1 /*
2 -----------------------------------------------------------------------------
3 This source file is part of OGRE
4     (Object-oriented Graphics Rendering Engine)
5 For the latest info, see http://www.ogre3d.org/
6 
7 Copyright (c) 2000-2014 Torus Knot Software Ltd
8 
9 Permission is hereby granted, free of charge, to any person obtaining a copy
10 of this software and associated documentation files (the "Software"), to deal
11 in the Software without restriction, including without limitation the rights
12 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13 copies of the Software, and to permit persons to whom the Software is
14 furnished to do so, subject to the following conditions:
15 
16 The above copyright notice and this permission notice shall be included in
17 all copies or substantial portions of the Software.
18 
19 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
22 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25 THE SOFTWARE.
26 -----------------------------------------------------------------------------
27 */
28 
29 #include "OgreGLTextureManager.h"
30 #include "OgreRoot.h"
31 #include "OgreRenderSystem.h"
32 #include "OgreGLCopyingRenderTexture.h"
33 #include "OgreGLTexture.h"
34 #include "OgreGLPixelFormat.h"
35 #include "OgreGLRenderSystem.h"
36 
37 namespace Ogre {
38     //-----------------------------------------------------------------------------
GLTextureManager(GLRenderSystem * renderSystem)39     GLTextureManager::GLTextureManager(GLRenderSystem* renderSystem)
40         : TextureManager(), mRenderSystem(renderSystem)
41     {
42         // register with group manager
43         ResourceGroupManager::getSingleton()._registerResourceManager(mResourceType, this);
44     }
45     //-----------------------------------------------------------------------------
~GLTextureManager()46     GLTextureManager::~GLTextureManager()
47     {
48         // unregister with group manager
49         ResourceGroupManager::getSingleton()._unregisterResourceManager(mResourceType);
50     }
51     //-----------------------------------------------------------------------------
createImpl(const String & name,ResourceHandle handle,const String & group,bool isManual,ManualResourceLoader * loader,const NameValuePairList * createParams)52     Resource* GLTextureManager::createImpl(const String& name, ResourceHandle handle,
53         const String& group, bool isManual, ManualResourceLoader* loader,
54         const NameValuePairList* createParams)
55     {
56         return new GLTexture(this, name, handle, group, isManual, loader, mRenderSystem);
57     }
58 
59     //-----------------------------------------------------------------------------
getNativeFormat(TextureType ttype,PixelFormat format,int usage)60     PixelFormat GLTextureManager::getNativeFormat(TextureType ttype, PixelFormat format, int usage)
61     {
62         // Adjust requested parameters to capabilities
63         const RenderSystemCapabilities *caps = Root::getSingleton().getRenderSystem()->getCapabilities();
64 
65         // Check compressed texture support
66         // if a compressed format not supported, revert to PF_A8R8G8B8
67         if(PixelUtil::isCompressed(format) &&
68             !caps->hasCapability( RSC_TEXTURE_COMPRESSION_DXT ))
69         {
70             return PF_BYTE_RGBA;
71         }
72         // if floating point textures not supported, revert to PF_A8R8G8B8
73         if(PixelUtil::isFloatingPoint(format) &&
74             !caps->hasCapability( RSC_TEXTURE_FLOAT ))
75         {
76             return PF_BYTE_RGBA;
77         }
78 
79         if(GLPixelUtil::getGLInternalFormat(format) == GL_NONE)
80         {
81             return PF_BYTE_RGBA;
82         }
83 
84         // Check if this is a valid rendertarget format
85         if( usage & TU_RENDERTARGET )
86         {
87             /// Get closest supported alternative
88             /// If mFormat is supported it's returned
89             return GLRTTManager::getSingleton().getSupportedAlternative(format);
90         }
91 
92         // Supported
93         return format;
94 
95 
96     }
97     //-----------------------------------------------------------------------------
isHardwareFilteringSupported(TextureType ttype,PixelFormat format,int usage,bool preciseFormatOnly)98     bool GLTextureManager::isHardwareFilteringSupported(TextureType ttype, PixelFormat format, int usage,
99             bool preciseFormatOnly)
100     {
101         // precise format check
102         if (!TextureManager::isHardwareFilteringSupported(ttype, format, usage, preciseFormatOnly))
103             return false;
104 
105         // Assume non-floating point is supported always
106         if (!PixelUtil::isFloatingPoint(getNativeFormat(ttype, format, usage)))
107             return true;
108 
109         // check for floating point extension
110         // note false positives on old harware:
111         // https://www.khronos.org/opengl/wiki/Floating_point_and_mipmapping_and_filtering
112         return mRenderSystem->checkExtension("GL_ARB_texture_float");
113     }
114 
115 }
116