{"id":3884,"date":"2018-03-21T21:47:49","date_gmt":"2018-03-21T13:47:49","guid":{"rendered":"http:\/\/www.bookcard.net\/wordpress\/?p=3884"},"modified":"2018-10-14T21:21:50","modified_gmt":"2018-10-14T13:21:50","slug":"opengl_multitexture","status":"publish","type":"post","link":"https:\/\/www.bookcard.net\/wordpress\/opengl_multitexture\/","title":{"rendered":"OpenGL\u4e4b\u591a\u7d0b\u7406\u6620\u5c04"},"content":{"rendered":"
\"\"<\/a>
OpenGL\u4e4b\u591a\u7d0b\u7406\u6620\u5c04<\/figcaption><\/figure>\n

OpenGL\u53ef\u540c\u6642\u5c0d\u591a\u908a\u5f62\u6620\u5c04\u591a\u500b\u7d0b\u7406,\u7a31\u70ba\u300e\u591a\u7d0b\u7406\u6620\u5c04\u300f. \u5b83\u662fOpenGL\u7684\u53ef\u9078\u64f4\u5c55\u5be6\u73fe,\u4e26\u975e\u6240\u6709\u7684OpenGL\u90fd\u6709\u5be6\u73fe.\u300eOpenGL API\u7684\u6240\u6709\u64f4\u5c55\u5fc5\u9808\u5f97\u5230ARB(OpenGL\u9ad4\u7cfb\u8a55\u5be9\u59d4\u54e1\u6703)\u7684\u8a8d\u53ef\u300f,\u5728\u9032\u884c\u591a\u7d0b\u7406\u6620\u5c04\u6642,\u6bcf\u500b\u7d0b\u7406\u55ae\u5143\u90fd\u5c07\u6620\u5c04\u7d50\u679c\u50b3\u905e\u7d66\u4e0b\u500b\u7d0b\u7406\u55ae\u5143,\u76f4\u81f3\u6240\u6709\u7684\u7d0b\u7406\u7684\u7d0b\u7406\u55ae\u5143\u90fd\u9032\u884c\u6620\u5c04(\u6700\u7d42\u7d50\u679c)\u6f14\u793a\u7a0b\u5f0f:\u4e0b\u8f7d<\/a><\/p>\n\n\n\n\n\n\n\n
\u591a\u7d0b\u7406\u6620\u5c04\u5206\u70ba\u56db\u500b\u6b65\u9a5f:<\/td>\n<\/tr>\n
1.\u5224\u65b7\u662f\u5426\u652f\u6301\u300e\u591a\u7d0b\u7406\u6620\u5c04\u300f<\/td>\n<\/tr>\n
2.\u8b80\u53d6\u64f4\u5c55\u51fd\u5f0f\u7684\u6307\u91dd<\/td>\n<\/tr>\n
3.\u5efa\u7acb\u7d0b\u7406\u55ae\u5143<\/td>\n<\/tr>\n
4.\u8a2d\u7f6e\u7d0b\u7406\u5750\u6a19<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u5b9a\u7fa9\u591a\u7d0b\u7406\u6620\u5c04\u7d50\u69cb<\/p>\n

typedef struct MULTITEXTURE_TYP {<\/p>\n

TEXTURE<\/a> texture0;<\/p>\n

TEXTURE<\/a> texture1;<\/p>\n

}MULTITEXTURE,*MULTITEXTURE_PTR;<\/p>\n

1.\u9a57\u8b49\u7576\u524d\u7248\u672c\u7684OpenGL\u662f\u5426\u652f\u6301\u300e\u591a\u7d0b\u7406\u6620\u5c04\u300f<\/p>\n\n\n\n\n\n
\u51fd\u5f0f<\/td>\n\u7c21\u4ecb<\/td>\n<\/tr>\n
glGetString(GL_EXTENSIONS)<\/a><\/td>\n\u7372\u53d6OpenGL\u6240\u652f\u6301\u7684\u6240\u6709\u64f4\u5c55\u51fd\u5f0f<\/p>\n

\u8fd4\u56de\u4ee5\u7a7a\u683c\u9694\u958b\u7684\u5b57\u7b26\u4e32\u5217\u8868<\/td>\n<\/tr>\n

GL_ARB_multitexture<\/td>\n\u67e5\u627e\uff08GL_ARB_multitexture\uff09\u5224\u65b7\u662f\u5426\u652f\u6301\u300e\u591a\u7d0b\u7406\u6620\u5c04\u300f<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u5224\u65b7\u662f\u5426\u652f\u6301\u67d0\u4e00\u64f4\u5c55\u51fd\u5f0f<\/p>\n

bool Extensions_OpenGL(const char * name)<\/p>\n

{<\/p>\n

char * extensions;<\/p>\n

int index = 0;<\/p>\n

int length,n;<\/p>\n

extensions = (char*)glGetString(GL_EXTENSIONS);<\/a>\/\/ \u64f4\u5c55\u51fd\u5f0f<\/p>\n

length = strlen(name);\/\/ \u9577\u5ea6<\/p>\n

while (extensions[index] != NULL)\/\/ \u5faa\u74b0\u67e5\u627e<\/p>\n

{<\/p>\n

n = strcspn(extensions + index, ” “);\/\/ \u67e5\u627e\u7a7a\u683c<\/p>\n

if (n == length && strncmp(extensions + index, name, length) == 0)\/\/ \u6bd4\u8f03<\/p>\n

return true;<\/p>\n

index = index + n + 1; \/\/ \u8df3\u904e\u7a7a\u683c<\/p>\n

}<\/p>\n

return false;<\/p>\n

}<\/p>\n

2.\u8b80\u53d6\u64f4\u5c55\u51fd\u5f0f\u7684\u6307\u91dd<\/p>\n\n\n\n\n
\u51fd\u5f0f<\/td>\n\u7c21\u4ecb<\/td>\n<\/tr>\n
PROC wglGetProcAddress(LPCSTR lpszProc);<\/td>\n\u8fd4\u56de\u64f4\u5c55\u51fd\u5f0f\u7684\u5730\u5740<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n\n\n\n\n\n\n
\u64f4\u5c55\u51fd\u5f0f\u5b9a\u7fa9<\/td>\n\u7c21\u4ecb<\/td>\n<\/tr>\n
typedef void (APIENTRY * PFNGLMULTITEXCOORD2FARBPROC) (GLenum target, GLfloat s, GLfloat t);<\/td>\n\u70ba\u591a\u7d0b\u7406\u6620\u5c04\u8a2d\u7f6e\u7d0b\u7406\u5ea7\u6a19<\/td>\n<\/tr>\n
typedef void (APIENTRY * PFNGLACTIVETEXTUREARBPROC) (GLenum texture);<\/td>\n\u8a2d\u7f6e\u7576\u524d\u7684\u7d0b\u7406\u55ae\u5143<\/td>\n<\/tr>\n
typedef void (APIENTRY * PFNGLCLIENTACTIVETEXTUREARBPROC) (GLenum texture);<\/td>\n\u8a2d\u7f6e\u9078\u64c7\u7576\u524d\u7684\u7d0b\u7406\u55ae\u4f4d,\u4ee5\u4fbf\u7528\u9802\u9ede\u6578\u7d44\u6307\u5b9a\u7d0b\u7406\u5750\u6a19\u6578\u64da<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u521d\u6b64\u5316\u591a\u7d0b\u7406\u6620\u5c04<\/p>\n

PFNGLMULTITEXCOORD2FARBPROC\u00a0\u00a0\u00a0\u00a0 glMultiTexCoord2fARB;<\/p>\n

PFNGLACTIVETEXTUREARBPROC\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 glActiveTextureARB;<\/p>\n

PFNGLCLIENTACTIVETEXTUREARBPROC glClientActiveTextureARB;<\/p>\n

void Init_Multitexture()<\/p>\n

{\/\/ \u5224\u65b7\u662f\u5426\u652f\u6301\u67d0\u4e00\u64f4\u5c55\u51fd\u5f0f<\/p>\n

if( Extensions_OpenGL(“GL_ARB_multitexture”) )<\/p>\n

{<\/p>\n

glMultiTexCoord2fARB=(PFNGLMULTITEXCOORD2FARBPROC)wglGetProcAddress(“glMultiTexCoord2fARB”);<\/p>\n

glActiveTextureARB=(PFNGLACTIVETEXTUREARBPROC)wglGetProcAddress(“glActiveTextureARB”);<\/p>\n

glClientActiveTextureARB=(PFNGLCLIENTACTIVETEXTUREARBPROC)wglGetProcAddress(“glClientActiveTextureARB”);<\/p>\n

}<\/p>\n

}<\/p>\n

3.\u5efa\u7acb\u7d0b\u7406\u55ae\u5143<\/p>\n\n\n\n\n\n
\u8f09\u5165\u7d0b\u7406\u4e26\u7d81\u5b9a<\/td>\n\u7c21\u4ecb<\/td>\n<\/tr>\n
\u300e.bmp\u300f<\/a> \u300e.tga\u300f<\/a> \u300e.pcx\u300f<\/a><\/td>\n\u8f09\u5165\u7d0b\u7406\u6587\u4ef6<\/td>\n<\/tr>\n
glGenTextures(1, &texture->ID);<\/a><\/p>\n

glBindTexture(GL_TEXTURE_2D, texture->ID);<\/a><\/td>\n

\u751f\u6210\u7d0b\u7406\u55ae\u5143\u7d81\u5b9a\u7d0b\u7406<\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u6fc0\u6d3b\u591a\u7d0b\u7406\u6620\u5c04<\/p>\n

void Active_Multitexture(MULTITEXTURE_PTR multitexture)<\/p>\n

{<\/p>\n

glActiveTextureARB(GL_TEXTURE0_ARB);<\/p>\n

glEnable(GL_TEXTURE_2D);<\/p>\n

glBindTexture(GL_TEXTURE_2D, multitexture->texture0.ID);\/\/ \u7d81\u5b9a\u7d0b\u7406<\/p>\n

glActiveTextureARB(GL_TEXTURE1_ARB);<\/p>\n

glEnable(GL_TEXTURE_2D);<\/p>\n

glBindTexture(GL_TEXTURE_2D, multitexture->texture1.ID);\/\/ \u7d81\u5b9a\u7d0b\u7406<\/p>\n

}<\/p>\n

OpenGL\u6700\u591a\u652f\u630132\u500b\u7d0b\u7406\u300eGL_TEXTURE0_ARB\u300f~\u300eGL_TEXTURE31_ARB\u300f<\/p>\n

\u4f46\u6700\u5f8c\u901a\u904e\u67e5\u8a62\u7576\u524d\u7248\u672c\u652f\u6301\u7684\u6700\u5927\u55ae\u5143\u91cf<\/p>\n

int maxTexUnits;<\/p>\n

glGetIntegerv(GL_MAX_TEXTURE_UNITS_ARB,&maxTexUnits);<\/p>\n

 <\/p>\n

4.\u8a2d\u7f6e\u7d0b\u7406\u5750\u6a19<\/p>\n\n\n\n\n\n\n
 <\/td>\n\u7c21\u4ecb<\/td>\n<\/tr>\n
void glMultiTexCoord2fARB(GLenum texUnit,float coords);<\/td>\n\u8a2d\u7f6e\u7d0b\u7406\u5750\u6a19<\/td>\n<\/tr>\n
texUnit: GL_TEXTURE0_ARB~GL_TEXTURE31_ARB<\/td>\n\u7d0b\u7406\u55ae\u5143\u7d22\u5f15<\/td>\n<\/tr>\n
Coords:<\/td>\n\u7d0b\u7406\u5750\u6a19<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

OpenGL\u53ef\u540c\u6642\u5c0d\u591a\u908a\u5f62\u6620\u5c04\u591a\u500b\u7d0b\u7406,\u7a31\u70ba\u300e\u591a\u7d0b\u7406\u6620\u5c04\u300f. \u5b83\u662fOpenGL\u7684\u53ef\u9078\u64f4\u5c55\u5be6\u73fe,\u4e26\u975e\u6240\u6709\u7684Ope … <\/p>\n

\u7e7c\u7e8c\u95b1\u8b80 OpenGL\u4e4b\u591a\u7d0b\u7406\u6620\u5c04<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[62],"tags":[50],"class_list":["post-3884","post","type-post","status-publish","format-standard","hentry","category-opengl","tag-opengl","entry"],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.bookcard.net\/wordpress\/wp-json\/wp\/v2\/posts\/3884","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bookcard.net\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bookcard.net\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bookcard.net\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bookcard.net\/wordpress\/wp-json\/wp\/v2\/comments?post=3884"}],"version-history":[{"count":3,"href":"https:\/\/www.bookcard.net\/wordpress\/wp-json\/wp\/v2\/posts\/3884\/revisions"}],"predecessor-version":[{"id":3890,"href":"https:\/\/www.bookcard.net\/wordpress\/wp-json\/wp\/v2\/posts\/3884\/revisions\/3890"}],"wp:attachment":[{"href":"https:\/\/www.bookcard.net\/wordpress\/wp-json\/wp\/v2\/media?parent=3884"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bookcard.net\/wordpress\/wp-json\/wp\/v2\/categories?post=3884"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bookcard.net\/wordpress\/wp-json\/wp\/v2\/tags?post=3884"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}