Ticket #4549: nvtt-engine.diff

source/graphics/TextureConverter.cpp

@@ -52 +52 @@
         memcpy(&buffer[off], data, size);
         return true;
     }
+
+    virtual void endImage()
+    {
+    }
 };
 
 /**
@@ -64 +68 @@
     nvtt::InputOptions inputOptions;
     nvtt::CompressionOptions compressionOptions;
     nvtt::OutputOptions outputOptions;
-    bool isDXT1a; // see comment in RunThread
-    bool is8bpp;
 };
 
 /**
@@ -383 +385 @@
     else
         request->inputOptions.setAlphaMode(nvtt::AlphaMode_None);
 
-    request->isDXT1a = false;
-    request->is8bpp = false;
-
     if (settings.format == FMT_RGBA)
     {
         request->compressionOptions.setFormat(nvtt::Format_RGBA);
@@ -396 +395 @@
     {
         request->compressionOptions.setFormat(nvtt::Format_RGBA);
         request->compressionOptions.setPixelFormat(8, 0x00, 0x00, 0x00, 0xFF);
-        request->is8bpp = true;
     }
     else if (!hasAlpha)
     {
@@ -406 +404 @@
     else if (settings.format == FMT_DXT1)
     {
         request->compressionOptions.setFormat(nvtt::Format_DXT1a);
-        request->isDXT1a = true;
     }
     else if (settings.format == FMT_DXT3)
     {
@@ -578 +575 @@
             result->ret = compressor.process(request->inputOptions, request->compressionOptions, request->outputOptions);
         }
 
-        // Ugly hack: NVTT 2.0 doesn't set DDPF_ALPHAPIXELS for DXT1a, so we can't
-        // distinguish it from DXT1. (It's fixed in trunk by
-        // http://code.google.com/p/nvidia-texture-tools/source/detail?r=924&path=/trunk).
-        // Rather than using a trunk NVTT (unstable, makes packaging harder)
-        // or patching our copy (makes packaging harder), we'll just manually
-        // set the flag here.
-        if (request->isDXT1a && result->ret && result->output.buffer.size() > 80)
-            result->output.buffer[80] |= 1; // DDPF_ALPHAPIXELS in DDS_PIXELFORMAT.dwFlags
-        // Ugly hack: NVTT always sets DDPF_RGB, even if we're trying to output 8-bit
-        // alpha-only DDS with no RGB components. Unset that flag.
-        if (request->is8bpp)
-            result->output.buffer[80] &= ~0x40; // DDPF_RGB in DDS_PIXELFORMAT.dwFlags
-
         // Push the result onto the queue
         std::lock_guard<std::mutex> wait_lock(textureConverter->m_WorkerMutex);
         textureConverter->m_ResultQueue.push_back(result);

source/lib/tex/tex_dds.cpp

@@ -310 +310 @@
 
 // DDS_PIXELFORMAT.dwFlags
 // we've seen some DXT3 files that don't have this set (which is nonsense;
-// any image lacking alpha should be stored as DXT1). it's authoritative
-// if fourcc is DXT1 (there's no other way to tell DXT1 and DXT1a apart)
-// and ignored otherwise.
+// any image lacking alpha should be stored as DXT1).
 #define DDPF_ALPHAPIXELS 0x00000001
+// DDPF_ALPHA is used instead of DDPF_ALPHAPIXELS for DXT1a.
+#define DDPF_ALPHA       0x00000002
 #define DDPF_FOURCC      0x00000004
 #define DDPF_RGB         0x00000040
 
@@ -326 +326 @@
     u32 dwRBitMask;
     u32 dwGBitMask;
     u32 dwBBitMask;
-    u32 dwABitMask;                   // (DDPF_ALPHAPIXELS)
+    u32 dwABitMask;                   // (DDPF_ALPHA or DDPF_ALPHAPIXELS)
 };
 
 
@@ -435 +435 @@
         RETURN_STATUS_IF_ERR(tex_validate_plain_format(bpp, (int)flags));
     }
     // .. uncompressed 8bpp greyscale
-    else if(pf_flags & DDPF_ALPHAPIXELS)
+    else if(pf_flags & DDPF_ALPHA)
     {
         const size_t pf_bpp    = (size_t)read_le32(&pf->dwRGBBitCount);
         const size_t pf_a_mask = (size_t)read_le32(&pf->dwABitMask);
@@ -460 +460 @@
         {
         case FOURCC('D','X','T','1'):
             bpp = 4;
-            if(pf_flags & DDPF_ALPHAPIXELS)
+            if(pf_flags & DDPF_ALPHA)
                 flags |= DXT1A | TEX_ALPHA;
             else
                 flags |= 1;