; }
 
-        /** the GPU vendor */
+        //! Reported GL_VENDOR
         const std::string& getVendor() const { return _vendor;}
 
-        /** the GPU renderer */
+        //! Reported GL_RENDERER
         const std::string& getRenderer() const { return _renderer;}
 
-        /** the GPU driver version */
+        //! the GL_VERSION string, which include the GL version, driver vendor, and driver version
         const std::string& getVersion() const { return _version;}
 
+        //! GPU driver version extracted from GL_VERSION
+        const Version& getDriverVersion() const { return _driverVersion; }
+
+        //! GPU driver vendor extracted from GL_VERSION
+        const std::string& getDriverVendor() const { return _driverVendor; }
+
         /** whether the GPU supports DEPTH_PACKED_STENCIL buffer */
         bool supportsDepthPackedStencilBuffer() const { return _supportsDepthPackedStencilBuffer; }
 
@@ -133,6 +138,10 @@ namespace osgEarth
         std::string _vendor;
         std::string _renderer;
         std::string _version;
+
+        std::string _driverVendor;
+        Version _driverVersion;
+
         bool _supportsS3TC;
         bool _supportsPVRTC;
         bool _supportsARBTC;

src/osgEarth/Capabilities.cpp

@@ -258,14 +258,25 @@ Capabilities::Capabilities() :
         _GLSLversion = GL2->glslLanguageVersion;
 
         _vendor = std::string( reinterpret_cast<const char*>(glGetString(GL_VENDOR)) );
-        OE_DEBUG << LC << "GPU Vendor:        " << _vendor << std::endl;
+        OE_INFO << LC << "GL_VENDOR:         " << _vendor << std::endl;
 
         _renderer = std::string( reinterpret_cast<const char*>(glGetString(GL_RENDERER)) );
-        OE_INFO << LC << "GPU Renderer:      " << _renderer << std::endl;
+        OE_INFO << LC << "GL_RENDERER:       " << _renderer << std::endl;
 
         _version = std::string( reinterpret_cast<const char*>(glGetString(GL_VERSION)) );
-        OE_INFO << LC << "GL Context/Driver: " << _version << 
-            " (" << getGLSLVersionInt() << ")" << std::endl;
+        OE_INFO << LC << "GL_VERSION:        " << _version << std::endl;
+        //OE_INFO << LC << "GLSL:             " << getGLSLVersionInt() << std::endl;
+
+        // assemble the driver version if possible.
+        std::vector<std::string> version_tokens;
+        Strings::StringTokenizer parse_glversion(_version, version_tokens, " ", "", false, true);
+        if (version_tokens.size() >= 2)
+        {
+            _driverVendor = version_tokens[1];
+            _driverVersion = parseVersion(version_tokens[2].c_str());
+            //OE_INFO << LC << "GL_VERSION vendor: " << _driverVendor << std::endl;
+            //OE_INFO << LC << "GL_VERSION driver: " << _driverVersion.major << "." << _driverVersion.minor << "." << _driverVersion.patch << std::endl;
+        }
 
         // Detect core profile by investigating GL_CONTEXT_PROFILE_MASK
         if ( GL2->glVersion < 3.2f )

src/osgEarth/ImGui/SystemGUI

@@ -25,6 +25,7 @@
 #include <osgEarth/GLUtils>
 #include <osgEarth/ShaderLoader>
 #include <osgEarth/Registry>
+#include <osgEarth/Capabilities>
 #include <chrono>
 #include <list>
 
@@ -140,6 +141,18 @@ namespace osgEarth
 
                     ImGui::Checkbox("Unref image data after apply",
                         &Registry::instance()->unRefImageDataAfterApply().mutable_value());
+
+                    ImGui::Separator();
+                    if (ImGuiLTable::Begin("caps"))
+                    {
+                        auto& caps = osgEarth::Registry::capabilities();
+                        ImGuiLTable::Text("osgEarth", osgEarthGetVersion());
+                        ImGuiLTable::Text("OSG", osgGetVersion());
+                        ImGuiLTable::Text("GL_VENDOR", caps.getVendor().c_str());
+                        ImGuiLTable::Text("GL_RENDERER", caps.getRenderer().c_str());
+                        ImGuiLTable::Text("GL_VERSION", caps.getVersion().c_str());
+                        ImGuiLTable::End();
+                    }
                 }
                 ImGui::End();
             }

src/osgEarth/Version.cpp

@@ -73,3 +73,10 @@ extern "C" {
     }
 
 }
+
+osgEarth::Version osgEarth::parseVersion(const char* in)
+{
+    osgEarth::Version v;
+    sscanf(in, "%d.%d.%d", &v.major, &v.minor, &v.patch);
+    return v;
+}

src/osgEarth/Version.in

@@ -19,12 +19,32 @@
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 */
-
-#ifndef OSGEARTH_VERSION
-#define OSGEARTH_VERSION 1
+#pragma once
 
 #include <osgEarth/Export>
 
+namespace osgEarth
+{
+    struct Version
+    {
+        int v[3] = { 0, 0, 0 };
+        inline bool lessThan(int major, int minor, int patch) const {
+            return v[0] < major || (v[0] == major && (v[1] < minor || (v[1] == minor && v[2] < patch)));
+        }
+        inline bool lessThanOrEqualTo(int major, int minor, int patch) const {
+            return v[0] < major || (v[0] == major && (v[1] < minor || (v[1] == minor && v[2] <= patch)));
+        }
+        inline bool greaterThan(int major, int minor, int patch) const {
+            return v[0] > major || (v[0] == major && (v[1] > minor || (v[1] == minor && v[2] > patch)));
+        }
+        inline bool greaterThanOrEqualTo(int major, int minor, int patch) const {
+            return v[0] > major || (v[0] == major && (v[1] > minor || (v[1] == minor && v[2] >= patch)));
+        }
+    };
+
+    OSGEARTH_EXPORT Version parseVersion(const char*);
+}
+
 extern "C" {
 
 #define OSGEARTH_MAJOR_VERSION @OSGEARTH_MAJOR_VERSION@
@@ -61,4 +81,3 @@ extern OSGEARTH_EXPORT const char* osgEarthGetLibraryName();
 #define OSGEARTH_VERSION_REVISION 0
 }
 
-#endif

src/osgEarthDrivers/engine_rex/RexEngine.ImageLayer.glsl

@@ -3,6 +3,13 @@
 #pragma vp_location   vertex_view
 #pragma vp_order      0.4
 
+#pragma import_defines(OE_MESA_23_WORKAROUND)
+#ifdef OE_MESA_23_WORKAROUND
+    #define TILE_COORDS gl_MultiTexCoord0
+#else
+    #define TILE_COORDS oe_layer_tilec
+#endif
+
 // Stage globals
 vec4 oe_layer_tilec;
 vec2 oe_layer_texc;
@@ -14,8 +21,8 @@ uniform mat4 oe_layer_texParentMatrix;
 void oe_rex_imageLayer_VS(inout vec4 vertexView)
 {
     // calculate the texture coordinates:
-    oe_layer_texc = (oe_layer_texMatrix * oe_layer_tilec).st;
-    oe_layer_texcParent = (oe_layer_texParentMatrix * oe_layer_tilec).st;
+    oe_layer_texc = (oe_layer_texMatrix * TILE_COORDS).st;
+    oe_layer_texcParent = (oe_layer_texParentMatrix * TILE_COORDS).st;
 }
 
 

src/osgEarthDrivers/engine_rex/RexEngine.SDK.glsl

@@ -1,5 +1,12 @@
 #pragma vp_name Rex Terrain SDK
 
+#pragma import_defines(OE_MESA_23_WORKAROUND)
+#ifdef OE_MESA_23_WORKAROUND
+#define TILE_COORDS gl_MultiTexCoord0
+#else
+#define TILE_COORDS oe_layer_tilec
+#endif
+
 uniform sampler2D oe_tile_elevationTex;
 uniform mat4 oe_tile_elevationTexMatrix;
 uniform sampler2D oe_tile_normalTex;
@@ -31,7 +38,7 @@ float oe_terrain_getElevation(in vec2 uv)
 // Read the elevation at the build-in tile coordinates (convenience)
 float oe_terrain_getElevation()
 {
-    return oe_terrain_getElevation(oe_layer_tilec.st);
+    return oe_terrain_getElevation(TILE_COORDS.st);
 }
 
 // Read the normal vector and curvature at resolved UV tile coordinates.
@@ -50,7 +57,7 @@ vec4 oe_terrain_getNormalAndCurvature(in vec2 uv_scaledBiased)
 
 vec4 oe_terrain_getNormalAndCurvature()
 {
-    vec2 uv_scaledBiased = oe_layer_tilec.st
+    vec2 uv_scaledBiased = TILE_COORDS.st
         * oe_tile_elevTexelCoeff.x * oe_tile_normalTexMatrix[0][0]
         + oe_tile_elevTexelCoeff.x * oe_tile_normalTexMatrix[3].st
         + oe_tile_elevTexelCoeff.y;

src/osgEarthDrivers/engine_rex/RexTerrainEngineNode.cpp

@@ -260,6 +260,18 @@ RexTerrainEngineNode::onSetMap()
         _morphingSupported = false;
     }
 
+    // There is an (apparent) bug in the mesa 23.1.4 driver that causes display artifacts 
+    // when doing morphing; this code will attempt to detect that condition and disable
+    // the offending code until we can find a workaround.
+    auto vendor = Registry::capabilities().getDriverVendor();
+    auto version = Registry::capabilities().getDriverVersion();
+    if (vendor == "Mesa" && version.greaterThanOrEqualTo(23, 1, 4))
+    {
+        OE_WARN << LC << "Detected Mesa >= 23.1.4 driver; disabling terrain & imagery morphing" << std::endl;
+        _morphingSupported = false;
+        getOrCreateStateSet()->setDefine("OE_MESA_23_WORKAROUND");
+    }
+
     // morphing imagery LODs requires we bind parent textures to their own unit.
     if (options.getMorphImagery() && _morphingSupported)
     {