基于NDK的OPENGL程序怎么解码PNG图片文件？必须去移植libpng/cximage类库吗？

xqhrs232 2011-04-14 01:07:26

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xqhrs232 2012-05-28

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[Quote=引用 26 楼的回复:]
LZ 你把mk文件贴出来呗。
我怎么写都是png.h找不到。
[/Quote]
你把PNG。H找到加到android-ndk-r5-windows\android-ndk-r5\platforms\android-8\arch-arm\usr\include就可以了！！！

arpsyalin 2012-05-28

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LZ 你把mk文件贴出来呗。
我怎么写都是png.h找不到。

xqhrs232 2011-04-16

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又出新的错误

The erros of makefile "*** target pattern contains no `%'. Stop."

http://forums.devshed.com/c-programming-42/the-erros-of-makefile-target-pattern-contains-no-stop-546706.html

xqhrs232 2011-04-16

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第十五章 make的常见错误信息

http://www.linuxsir.org/main/doc/gnumake/GNUmake_v3.80-zh_CN_html/make-15.html#_静态模式

qthsrs232 2011-04-16

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整了个老半天，总算把PNG图片解出来了。指针的问题，弄的找了老半天的错误-----函数都执行成功了但没有图片显示出来！！！

qthsrs232 2011-04-16

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[Quote=引用 21 楼 qthsrs232 的回复:]
一段参考代码
如何读取PNG格式文件并在DX中显示？
http://bbs.gameres.com/showthread.asp?postid=95124

C/C++ code

#include "png.h"unsigned char *load_png(FILE *file,int &width,int &height) { png_byte si……
[/Quote]







#include "png.h"unsigned char *load_png(FILE *file,int &width,int &height) 

{

	

png_byte sig[8];	

fread(sig,8,1,file);	

if(!png_check_sig(sig,8)) 

{		

fprintf(stderr,"load_png(): wrong signature\n");		

return NULL;	

}

	

png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);	

if(!png_ptr) 

return NULL;	



png_infop info_ptr = png_create_info_struct(png_ptr);	

if(!info_ptr) 

{		

png_destroy_read_struct(&png_ptr,0,0);		

return NULL;	

}

	

png_init_io(png_ptr,file);	

png_set_sig_bytes(png_ptr,8);	

png_read_info(png_ptr,info_ptr);	





unsigned long w,h;	

int bit_depth,color_type;

	

png_get_IHDR(png_ptr,info_ptr,&w,&h,&bit_depth,&color_type,0,0,0);

	

if(bit_depth == 16) 

png_set_strip_16(png_ptr);	

if(color_type == PNG_COLOR_TYPE_PALETTE) 

png_set_expand(png_ptr);	

if(bit_depth < 8) 

png_set_expand(png_ptr);	

if(png_get_valid(png_ptr,info_ptr,PNG_INFO_tRNS)) 

png_set_expand(png_ptr);	

if(color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_GRAY_ALPHA) png_set_gray_to_rgb(png_ptr);	



double gamma;	

if(png_get_gAMA(png_ptr,info_ptr,&gamma))

 png_set_gamma(png_ptr,(double)2.2,gamma);	

png_read_update_info(png_ptr,info_ptr);	

png_get_IHDR(png_ptr,info_ptr,&w,&h,&bit_depth,&color_type,0,0,0);

	

png_uint_32 row_bytes = png_get_rowbytes(png_ptr,info_ptr);	

png_uint_32 channels = png_get_channels(png_ptr,info_ptr);	



png_byte *img = new png_byte[row_bytes * h];	

png_byte **row = new png_byte*[h];	



for(int i = 0; i < (int)h; i++) 

row[i] = img + row_bytes * i;



	png_read_image(png_ptr,row);	

png_read_end(png_ptr,NULL);	

png_destroy_read_struct(&png_ptr,0,0);	



delete row;	

width = w;	

height = h;	

unsigned char *data = new unsigned char[width * height * 4];	

unsigned char *ptr = data;	

for(int i = 0; i < height; i++) 

{		

for(int j = 0; j < width; j++) 

{			

int k = row_bytes * i + j * channels;			

*ptr++ = img[k + 0];			

*ptr++ = img[k + 1];			

*ptr++ = img[k + 2];			

if(channels == 4)

 *ptr++ = img[k + 3];			

else *ptr++ = 255;		

}	

}	

delete img;	

return data;

}

qthsrs232 2011-04-16

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一段参考代码
如何读取PNG格式文件并在DX中显示？
http://bbs.gameres.com/showthread.asp?postid=95124





#include "png.h"unsigned char *load_png(FILE *file,int &width,int &height) {	png_byte sig[8];	fread(sig,8,1,file);	if(!png_check_sig(sig,8)) {		fprintf(stderr,"load_png(): wrong signature\n");		return NULL;	}	png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);	if(!png_ptr) return NULL;	png_infop info_ptr = png_create_info_struct(png_ptr);	if(!info_ptr) {		png_destroy_read_struct(&png_ptr,0,0);		return NULL;	}	png_init_io(png_ptr,file);	png_set_sig_bytes(png_ptr,8);	png_read_info(png_ptr,info_ptr);	unsigned long w,h;	int bit_depth,color_type;	png_get_IHDR(png_ptr,info_ptr,&w,&h,&bit_depth,&color_type,0,0,0);	if(bit_depth == 16) png_set_strip_16(png_ptr);	if(color_type == PNG_COLOR_TYPE_PALETTE) png_set_expand(png_ptr);	if(bit_depth < 8) png_set_expand(png_ptr);	if(png_get_valid(png_ptr,info_ptr,PNG_INFO_tRNS)) png_set_expand(png_ptr);	if(color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_GRAY_ALPHA) png_set_gray_to_rgb(png_ptr);	double gamma;	if(png_get_gAMA(png_ptr,info_ptr,&gamma)) png_set_gamma(png_ptr,(double)2.2,gamma);	png_read_update_info(png_ptr,info_ptr);	png_get_IHDR(png_ptr,info_ptr,&w,&h,&bit_depth,&color_type,0,0,0);	png_uint_32 row_bytes = png_get_rowbytes(png_ptr,info_ptr);	png_uint_32 channels = png_get_channels(png_ptr,info_ptr);	png_byte *img = new png_byte[row_bytes * h];	png_byte **row = new png_byte*[h];	for(int i = 0; i < (int)h; i++) row[i] = img + row_bytes * i;	png_read_image(png_ptr,row);	png_read_end(png_ptr,NULL);	png_destroy_read_struct(&png_ptr,0,0);	delete row;	width = w;	height = h;	unsigned char *data = new unsigned char[width * height * 4];	unsigned char *ptr = data;	for(int i = 0; i < height; i++) {		for(int j = 0; j < width; j++) {			int k = row_bytes * i + j * channels;			*ptr++ = img[k + 0];			*ptr++ = img[k + 1];			*ptr++ = img[k + 2];			if(channels == 4) *ptr++ = img[k + 3];			else *ptr++ = 255;		}	}	delete img;	return data;}

xqhrs232 2011-04-16

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我的png_read_info( )函数怎么读不到PNG的INFO数据结构呢？？？

xqhrs232 2011-04-15

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LIBPNG类库自带有手册libpng-manual.txt和README文档，得仔细看看！！！

xqhrs232 2011-04-15

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有人成功移植opencv2.0到arm上的吗？

http://www.opencv.org.cn/forum/viewtopic.php?f=1&t=10421

xqhrs232 2011-04-15

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[Quote=引用 13 楼 oexpress 的回复:]
引用 10 楼 qthsrs232 的回复:

编译是已经成功了，产生了.a/.so库文件，但连接的时候怎么老报错啊！！！

C/C++ code

$ $NDK/ndk-build

undefined reference to `png_set_longjmp_fn'

/cygdrive/e/DirectX/Android_NDK_JNI/android-ndk-……
[/Quote]

看来的多看看pngconf.h文件了---------针对不同的平台得进行对应的配置！！！
LIBPNG类库移植还有个手册------libpng-1.4.0-manual.pdf----要多去读读

CyberLogix 2011-04-15

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[Quote=引用 10 楼 qthsrs232 的回复:]

编译是已经成功了，产生了.a/.so库文件，但连接的时候怎么老报错啊！！！

C/C++ code

$ $NDK/ndk-build

undefined reference to `png_set_longjmp_fn'

/cygdrive/e/DirectX/Android_NDK_JNI/android-ndk-r4b-windows/android-ndk-r4b/buil……
[/Quote]

说明你没有俩解C库阿，找不到stderr，longjmp等符号

xqhrs232 2011-04-15

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load png from asserts in android NDK

http://www.meegozu.com/forum-viewthread-tid-994-extra-%26page%3D1.html



Previously, I first extra my texture files to /data and then load them from native c++ code. But it's not a good way cause that is a waste to user's space. We can load file directly from APK file.

APK is some like a ZIP file. So we need libzip to help us reading resources from the APK file.

Luckily, I found someone from anddev had packed libzip and libpng for android NDK,  you can download it from here.

We need to add libpng and libzip to Application.mk:

APP_ABI := armeabi armeabi-v7a

APP_PROJECT_PATH := $(call my-dir)/project

APP_MODULES      := libpng libzip YOU_PROJECT_NAME

Add these to Android.mk

LOCAL_LDLIBS+=-L$(SYSROOT)/usr/lib -ldl

LOCAL_LDLIBS+=-L$(SYSROOT)/usr/lib -lz

Here is a snippet for loading apk file, if it works, it will list all files contained in the apk.



    static void loadAPK (const char* apkPath) {



    LOGI("Loading APK %s", apkPath);



    APKArchive = zip_open(apkPath, 0, NULL);



    if (APKArchive == NULL) {



        LOGE("Error loading APK");



    return;



  }







    //Just for debug, print APK contents



    int numFiles = zip_get_num_files(APKArchive);



    for (int i=0; i<numFiles; i++) {



        const char* name = zip_get_name(APKArchive, i, 0);



        if (name == NULL) {



        LOGE("Error reading zip file name at index %i : %s", zip_strerror(APKArchive));



        return;



    }



    LOGI("File %i : %s\n", i, name);



  }



}

复制代码





There is something to say about apkPath, it is where your apk is. You can generate it in Java and pass it to native code.



String apkFilePath = null;



ApplicationInfo appInfo = null;



PackageManager packMgmr = this.getPackageManager();



try {



        appInfo = packMgmr.getApplicationInfo("com.yourpackage", 0);



    } catch (NameNotFoundException e) {



        e.printStackTrace();



        throw new RuntimeException("Unable to locate assets, aborting...");



    }



apkFilePath = appInfo.sourceDir;



jni.init(apkFilePath);//pass it to NDK

复制代码



Now it's time to load PNGs!



int TexMng::LoadPNG(char* filename,bool _alpha)



{



    LOGI("Loading %s",filename);







    for(int i=0;i<nTex;++i)



    {



        if(strcmp(tex_name[i],filename)==0)



        {



            LOGI("Already Loaded");



            return -1;



        }







    }







    if(nTex>=MAX_TEXS)



    {



        LOGI("Too many textures!");



        return -1;



    }







  file = zip_fopen(APKArchive, filename, 0);



  if (!file) {



    LOGE("Error opening %s from APK", filename);



    return TEXTURE_LOAD_ERROR;



  }







  //header for testing if it is a png



  png_byte header[8];







  //read the header



  zip_fread(file, header, 8);







  //test if png



  int is_png = !png_sig_cmp(header, 0, 8);



  if (!is_png) {



    zip_fclose(file);



    LOGE("Not a png file : %s", filename);



    return TEXTURE_LOAD_ERROR;



  }







  //create png struct



  png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL,



      NULL, NULL);



  if (!png_ptr) {



    zip_fclose(file);



    LOGE("Unable to create png struct : %s", filename);



    return (TEXTURE_LOAD_ERROR);



  }







  //create png info struct



  png_infop info_ptr = png_create_info_struct(png_ptr);



  if (!info_ptr) {



    png_destroy_read_struct(&png_ptr, (png_infopp) NULL, (png_infopp) NULL);



    LOGE("Unable to create png info : %s", filename);



    zip_fclose(file);



    return (TEXTURE_LOAD_ERROR);



  }







  //create png info struct



  png_infop end_info = png_create_info_struct(png_ptr);



  if (!end_info) {



    png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp) NULL);



    LOGE("Unable to create png end info : %s", filename);



    zip_fclose(file);



    return (TEXTURE_LOAD_ERROR);



  }







  //png error stuff, not sure libpng man suggests this.



  if (setjmp(png_jmpbuf(png_ptr))) {



    zip_fclose(file);



    LOGE("Error during setjmp : %s", filename);



    png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);



    return (TEXTURE_LOAD_ERROR);



  }







  //init png reading



  //png_init_io(png_ptr, fp);



  png_set_read_fn(png_ptr, NULL, png_zip_read);







  //let libpng know you already read the first 8 bytes



  png_set_sig_bytes(png_ptr, 8);







  // read all the info up to the image data



  png_read_info(png_ptr, info_ptr);







  //variables to pass to get info



  int bit_depth, color_type;



  png_uint_32 twidth, theight;







  // get info about png



  png_get_IHDR(png_ptr, info_ptr, &twidth, &theight, &bit_depth, &color_type,



      NULL, NULL, NULL);







  //update width and height based on png info



  tex_w[nTex] = twidth;



  tex_h[nTex] = theight;







  // Update the png info struct.



  png_read_update_info(png_ptr, info_ptr);







  // Row size in bytes.



  int rowbytes = png_get_rowbytes(png_ptr, info_ptr);







  // Allocate the image_data as a big block, to be given to opengl



  png_byte *image_data = new png_byte[rowbytes * theight];



  if (!image_data) {



    //clean up memory and close stuff



    png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);



    LOGE("Unable to allocate image_data while loading %s ", filename);



    zip_fclose(file);



    return TEXTURE_LOAD_ERROR;



  }







  //row_pointers is for pointing to image_data for reading the png with libpng



  png_bytep *row_pointers = new png_bytep[theight];



  if (!row_pointers) {



    //clean up memory and close stuff



    png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);



    delete[] image_data;



    LOGE("Unable to allocate row_pointer while loading %s ", filename);



    zip_fclose(file);



    return TEXTURE_LOAD_ERROR;



  }



  // set the individual row_pointers to point at the correct offsets of image_data



  for (int i = 0; i < theight; ++i)



    row_pointers[theight - 1 - i] = image_data + i * rowbytes;







  //read the png into image_data through row_pointers



  png_read_image(png_ptr, row_pointers);







  alpha[nTex]=_alpha;



  pixels[nTex]=image_data;



  strcpy(tex_name[nTex],filename);



  ++nTex;



  png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);



  //delete[] image_data;



  delete[] row_pointers;



  zip_fclose(file);







  return nTex;



}

复制代码









本文转自：http://androgeek.info/?p=275

qthsrs232 2011-04-14

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编译是已经成功了，产生了.a/.so库文件，但连接的时候怎么老报错啊！！！





$ $NDK/ndk-build





undefined reference to `png_set_longjmp_fn'



/cygdrive/e/DirectX/Android_NDK_JNI/android-ndk-r4b-windows/android-ndk-r4b/build/platforms/android-8/arch-arm/usr/lib/libpng.so

(pngerror.o): In function `png_warning':

pngerror.c:(.text+0x230): undefined reference to `stderr'



(pngerror.o): In function `png_error':

pngerror.c:(.text+0x42c): undefined reference to `stderr'





(pngrutil.o): In function `png_handle_sRGB':

pngrutil.c:(.text+0x32c0): undefined reference to `stderr'







(pngrutil.o): In function `png_handle_cHRM':

pngrutil.c:(.text+0x38cc): undefined reference to `stderr'





(pngrutil.o): In function `png_handle_gAMA':

pngrutil.c:(.text+0x3c14): undefined reference to `stderr'

collect2: ld returned 1 exit status

不知道为什么，因为我的NDK版本过低？？？

xqhrs232 2011-04-14

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其实android2.2系统里面已经自带了libpng++++zlib类库的源代码了，但libpng没有自动编译！zlib类库编译为libz.so

libpng---version::1.2.44
zlib----version::1.2.3

xqhrs232 2011-04-14

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NDK 下面编译 libpng.已经如何在opengl es 里面读取png图片
http://blog.csdn.net/untosil/archive/2010/07/16/5739002.aspx



手上有好些,前一阶段的工作成果.一直没有时间整理出来.

先把cola2d 里面使用的一些基础整理下.



在ndk 下如何读取png到opengl es 的texture了?

其实做法和linux下面没什么区别,我们首先要用到libpng这个开源的库.

从 http://www.libpng.org/pub/png/libpng.html 下载到 libpng-1.2.41这个版本.



然后在android ndk 新建一个libpng的project .

我的android.mk 文件如下.



LOCAL_PATH := $(call my-dir)   

include $(CLEAR_VARS)   

LOCAL_MODULE := png  

LOCAL_CFLAGS := -I$(LOCAL_PATH)  \   

    -DPNG_USE_GLOBAL_ARRAYS \   

    -DPNG_READ_SUPPORTED   

  

LOCAL_CPP_EXTENSION := .cpp   

  

# Note this simple makefile var substitution, you can find even simpler examples in different Android projects   

LOCAL_SRC_FILES :=  $(notdir $(wildcard $(LOCAL_PATH)/*.c))   

include $(BUILD_STATIC_LIBRARY)  



LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

LOCAL_MODULE := png

LOCAL_CFLAGS := -I$(LOCAL_PATH)  \

	-DPNG_USE_GLOBAL_ARRAYS	\

	-DPNG_READ_SUPPORTED



LOCAL_CPP_EXTENSION := .cpp



# Note this simple makefile var substitution, you can find even simpler examples in different Android projects

LOCAL_SRC_FILES :=  $(notdir $(wildcard $(LOCAL_PATH)/*.c))

include $(BUILD_STATIC_LIBRARY)

这样就可以编译好libpng.a



需要注意的是 如果使用该库,链接时,需要加上-lz 这儿需要带上zlib库 这个库,android ndk 已经自带了.不需要自行编译.



opengl es 如何使用该库读取一个png图片了?

读取png 代码:



unsigned char* Texture::ReadPNG (const char* file, png_uint_32* w, png_uint_32* h)   

{   

    FILE* f;   

    unsigned char sig[8];   

    png_structp png_ptr;   

    png_infop   info_ptr;   

    unsigned char* image_data;   

    int bit_depth;   

    int color_type;   

    unsigned int rowbytes;   

    png_uint_32 i;   

    png_bytepp row_pointers;   

  

    if ((f = fopen(file, "rb")) == NULL)   

        return NULL;   

    fread(sig, sizeof(*sig), sizeof(sig), f);   

    if (!png_check_sig(sig, sizeof(*sig))) {   

        fclose(f);   

        return NULL;   

    }   

    if ((png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)) == NULL) {   

        fclose(f);   

        return NULL;   

    }   

    if ((info_ptr = png_create_info_struct(png_ptr)) == NULL) {   

        png_destroy_read_struct(&png_ptr, NULL, NULL);   

        fclose(f);   

        return NULL;   

    }   

  

    if (setjmp(png_jmpbuf(png_ptr))) {   

        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);   

        fclose(f);   

        return NULL;   

    }   

    png_ptr->io_ptr = (png_voidp) f;   

    png_set_sig_bytes(png_ptr, 8);   

  

    png_read_info(png_ptr, info_ptr);   

    png_get_IHDR(png_ptr, info_ptr, w, h, &bit_depth, &color_type, NULL, NULL, NULL);   

    if (color_type & PNG_COLOR_MASK_ALPHA)   

        png_set_strip_alpha(png_ptr);   

    if (bit_depth > <IMG class=wp-smiley alt=8) src="http://www.adevgames.com/wordpress/wp-includes/images/smilies/icon_cool.gif">  

        png_set_strip_16(png_ptr);   

    if (color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_GRAY_ALPHA)   

        png_set_gray_to_rgb(png_ptr);   

    if (color_type == PNG_COLOR_TYPE_PALETTE)   

        png_set_palette_to_rgb(png_ptr);   

    png_read_update_info(png_ptr, info_ptr);   

  

    rowbytes = png_get_rowbytes(png_ptr, info_ptr);   

    if ((image_data =(unsigned char *) malloc(*h * rowbytes)) == NULL) {   

        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);   

        fclose(f);   

        return NULL;   

    }   

    if ((row_pointers =(png_bytepp) malloc(*h * sizeof(png_bytep))) == NULL) {   

        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);   

        fclose(f);   

        free(image_data);   

        return NULL;   

    }   

  

    for (i = 0; i < *h; i++)   

        row_pointers[*h - 1 - i] = image_data + i*rowbytes;   

    png_read_image(png_ptr, row_pointers);   

    free(row_pointers);   

    png_destroy_read_struct(&png_ptr, &info_ptr, NULL);   

    fclose(f);   

  

    return image_data;   

}  



unsigned char* Texture::ReadPNG (const char* file, png_uint_32* w, png_uint_32* h)

{

	FILE* f;

	unsigned char sig[8];

	png_structp png_ptr;

	png_infop   info_ptr;

	unsigned char* image_data;

	int bit_depth;

	int color_type;

	unsigned int rowbytes;

	png_uint_32 i;

	png_bytepp row_pointers;



	if ((f = fopen(file, "rb")) == NULL)

		return NULL;

	fread(sig, sizeof(*sig), sizeof(sig), f);

	if (!png_check_sig(sig, sizeof(*sig))) {

		fclose(f);

		return NULL;

	}

	if ((png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)) == NULL) {

		fclose(f);

		return NULL;

	}

	if ((info_ptr = png_create_info_struct(png_ptr)) == NULL) {

		png_destroy_read_struct(&png_ptr, NULL, NULL);

		fclose(f);

		return NULL;

	}



	if (setjmp(png_jmpbuf(png_ptr))) {

		png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

		fclose(f);

		return NULL;

	}

	png_ptr->io_ptr = (png_voidp) f;

	png_set_sig_bytes(png_ptr, 8);



	png_read_info(png_ptr, info_ptr);

	png_get_IHDR(png_ptr, info_ptr, w, h, &bit_depth, &color_type, NULL, NULL, NULL);

	if (color_type & PNG_COLOR_MASK_ALPHA)

		png_set_strip_alpha(png_ptr);

	if (bit_depth > 

		png_set_strip_16(png_ptr);

	if (color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_GRAY_ALPHA)

		png_set_gray_to_rgb(png_ptr);

	if (color_type == PNG_COLOR_TYPE_PALETTE)

		png_set_palette_to_rgb(png_ptr);

	png_read_update_info(png_ptr, info_ptr);



	rowbytes = png_get_rowbytes(png_ptr, info_ptr);

	if ((image_data =(unsigned char *) malloc(*h * rowbytes)) == NULL) {

		png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

		fclose(f);

		return NULL;

	}

	if ((row_pointers =(png_bytepp) malloc(*h * sizeof(png_bytep))) == NULL) {

		png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

		fclose(f);

		free(image_data);

		return NULL;

	}



	for (i = 0; i < *h; i++)

		row_pointers[*h - 1 - i] = image_data + i*rowbytes;

	png_read_image(png_ptr, row_pointers);

	free(row_pointers);

	png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

	fclose(f);



	return image_data;

}然后使用

下面方法即可读入到texture里面



m_width=imgw;   

    m_height=imgh;   

      glGenTextures(1, &m_id);   

        glBindTexture(GL_TEXTURE_2D, m_id);   

        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, imgw, imgh, 0, GL_RGBA, GL_UNSIGNED_BYTE, image);   

        GLint crop[4] = { 0, 0, m_width, m_height };   

    glTexParameteriv(GL_TEXTURE_2D, GL_TEXTURE_CROP_RECT_OES, crop);   

    glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);   

    glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);   

    //glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);   

    glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );  



m_width=imgw;

  	m_height=imgh;

	  glGenTextures(1, &m_id);

		glBindTexture(GL_TEXTURE_2D, m_id);

		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, imgw, imgh, 0, GL_RGBA, GL_UNSIGNED_BYTE, image);

		GLint crop[4] = { 0, 0, m_width, m_height };

    glTexParameteriv(GL_TEXTURE_2D, GL_TEXTURE_CROP_RECT_OES, crop);

    glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

    glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

    //glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);

    glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );

这部分内容和普通opengl es 的开发都没有区别.







本文来自CSDN博客，转载请标明出处：http://blog.csdn.net/untosil/archive/2010/07/16/5739002.aspx

xqhrs232 2011-04-14

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OpenGL ES

Android support for OpenGL ES, a subset of OpenGL, is exposed both in Java and native API. 2009FLY文摘,正正博客 WWW.2009FLY.COM 



All android devices supports version OpenGL ES version 1.0, though some may use a software renderer. Applications which requires (as opposed to may optionally use features from through runtime checks) a higher version must specify so in their AndroidManifest.xml file with the android:glEsVersion attribute on the <uses-feature/> tag, as a 32-bit number with the higher and lower 16 bits representing the major and minor OpenGL version number: 



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<-- require OpenGL ES version 1.0 (default) -->

<uses-feature android:glEsVersion="0x00010000"/>



<-- require OpenGL ES version 1.1 -->

<uses-feature android:glEsVersion="0x00010001"/>



<-- require OpenGL ES version 2.0 -->

<uses-feature android:glEsVersion="0x00020000"/> 

网络安全  2009FLY文摘,正正博客 WWW.2009FLY.COM Note that the Android emulator does not support OpenGL ES version 2.x - a physical device is required for testing applications using that version. 网络安全 2009FLY文摘,正正博客 WWW.2009FLY.COM