]>
Dogcows Code - chaz/yoink/blob - src/Moof/Texture.cc
2 /*******************************************************************************
4 Copyright (c) 2009, Charles McGarvey
7 Redistribution and use in source and binary forms, with or without
8 modification, are permitted provided that the following conditions are met:
10 * Redistributions of source code must retain the above copyright notice,
11 this list of conditions and the following disclaimer.
12 * Redistributions in binary form must reproduce the above copyright notice,
13 this list of conditions and the following disclaimer in the documentation
14 and/or other materials provided with the distribution.
16 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
20 FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
23 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *******************************************************************************/
29 #include <cstring> // memcpy
31 #include <boost/bind.hpp>
34 #include <SDL/SDL_image.h>
36 #include "Dispatcher.hh"
37 #include "Exception.hh"
48 * The texture implementation just contains all the information about the image
49 * which is worth having in memory. The image data itself is not worth keeping
50 * in memory if the texture has been loaded to GL, but the name of the resource
51 * is retained so that it can be reloaded if necessary. The implementation is a
52 * mippleton so that multiple texture objects can share the same internal
53 * objects and avoid having duplicate textures loaded to GL.
56 class Texture::Impl
: public Library
<Impl
>
60 * Delete the texture (if it is loaded) from GL.
67 if (mObject
== globalObject_
)
72 glDeleteTextures(1, &mObject
);
78 * If the GL context was recreated, we need to reload the texture. This may
79 * involve reading it from disk again, but hopefully the OS was smart enough
80 * to cache it if the client has plenty of RAM.
83 void contextRecreated(const Notification
* note
)
85 mObject
= globalObject_
= 0;
90 * This is a helper method used by some of the texture loading code. It
91 * returns the first power of two which is greater than the input value.
94 static int powerOfTwo(int input
)
106 static void flipSurface(SDL_Surface
* image
)
108 unsigned char* pixels
= (Uint8
*)(image
->pixels
);
110 unsigned pitch
= image
->pitch
;
111 unsigned char line
[pitch
];
114 int yEnd
= image
->h
- 1;
116 if (SDL_MUSTLOCK(image
)) SDL_LockSurface(image
);
117 while (yBegin
< yEnd
)
119 memcpy(line
, pixels
+ pitch
* yBegin
, pitch
);
120 memcpy(pixels
+ pitch
* yBegin
, pixels
+ pitch
* yEnd
, pitch
);
121 memcpy(pixels
+ pitch
* yEnd
, line
, pitch
);
125 if (SDL_MUSTLOCK(image
)) SDL_UnlockSurface(image
);
131 * Construction is initialization.
134 explicit Impl(const std::string
& name
) :
140 mMinFilter(GL_NEAREST
),
141 mMagFilter(GL_NEAREST
),
148 // we want to know when the GL context is recreated
149 Dispatcher::getInstance().addHandler("video.context_recreated",
150 boost::bind(&Impl::contextRecreated
, this, _1
), this);
157 SDL_FreeSurface(mContext
);
162 Dispatcher::getInstance().removeHandler(this);
167 * Adapted from some public domain code. This stuff is common enough that
168 * it really should be included in SDL_image... We need this because images
169 * loaded with SDL_image aren't exactly GL-ready right out of the box. This
170 * method makes them ready.
173 static SDL_Surface
* prepareImageForGL(SDL_Surface
* surface
)
175 int w
= powerOfTwo(surface
->w
);
176 int h
= powerOfTwo(surface
->h
);
178 // 2. OpenGL textures make more sense within the coordinate system when
179 // they are "upside down," so let's flip it.
181 flipSurface(surface
);
183 // 1. OpenGL images must (generally) have dimensions of a power-of-two.
184 // If this one doesn't, we can at least be more friendly by expanding
185 // the dimensions so that they are, though there will be some empty
186 // space within the range of normal texture coordinates. It's better if
187 // textures are the right size to begin with.
189 SDL_Surface
* image
= SDL_CreateRGBSurface
194 #if SDL_BYTEORDER == SDL_LIL_ENDIAN
212 Uint32 savedFlags
= surface
->flags
&(SDL_SRCALPHA
|SDL_RLEACCELOK
);
213 Uint8 savedAlpha
= surface
->format
->alpha
;
214 if (savedFlags
& SDL_SRCALPHA
)
216 SDL_SetAlpha(surface
, 0, 0);
219 SDL_Rect srcArea
, destArea
;
220 srcArea
.x
= 0; destArea
.x
= 0;
221 srcArea
.y
= 0; destArea
.y
= h
- surface
->h
;
222 srcArea
.w
= surface
->w
;
223 srcArea
.h
= surface
->h
;
224 SDL_BlitSurface(surface
, &srcArea
, image
, &destArea
);
226 if (savedFlags
& SDL_SRCALPHA
)
228 SDL_SetAlpha(surface
, savedFlags
, savedAlpha
);
235 * Use SDL_image to load images from file. A surface with the image data is
237 * @return Image data.
242 SDL_Surface
* surface
;
244 surface
= IMG_Load(Texture::getPath(getName()).c_str());
248 logWarning("texture not found: %s", getName().c_str());
249 throw Exception(ErrorCode::FILE_NOT_FOUND
, getName().c_str());
252 SDL_Surface
* temp
= prepareImageForGL(surface
);
253 SDL_FreeSurface(surface
);
257 throw Exception(ErrorCode::UNKNOWN_IMAGE_FORMAT
);
260 if (temp
->format
->BytesPerPixel
== 3)
264 else if (temp
->format
->BytesPerPixel
== 4)
270 SDL_FreeSurface(temp
);
271 throw Exception(ErrorCode::UNKNOWN_IMAGE_FORMAT
);
282 * Upload the image to GL so that it will be accessible by a much more
283 * manageable handle and hopefully reside in video memory.
294 if (!mContext
) loadFromFile();
296 glGenTextures(1, &mObject
);
297 glBindTexture(GL_TEXTURE_2D
, mObject
);
316 SDL_FreeSurface(mContext
);
322 * Sets some texture properties such as the filters and external coordinate
328 glTexParameteri(GL_TEXTURE_2D
, GL_TEXTURE_MIN_FILTER
, mMinFilter
);
329 glTexParameteri(GL_TEXTURE_2D
, GL_TEXTURE_MAG_FILTER
, mMagFilter
);
330 glTexParameteri(GL_TEXTURE_2D
, GL_TEXTURE_WRAP_S
, mWrapS
);
331 glTexParameteri(GL_TEXTURE_2D
, GL_TEXTURE_WRAP_T
, mWrapT
);
334 inline void setMinFilter(GLuint filter
)
338 glTexParameteri(GL_TEXTURE_2D
, GL_TEXTURE_MIN_FILTER
, mMinFilter
);
341 inline void setMagFilter(GLuint filter
)
345 glTexParameteri(GL_TEXTURE_2D
, GL_TEXTURE_MAG_FILTER
, mMagFilter
);
348 inline void setWrapS(GLuint wrap
)
352 glTexParameteri(GL_TEXTURE_2D
, GL_TEXTURE_WRAP_S
, mWrapS
);
355 inline void setWrapT(GLuint wrap
)
359 glTexParameteri(GL_TEXTURE_2D
, GL_TEXTURE_WRAP_T
, mWrapT
);
369 if (mObject
!= globalObject_
)
371 glBindTexture(GL_TEXTURE_2D
, mObject
);
372 globalObject_
= mObject
;
377 SDL_Surface
* mContext
;
378 unsigned mWidth
; ///< Horizontal dimension of the image.
379 unsigned mHeight
; ///< Vertical dimension.
381 GLuint mMode
; ///< Depth of the image, GL_RGB or GL_RGBA.
382 GLuint mMinFilter
; ///< Minifcation filter.
383 GLuint mMagFilter
; ///< Magnification filter.
384 GLuint mWrapS
; ///< Wrapping behavior horizontally.
385 GLuint mWrapT
; ///< Wrapping behavior vertically.
387 GLuint mObject
; ///< GL texture handle.
388 static GLuint globalObject_
; ///< Global GL texture handle.
391 GLuint
Texture::Impl::globalObject_
= 0;
394 Texture::Texture(const std::string
& name
) :
396 mImpl(Texture::Impl::getInstance(name
)) {}
400 * Bind the GL texture for mapping, etc.
403 void Texture::bind() const
411 * Get the texture object, for the curious.
414 GLuint
Texture::getObject() const
417 return mImpl
->mObject
;
421 void Texture::resetBind()
423 glBindTexture(GL_TEXTURE_2D
, 0);
424 Impl::globalObject_
= 0;
428 unsigned Texture::getWidth() const
431 return mImpl
->mWidth
;
434 unsigned Texture::getHeight() const
437 return mImpl
->mHeight
;
441 void Texture::setMinFilter(GLuint filter
)
444 mImpl
->setMinFilter(filter
);
447 void Texture::setMagFilter(GLuint filter
)
450 mImpl
->setMagFilter(filter
);
453 void Texture::setWrapS(GLuint wrap
)
456 mImpl
->setWrapS(wrap
);
459 void Texture::setWrapT(GLuint wrap
)
462 mImpl
->setWrapT(wrap
);
466 std::string
Texture::getPath(const std::string
& name
)
468 std::string path
= Resource::getPath("textures/" + name
+ ".png");
475 /** vim: set ts=4 sw=4 tw=80: *************************************************/
This page took 0.060358 seconds and 4 git commands to generate.