Merge pull request #1740 from nikolaykasyanov/software-cursor-decompression

Decompress cursors using SDL software renderer on Mac or if OSG >= 3.5.8 or if OPENMW_DECOMPRESS_TEXTURES is set

Author: psi29a

CHANGELOG.md

@@ -86,6 +86,7 @@
     Bug #4412: openmw-iniimporter ignores data paths from config
     Bug #4413: Moving with 0 strength uses all of your fatigue
     Bug #4420: Camera flickering when I open up and close menus while sneaking
+    Bug #4424: [macOS] Cursor is either empty or garbage when compiled against macOS 10.13 SDK
     Bug #4435: Item health is considered a signed integer
     Bug #4441: Adding items to currently disabled weapon-wielding creatures crashes the game
     Feature #1786: Round up encumbrance value in the encumbrance bar

apps/openmw/engine.cpp

@@ -428,9 +428,8 @@ void OMW::Engine::setWindowIcon()
     else
     {
         osg::ref_ptr<osg::Image> image = result.getImage();
-        SDL_Surface* surface = SDLUtil::imageToSurface(image, true);
-        SDL_SetWindowIcon(mWindow, surface);
-        SDL_FreeSurface(surface);
+        auto surface = SDLUtil::imageToSurface(image, true);
+        SDL_SetWindowIcon(mWindow, surface.get());
     }
 }
 

components/sdlutil/imagetosurface.cpp

@@ -6,7 +6,7 @@
 namespace SDLUtil
 {
 
-SDL_Surface* imageToSurface(osg::Image *image, bool flip)
+SurfaceUniquePtr imageToSurface(osg::Image *image, bool flip)
 {
     int width = image->s();
     int height = image->t();
@@ -22,7 +22,7 @@ SDL_Surface* imageToSurface(osg::Image *image, bool flip)
                 static_cast<Uint8>(clr.g() * 255), static_cast<Uint8>(clr.b() * 255), static_cast<Uint8>(clr.a() * 255));
         }
 
-    return surface;
+    return SurfaceUniquePtr(surface, SDL_FreeSurface);
 }
 
 }

components/sdlutil/imagetosurface.hpp

@@ -1,6 +1,8 @@
 #ifndef OPENMW_COMPONENTS_SDLUTIL_IMAGETOSURFACE_H
 #define OPENMW_COMPONENTS_SDLUTIL_IMAGETOSURFACE_H
 
+#include <memory>
+
 struct SDL_Surface;
 
 namespace osg
@@ -10,10 +12,10 @@ namespace osg
 
 namespace SDLUtil
 {
+    typedef std::unique_ptr<SDL_Surface, void (*)(SDL_Surface *)> SurfaceUniquePtr;
 
     /// Convert an osg::Image to an SDL_Surface.
-    /// @note The returned surface must be freed using SDL_FreeSurface.
-    SDL_Surface* imageToSurface(osg::Image* image, bool flip=false);
+    SurfaceUniquePtr imageToSurface(osg::Image* image, bool flip=false);
 
 }
 

components/sdlutil/sdlcursormanager.cpp

@@ -7,11 +7,14 @@
 
 #include <SDL_mouse.h>
 #include <SDL_endian.h>
+#include <SDL_render.h>
+#include <SDL_hints.h>
 
 #include <osg/GraphicsContext>
 #include <osg/Geometry>
 #include <osg/Texture2D>
 #include <osg/TexMat>
+#include <osg/Version>
 #include <osgViewer/GraphicsWindow>
 
 #include "imagetosurface.hpp"
@@ -22,8 +25,14 @@
 USE_GRAPHICSWINDOW()
 #endif
 
-namespace
+namespace CursorDecompression
 {
+    // macOS builds use the OSG fork that includes DXTC commit
+    #if OSG_VERSION_GREATER_OR_EQUAL(3, 5, 8) || defined(__APPLE__)
+    static const bool DXTCSupported = true;
+    #else
+    static const bool DXTCSupported = false;
+    #endif
 
     class MyGraphicsContext {
         public:
@@ -80,10 +89,8 @@ namespace
             osg::ref_ptr<osg::GraphicsContext> _gc;
     };
 
-    osg::ref_ptr<osg::Image> decompress (osg::ref_ptr<osg::Image> source, float rotDegrees)
+    SDLUtil::SurfaceUniquePtr hardwareDecompress (osg::ref_ptr<osg::Image> source, float rotDegrees)
     {
-        // TODO: use software decompression once S3TC patent expires
-
         int width = source->s();
         int height = source->t();
 
@@ -132,17 +139,6 @@ namespace
 
         osg::ref_ptr<osg::Geometry> geom;
 
-#if defined(__APPLE__)
-        // Extra flip needed on OS X systems due to a driver bug
-        const char* envval = getenv("OPENMW_CURSOR_WORKAROUND");
-        bool workaround = !envval || envval == std::string("1");
-        std::string vendorString = (const char*)glGetString(GL_VENDOR);
-        if (!envval)
-            workaround = vendorString.find("Intel") != std::string::npos || vendorString.find("ATI") != std::string::npos || vendorString.find("AMD") != std::string::npos;
-        if (workaround)
-            geom = osg::createTexturedQuadGeometry(osg::Vec3(-1,1,0), osg::Vec3(2,0,0), osg::Vec3(0,-2,0));
-        else
-#endif
         geom = osg::createTexturedQuadGeometry(osg::Vec3(-1,-1,0), osg::Vec3(2,0,0), osg::Vec3(0,2,0));
 
         geom->drawImplementation(renderInfo);
@@ -153,7 +149,52 @@ namespace
         source->releaseGLObjects();
         texture->releaseGLObjects();
 
-        return resultImage;
+        return SDLUtil::imageToSurface(resultImage, true);
+    }
+
+    SDLUtil::SurfaceUniquePtr softwareDecompress (osg::ref_ptr<osg::Image> source, float rotDegrees)
+    {
+        int width = source->s();
+        int height = source->t();
+        bool useAlpha = source->isImageTranslucent();
+
+        osg::ref_ptr<osg::Image> decompressedImage = new osg::Image;
+        decompressedImage->setFileName(source->getFileName());
+        decompressedImage->allocateImage(width, height, 1, useAlpha ? GL_RGBA : GL_RGB, GL_UNSIGNED_BYTE);
+        for (int s=0; s<width; ++s)
+            for (int t=0; t<height; ++t)
+                decompressedImage->setColor(source->getColor(s,t,0), s,t,0);
+
+        Uint32 redMask = 0x000000ff;
+        Uint32 greenMask = 0x0000ff00;
+        Uint32 blueMask = 0x00ff0000;
+        Uint32 alphaMask = useAlpha ? 0xff000000 : 0;
+
+        SDL_Surface *cursorSurface = SDL_CreateRGBSurfaceFrom(decompressedImage->data(),
+            width,
+            height,
+            decompressedImage->getPixelSizeInBits(),
+            decompressedImage->getRowSizeInBytes(),
+            redMask,
+            greenMask,
+            blueMask,
+            alphaMask);
+
+        SDL_Surface *targetSurface = SDL_CreateRGBSurface(0, width, height, 32, redMask, greenMask, blueMask, alphaMask);
+        SDL_Renderer *renderer = SDL_CreateSoftwareRenderer(targetSurface);
+
+        SDL_RenderClear(renderer);
+
+        SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, "1");
+        SDL_Texture *cursorTexture = SDL_CreateTextureFromSurface(renderer, cursorSurface);
+
+        SDL_RenderCopyEx(renderer, cursorTexture, NULL, NULL, -rotDegrees, NULL, SDL_FLIP_VERTICAL);
+
+        SDL_DestroyTexture(cursorTexture);
+        SDL_FreeSurface(cursorSurface);
+        SDL_DestroyRenderer(renderer);
+
+        return SDLUtil::SurfaceUniquePtr(targetSurface, SDL_FreeSurface);
     }
 
 }
@@ -222,27 +263,30 @@ namespace SDLUtil
 
     void SDLCursorManager::_createCursorFromResource(const std::string& name, int rotDegrees, osg::Image* image, Uint8 hotspot_x, Uint8 hotspot_y)
     {
-        osg::ref_ptr<osg::Image> decompressed;
-
         if (mCursorMap.find(name) != mCursorMap.end())
             return;
 
+        static bool forceSoftwareDecompression = (getenv("OPENMW_DECOMPRESS_TEXTURES") != 0);
+
+        SurfaceUniquePtr (*decompressionFunction)(osg::ref_ptr<osg::Image>, float);
+        if (forceSoftwareDecompression || CursorDecompression::DXTCSupported) {
+            decompressionFunction = CursorDecompression::softwareDecompress;
+        } else {
+            decompressionFunction = CursorDecompression::hardwareDecompress;
+        }
+
         try {
-            decompressed = decompress(image, static_cast<float>(rotDegrees));
+            auto surface = decompressionFunction(image, static_cast<float>(rotDegrees));
+
+            //set the cursor and store it for later
+            SDL_Cursor* curs = SDL_CreateColorCursor(surface.get(), hotspot_x, hotspot_y);
+
+            mCursorMap.insert(CursorMap::value_type(std::string(name), curs));
         } catch (std::exception& e) {
             std::cerr << e.what() << std::endl;
             std::cerr <<"Using default cursor."<<std::endl;
             return;
         }
-
-        SDL_Surface* surf = SDLUtil::imageToSurface(decompressed, true);
-
-        //set the cursor and store it for later
-        SDL_Cursor* curs = SDL_CreateColorCursor(surf, hotspot_x, hotspot_y);
-        mCursorMap.insert(CursorMap::value_type(std::string(name), curs));
-
-        //clean up
-        SDL_FreeSurface(surf);
     }
 
 }