{"id":2353,"date":"2020-09-12T15:04:58","date_gmt":"2020-09-12T07:04:58","guid":{"rendered":"http:\/\/blog.coolcoding.cn\/?p=2353"},"modified":"2020-09-12T19:03:59","modified_gmt":"2020-09-12T11:03:59","slug":"%e9%ab%98%e7%ba%a7glsl","status":"publish","type":"post","link":"https:\/\/blog.coolcoding.cn\/?p=2353","title":{"rendered":"[\u8f6c]\u5b66\u4e60OpenGL-ES\uff1a\u9ad8\u7ea7GLSL"},"content":{"rendered":"\n

\u539f\u6587\uff1ahttps:\/\/learnopengl-cn.github.io\/04%20Advanced%20OpenGL\/08%20Advanced%20GLSL\/<\/a><\/p>\n\n\n\n

<\/p>\n\n\n\n

\u8fd9\u4e00\u5c0f\u8282\u5e76\u4e0d\u4f1a\u5411\u4f60\u5c55\u793a\u975e\u5e38\u5148\u8fdb\u975e\u5e38\u9177\u7684\u65b0\u7279\u6027\uff0c\u4e5f\u4e0d\u4f1a\u5bf9\u573a\u666f\u7684\u89c6\u89c9\u8d28\u91cf\u6709\u663e\u8457\u7684\u63d0\u9ad8\u3002\u4f46\u662f\uff0c\u8fd9\u4e00\u8282\u4f1a\u6216\u591a\u6216\u5c11\u6d89\u53caGLSL\u7684\u4e00\u4e9b\u6709\u8da3\u7684\u5730\u65b9\u4ee5\u53ca\u4e00\u4e9b\u5f88\u68d2\u7684\u6280\u5de7\uff0c\u5b83\u4eec\u53ef\u80fd\u5728\u4eca\u540e\u4f1a\u5e2e\u52a9\u5230\u4f60\u3002\u7b80\u5355\u6765\u8bf4\uff0c\u5b83\u4eec\u5c31\u662f\u5728\u7ec4\u5408\u4f7f\u7528OpenGL\u548cGLSL\u521b\u5efa\u7a0b\u5e8f\u65f6\u7684\u4e00\u4e9b\u6700\u597d\u8981\u77e5\u9053\u7684\u4e1c\u897f<\/strong>\uff0c\u548c\u4e00\u4e9b\u4f1a\u8ba9\u4f60\u751f\u6d3b\u66f4\u52a0\u8f7b\u677e\u7684\u7279\u6027<\/strong>\u3002<\/p>\n\n\n\n

\u6211\u4eec\u5c06\u4f1a\u8ba8\u8bba\u4e00\u4e9b\u6709\u8da3\u7684\u5185\u5efa\u53d8\u91cf(Built-in Variable)\uff0c\u7ba1\u7406\u7740\u8272\u5668\u8f93\u5165\u548c\u8f93\u51fa\u7684\u65b0\u65b9\u5f0f\u4ee5\u53ca\u4e00\u4e2a\u53eb\u505aUniform\u7f13\u51b2\u5bf9\u8c61(Uniform Buffer Object)\u7684\u6709\u7528\u5de5\u5177\u3002<\/p>\n\n\n\n

GLSL\u7684\u5185\u5efa\u53d8\u91cf<\/h1>\n\n\n\n

\u7740\u8272\u5668\u90fd\u662f\u6700\u7b80\u5316\u7684\uff0c\u5982\u679c\u9700\u8981\u5f53\u524d\u7740\u8272\u5668\u4ee5\u5916\u5730\u65b9\u7684\u6570\u636e\u7684\u8bdd\uff0c\u6211\u4eec\u5fc5\u987b\u8981\u5c06\u6570\u636e\u4f20\u8fdb\u6765\u3002\u6211\u4eec\u5df2\u7ecf\u5b66\u4f1a\u4f7f\u7528\u9876\u70b9\u5c5e\u6027\u3001uniform\u548c\u91c7\u6837\u5668\u6765\u5b8c\u6210\u8fd9\u4e00\u4efb\u52a1\u4e86\u3002\u7136\u800c\uff0c\u9664\u6b64\u4e4b\u5916\uff0cGLSL\u8fd8\u5b9a\u4e49\u4e86\u53e6\u5916\u51e0\u4e2a\u4ee5gl_<\/code>\u4e3a\u524d\u7f00\u7684\u53d8\u91cf\uff0c\u5b83\u4eec\u80fd\u63d0\u4f9b\u7ed9\u6211\u4eec\u66f4\u591a\u7684\u65b9\u5f0f\u6765\u8bfb\u53d6\/\u5199\u5165\u6570\u636e\u3002\u6211\u4eec\u5df2\u7ecf\u5728\u524d\u9762\u6559\u7a0b\u4e2d\u63a5\u89e6\u8fc7\u5176\u4e2d\u7684\u4e24\u4e2a\u4e86\uff1a\u9876\u70b9\u7740\u8272\u5668\u7684\u8f93\u51fa\u5411\u91cfgl_Position\uff0c\u548c\u7247\u6bb5\u7740\u8272\u5668\u7684gl_FragCoord\u3002<\/p>\n\n\n\n

\u6211\u4eec\u5c06\u4f1a\u8ba8\u8bba\u51e0\u4e2a\u6709\u8da3\u7684GLSL\u5185\u5efa\u8f93\u5165\u548c\u8f93\u51fa\u53d8\u91cf\uff0c\u5e76\u4f1a\u89e3\u91ca\u5b83\u4eec\u80fd\u591f\u600e\u6837\u5e2e\u52a9\u4f60\u3002\u6ce8\u610f\uff0c\u6211\u4eec\u5c06\u4e0d\u4f1a\u8ba8\u8bbaGLSL\u4e2d\u5b58\u5728\u7684\u6240\u6709\u5185\u5efa\u53d8\u91cf\uff0c\u5982\u679c\u4f60\u60f3\u77e5\u9053\u6240\u6709\u7684\u5185\u5efa\u53d8\u91cf\u7684\u8bdd\uff0c\u8bf7\u67e5\u770bOpenGL\u7684wiki<\/a>\u3002<\/p>\n\n\n\n

\u9876\u70b9\u7740\u8272\u5668\u53d8\u91cf<\/h2>\n\n\n\n

\u6211\u4eec\u5df2\u7ecf\u89c1\u8fc7gl_Position\u4e86\uff0c\u5b83\u662f\u9876\u70b9\u7740\u8272\u5668\u7684\u88c1\u526a\u7a7a\u95f4\u8f93\u51fa\u4f4d\u7f6e\u5411\u91cf\u3002\u5982\u679c\u4f60\u60f3\u5728\u5c4f\u5e55\u4e0a\u663e\u793a\u4efb\u4f55\u4e1c\u897f\uff0c\u5728\u9876\u70b9\u7740\u8272\u5668\u4e2d\u8bbe\u7f6egl_Position\u662f\u5fc5\u987b\u7684\u6b65\u9aa4\u3002\u8fd9\u5df2\u7ecf\u662f\u5b83\u7684\u5168\u90e8\u529f\u80fd\u4e86\u3002<\/p>\n\n\n\n

gl_PointSize<\/h3>\n\n\n\n

\u6211\u4eec\u80fd\u591f\u9009\u7528\u7684\u5176\u4e2d\u4e00\u4e2a\u56fe\u5143\u662fGL_POINTS\uff0c\u5982\u679c\u4f7f\u7528\u5b83\u7684\u8bdd\uff0c\u6bcf\u4e00\u4e2a\u9876\u70b9\u90fd\u662f\u4e00\u4e2a\u56fe\u5143\uff0c\u90fd\u4f1a\u88ab\u6e32\u67d3\u4e3a\u4e00\u4e2a\u70b9\u3002\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7OpenGL\u7684glPointSize\u51fd\u6570\u6765\u8bbe\u7f6e\u6e32\u67d3\u51fa\u6765\u7684\u70b9\u7684\u5927\u5c0f\uff0c\u4f46\u6211\u4eec\u4e5f\u53ef\u4ee5\u5728\u9876\u70b9\u7740\u8272\u5668\u4e2d\u4fee\u6539\u8fd9\u4e2a\u503c\u3002<\/p>\n\n\n\n

GLSL\u5b9a\u4e49\u4e86\u4e00\u4e2a\u53eb\u505agl_PointSize\u8f93\u51fa\u53d8\u91cf\uff0c\u5b83\u662f\u4e00\u4e2afloat\u53d8\u91cf\uff0c\u4f60\u53ef\u4ee5\u4f7f\u7528\u5b83\u6765\u8bbe\u7f6e\u70b9\u7684\u5bbd\u9ad8\uff08\u50cf\u7d20\uff09\u3002\u5728\u9876\u70b9\u7740\u8272\u5668\u4e2d\u4fee\u6539\u70b9\u7684\u5927\u5c0f\u7684\u8bdd\uff0c\u4f60\u5c31\u80fd\u5bf9\u6bcf\u4e2a\u9876\u70b9\u8bbe\u7f6e\u4e0d\u540c\u7684\u503c\u4e86\u3002<\/p>\n\n\n\n

\u5728\u9876\u70b9\u7740\u8272\u5668\u4e2d\u4fee\u6539\u70b9\u5927\u5c0f\u7684\u529f\u80fd\u9ed8\u8ba4\u662f\u7981\u7528\u7684\uff0c\u5982\u679c\u4f60\u9700\u8981\u542f\u7528\u5b83\u7684\u8bdd\uff0c\u4f60\u9700\u8981\u542f\u7528OpenGL\u7684GL_PROGRAM_POINT_SIZE\uff1a<\/p>\n\n\n\n

glEnable(GL_PROGRAM_POINT_SIZE);\n<\/code><\/pre>\n\n\n\n
\u4e00\u4e2a\u7b80\u5355\u7684\u4f8b\u5b50\u5c31\u662f\u5c06\u70b9\u7684\u5927\u5c0f\u8bbe\u7f6e\u4e3a\u88c1\u526a\u7a7a\u95f4\u4f4d\u7f6e\u7684z\u503c\uff0c\u4e5f\u5c31\u662f\u9876\u70b9\u8ddd\u89c2\u5bdf\u8005\u7684\u8ddd\u79bb\u3002\u70b9\u7684\u5927\u5c0f\u4f1a\u968f\u7740\u89c2\u5bdf\u8005\u8ddd\u9876\u70b9\u8ddd\u79bb\u53d8\u8fdc\u800c\u589e\u5927\u3002<\/p>\n\n\n\n
void main()\n{\n    gl_Position = projection * view * model * vec4(aPos, 1.0);    \n    gl_PointSize = gl_Position.z;    \n}\n<\/code><\/pre>\n\n\n\n
\u7ed3\u679c\u5c31\u662f\uff0c\u5f53\u6211\u4eec\u8fdc\u79bb\u8fd9\u4e9b\u70b9\u7684\u65f6\u5019\uff0c\u5b83\u4eec\u4f1a\u53d8\u5f97\u66f4\u5927\uff1a<\/p>\n\n\n\n
\"\"\/<\/figure>\n\n\n\n
\u4f60\u53ef\u4ee5\u60f3\u5230\uff0c\u5bf9\u6bcf\u4e2a\u9876\u70b9\u4f7f\u7528\u4e0d\u540c\u7684\u70b9\u5927\u5c0f\uff0c\u4f1a\u5728\u7c92\u5b50\u751f\u6210\u4e4b\u7c7b\u7684\u6280\u672f\u4e2d\u5f88\u6709\u610f\u601d\u3002<\/p>\n\n\n\n
gl_VertexID<\/h3>\n\n\n\n
gl_Position\u548cgl_PointSize\u90fd\u662f\u8f93\u51fa\u53d8\u91cf<\/strong>\uff0c\u56e0\u4e3a\u5b83\u4eec\u7684\u503c\u662f\u4f5c\u4e3a\u9876\u70b9\u7740\u8272\u5668\u7684\u8f93\u51fa\u88ab\u8bfb\u53d6\u7684\u3002\u6211\u4eec\u53ef\u4ee5\u5bf9\u5b83\u4eec\u8fdb\u884c\u5199\u5165\uff0c\u6765\u6539\u53d8\u7ed3\u679c\u3002\u9876\u70b9\u7740\u8272\u5668\u8fd8\u4e3a\u6211\u4eec\u63d0\u4f9b\u4e86\u4e00\u4e2a\u6709\u8da3\u7684\u8f93\u5165\u53d8\u91cf<\/strong>\uff0c\u6211\u4eec\u53ea\u80fd\u5bf9\u5b83\u8fdb\u884c\u8bfb\u53d6\uff0c\u5b83\u53eb\u505agl_VertexID\u3002<\/p>\n\n\n\n
\u6574\u578b\u53d8\u91cfgl_VertexID\u50a8\u5b58\u4e86\u6b63\u5728\u7ed8\u5236\u9876\u70b9\u7684\u5f53\u524dID\u3002\u5f53\uff08\u4f7f\u7528glDrawElements\uff09\u8fdb\u884c\u7d22\u5f15\u6e32\u67d3\u7684\u65f6\u5019\uff0c\u8fd9\u4e2a\u53d8\u91cf\u4f1a\u5b58\u50a8\u6b63\u5728\u7ed8\u5236\u9876\u70b9\u7684\u5f53\u524d\u7d22\u5f15\u3002\u5f53\uff08\u4f7f\u7528glDrawArrays\uff09\u4e0d\u4f7f\u7528\u7d22\u5f15\u8fdb\u884c\u7ed8\u5236\u7684\u65f6\u5019\uff0c\u8fd9\u4e2a\u53d8\u91cf\u4f1a\u50a8\u5b58\u4ece\u6e32\u67d3\u8c03\u7528\u5f00\u59cb\u7684\u5df2\u5904\u7406\u9876\u70b9\u6570\u91cf\u3002<\/p>\n\n\n\n
\u867d\u7136\u73b0\u5728\u5b83\u6ca1\u6709\u4ec0\u4e48\u5177\u4f53\u7684\u7528\u9014\uff0c\u4f46\u77e5\u9053\u6211\u4eec\u80fd\u591f\u8bbf\u95ee\u8fd9\u4e2a\u4fe1\u606f\u603b\u662f\u597d\u7684\u3002<\/p>\n\n\n\n
\u7247\u6bb5\u7740\u8272\u5668\u53d8\u91cf<\/h2>\n\n\n\n
\u5728\u7247\u6bb5\u7740\u8272\u5668\u4e2d\uff0c\u6211\u4eec\u4e5f\u80fd\u8bbf\u95ee\u5230\u4e00\u4e9b\u6709\u8da3\u7684\u53d8\u91cf\u3002GLSL\u63d0\u4f9b\u7ed9\u6211\u4eec\u4e24\u4e2a\u6709\u8da3\u7684\u8f93\u5165\u53d8\u91cf\uff1agl_FragCoord\u548cgl_FrontFacing\u3002<\/p>\n\n\n\n
gl_FragCoord<\/h3>\n\n\n\n
\u5728\u8ba8\u8bba\u6df1\u5ea6\u6d4b\u8bd5\u7684\u65f6\u5019\uff0c\u6211\u4eec\u5df2\u7ecf\u89c1\u8fc7gl_FragCoord\u5f88\u591a\u6b21\u4e86\uff0c\u56e0\u4e3agl_FragCoord\u7684z\u5206\u91cf\u7b49\u4e8e\u5bf9\u5e94\u7247\u6bb5\u7684\u6df1\u5ea6\u503c\u3002\u7136\u800c\uff0c\u6211\u4eec\u4e5f\u80fd\u4f7f\u7528\u5b83\u7684x\u548cy\u5206\u91cf\u6765\u5b9e\u73b0\u4e00\u4e9b\u6709\u8da3\u7684\u6548\u679c\u3002<\/p>\n\n\n\n
gl_FragCoord\u7684x\u548cy\u5206\u91cf\u662f\u7247\u6bb5\u7684\u7a97\u53e3\u7a7a\u95f4(Window-space)\u5750\u6807\uff0c\u5176\u539f\u70b9\u4e3a\u7a97\u53e3\u7684\u5de6\u4e0b\u89d2\u3002\u6211\u4eec\u5df2\u7ecf\u4f7f\u7528glViewport\u8bbe\u5b9a\u4e86\u4e00\u4e2a800×600\u7684\u7a97\u53e3\u4e86\uff0c\u6240\u4ee5\u7247\u6bb5\u7a97\u53e3\u7a7a\u95f4\u5750\u6807\u7684x\u5206\u91cf\u5c06\u57280\u5230800\u4e4b\u95f4\uff0cy\u5206\u91cf\u57280\u5230600\u4e4b\u95f4\u3002<\/p>\n\n\n\n
\u901a\u8fc7\u5229\u7528\u7247\u6bb5\u7740\u8272\u5668\uff0c\u6211\u4eec\u53ef\u4ee5\u6839\u636e\u7247\u6bb5\u7684\u7a97\u53e3\u5750\u6807\uff0c\u8ba1\u7b97\u51fa\u4e0d\u540c\u7684\u989c\u8272\u3002gl_FragCoord\u7684\u4e00\u4e2a\u5e38\u89c1\u7528\u5904\u662f\u7528\u4e8e\u5bf9\u6bd4\u4e0d\u540c\u7247\u6bb5\u8ba1\u7b97\u7684\u89c6\u89c9\u8f93\u51fa\u6548\u679c\uff0c\u8fd9\u5728\u6280\u672f\u6f14\u793a\u4e2d\u53ef\u4ee5\u7ecf\u5e38\u770b\u5230\u3002\u6bd4\u5982\u8bf4\uff0c\u6211\u4eec\u80fd\u591f\u5c06\u5c4f\u5e55\u5206\u6210\u4e24\u90e8\u5206\uff0c\u5728\u7a97\u53e3\u7684\u5de6\u4fa7\u6e32\u67d3\u4e00\u79cd\u8f93\u51fa\uff0c\u5728\u7a97\u53e3\u7684\u53f3\u4fa7\u6e32\u67d3\u53e6\u4e00\u79cd\u8f93\u51fa\u3002\u4e0b\u9762\u8fd9\u4e2a\u4f8b\u5b50\u7247\u6bb5\u7740\u8272\u5668\u4f1a\u6839\u636e\u7a97\u53e3\u5750\u6807\u8f93\u51fa\u4e0d\u540c\u7684\u989c\u8272\uff1a<\/p>\n\n\n\n
void main()\n{             \n    if(gl_FragCoord.x < 400)\n        FragColor = vec4(1.0, 0.0, 0.0, 1.0);\n    else\n        FragColor = vec4(0.0, 1.0, 0.0, 1.0);        \n}\n<\/code><\/pre>\n\n\n\n
\u56e0\u4e3a\u7a97\u53e3\u7684\u5bbd\u5ea6\u662f800\u3002\u5f53\u4e00\u4e2a\u50cf\u7d20\u7684x\u5750\u6807\u5c0f\u4e8e400\u65f6\uff0c\u5b83\u4e00\u5b9a\u5728\u7a97\u53e3\u7684\u5de6\u4fa7\uff0c\u6240\u4ee5\u6211\u4eec\u7ed9\u5b83\u4e00\u4e2a\u4e0d\u540c\u7684\u989c\u8272\u3002<\/p>\n\n\n\n
\"\"\/<\/figure>\n\n\n\n
\u6211\u4eec\u73b0\u5728\u4f1a\u8ba1\u7b97\u51fa\u4e24\u4e2a\u5b8c\u5168\u4e0d\u540c\u7684\u7247\u6bb5\u7740\u8272\u5668\u7ed3\u679c\uff0c\u5e76\u5c06\u5b83\u4eec\u663e\u793a\u5728\u7a97\u53e3\u7684\u4e24\u4fa7\u3002\u4e3e\u4f8b\u6765\u8bf4\uff0c\u4f60\u53ef\u4ee5\u5c06\u5b83\u7528\u4e8e\u6d4b\u8bd5\u4e0d\u540c\u7684\u5149\u7167\u6280\u5de7\u3002<\/p>\n\n\n\n
gl_FrontFacing<\/h3>\n\n\n\n
\u7247\u6bb5\u7740\u8272\u5668\u53e6\u5916\u4e00\u4e2a\u5f88\u6709\u610f\u601d\u7684\u8f93\u5165\u53d8\u91cf\u662fgl_FrontFacing\u3002\u5728\u9762\u5254\u9664<\/a>\u6559\u7a0b\u4e2d\uff0c\u6211\u4eec\u63d0\u5230OpenGL\u80fd\u591f\u6839\u636e\u9876\u70b9\u7684\u73af\u7ed5\u987a\u5e8f\u6765\u51b3\u5b9a\u4e00\u4e2a\u9762\u662f\u6b63\u5411\u8fd8\u662f\u80cc\u5411\u9762\u3002\u5982\u679c\u6211\u4eec\u4e0d\uff08\u542f\u7528GL_FACE_CULL\u6765\uff09\u4f7f\u7528\u9762\u5254\u9664\uff0c\u90a3\u4e48gl_FrontFacing\u5c06\u4f1a\u544a\u8bc9\u6211\u4eec\u5f53\u524d\u7247\u6bb5\u662f\u5c5e\u4e8e\u6b63\u5411\u9762\u7684\u4e00\u90e8\u5206\u8fd8\u662f\u80cc\u5411\u9762\u7684\u4e00\u90e8\u5206\u3002\u4e3e\u4f8b\u6765\u8bf4\uff0c\u6211\u4eec\u80fd\u591f\u5bf9\u6b63\u5411\u9762\u8ba1\u7b97\u51fa\u4e0d\u540c\u7684\u989c\u8272\u3002<\/p>\n\n\n\n
gl_FrontFacing\u53d8\u91cf\u662f\u4e00\u4e2abool\uff0c\u5982\u679c\u5f53\u524d\u7247\u6bb5\u662f\u6b63\u5411\u9762\u7684\u4e00\u90e8\u5206\u90a3\u4e48\u5c31\u662ftrue<\/code>\uff0c\u5426\u5219\u5c31\u662ffalse<\/code>\u3002\u6bd4\u5982\u8bf4\uff0c\u6211\u4eec\u53ef\u4ee5\u8fd9\u6837\u5b50\u521b\u5efa\u4e00\u4e2a\u7acb\u65b9\u4f53\uff0c\u5728\u5185\u90e8\u548c\u5916\u90e8\u4f7f\u7528\u4e0d\u540c\u7684\u7eb9\u7406\uff1a<\/p>\n\n\n\n
#version 330 core\nout vec4 FragColor;\n\nin vec2 TexCoords;\n\nuniform sampler2D frontTexture;\nuniform sampler2D backTexture;\n\nvoid main()\n{             \n    if(gl_FrontFacing)\n        FragColor = texture(frontTexture, TexCoords);\n    else\n        FragColor = texture(backTexture, TexCoords);\n}\n<\/code><\/pre>\n\n\n\n
\u5982\u679c\u6211\u4eec\u5f80\u7bb1\u5b50\u91cc\u9762\u770b\uff0c\u5c31\u80fd\u770b\u5230\u4f7f\u7528\u7684\u662f\u4e0d\u540c\u7684\u7eb9\u7406\u3002<\/p>\n\n\n\n
\"\"\/<\/figure>\n\n\n\n
\u6ce8\u610f\uff0c\u5982\u679c\u4f60\u5f00\u542f\u4e86\u9762\u5254\u9664\uff0c\u4f60\u5c31\u770b\u4e0d\u5230\u7bb1\u5b50\u5185\u90e8\u7684\u9762\u4e86\uff0c\u6240\u4ee5\u73b0\u5728\u518d\u4f7f\u7528gl_FrontFacing\u5c31\u6ca1\u6709\u610f\u4e49\u4e86\u3002<\/p>\n\n\n\n
gl_FragDepth<\/h3>\n\n\n\n
\u8f93\u5165\u53d8\u91cfgl_FragCoord\u80fd\u8ba9\u6211\u4eec\u8bfb\u53d6\u5f53\u524d\u7247\u6bb5\u7684\u7a97\u53e3\u7a7a\u95f4\u5750\u6807\uff0c\u5e76\u83b7\u53d6\u5b83\u7684\u6df1\u5ea6\u503c\uff0c\u4f46\u662f\u5b83\u662f\u4e00\u4e2a\u53ea\u8bfb(Read-only)\u53d8\u91cf\u3002\u6211\u4eec\u4e0d\u80fd\u4fee\u6539\u7247\u6bb5\u7684\u7a97\u53e3\u7a7a\u95f4\u5750\u6807\uff0c\u4f46\u5b9e\u9645\u4e0a\u4fee\u6539\u7247\u6bb5\u7684\u6df1\u5ea6\u503c\u8fd8\u662f\u53ef\u80fd\u7684\u3002GLSL\u63d0\u4f9b\u7ed9\u6211\u4eec\u4e00\u4e2a\u53eb\u505agl_FragDepth\u7684\u8f93\u51fa\u53d8\u91cf\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u5b83\u6765\u5728\u7740\u8272\u5668\u5185\u8bbe\u7f6e\u7247\u6bb5\u7684\u6df1\u5ea6\u503c\u3002<\/p>\n\n\n\n
\u8981\u60f3\u8bbe\u7f6e\u6df1\u5ea6\u503c\uff0c\u6211\u4eec\u76f4\u63a5\u5199\u5165\u4e00\u4e2a0.0\u52301.0\u4e4b\u95f4\u7684float\u503c\u5230\u8f93\u51fa\u53d8\u91cf\u5c31\u53ef\u4ee5\u4e86\uff1a<\/p>\n\n\n\n
gl_FragDepth = 0.0; \/\/ \u8fd9\u4e2a\u7247\u6bb5\u73b0\u5728\u7684\u6df1\u5ea6\u503c\u4e3a 0.0\n<\/code><\/pre>\n\n\n\n
\u5982\u679c\u7740\u8272\u5668\u6ca1\u6709\u5199\u5165\u503c\u5230gl_FragDepth\uff0c\u5b83\u4f1a\u81ea\u52a8\u53d6\u7528gl_FragCoord.z<\/code>\u7684\u503c\u3002<\/p>\n\n\n\n
\u7136\u800c\uff0c\u7531\u6211\u4eec\u81ea\u5df1\u8bbe\u7f6e\u6df1\u5ea6\u503c\u6709\u4e00\u4e2a\u5f88\u5927\u7684\u7f3a\u70b9\uff0c\u53ea\u8981\u6211\u4eec\u5728\u7247\u6bb5\u7740\u8272\u5668\u4e2d\u5bf9gl_FragDepth\u8fdb\u884c\u5199\u5165\uff0cOpenGL\u5c31\u4f1a\uff08\u50cf\u6df1\u5ea6\u6d4b\u8bd5<\/a>\u5c0f\u8282\u4e2d\u8ba8\u8bba\u7684\u90a3\u6837\uff09\u7981\u7528\u6240\u6709\u7684\u63d0\u524d\u6df1\u5ea6\u6d4b\u8bd5(Early Depth Testing)\u3002\u5b83\u88ab\u7981\u7528\u7684\u539f\u56e0\u662f\uff0cOpenGL\u65e0\u6cd5\u5728\u7247\u6bb5\u7740\u8272\u5668\u8fd0\u884c\u4e4b\u524d<\/strong>\u5f97\u77e5\u7247\u6bb5\u5c06\u62e5\u6709\u7684\u6df1\u5ea6\u503c\uff0c\u56e0\u4e3a\u7247\u6bb5\u7740\u8272\u5668\u53ef\u80fd\u4f1a\u5b8c\u5168\u4fee\u6539\u8fd9\u4e2a\u6df1\u5ea6\u503c\u3002<\/p>\n\n\n\n
\u5728\u5199\u5165gl_FragDepth\u65f6\uff0c\u4f60\u5c31\u9700\u8981\u8003\u8651\u5230\u5b83\u6240\u5e26\u6765\u7684\u6027\u80fd\u5f71\u54cd\u3002\u7136\u800c\uff0c\u4eceOpenGL 4.2\u8d77\uff0c\u6211\u4eec\u4ecd\u53ef\u4ee5\u5bf9\u4e24\u8005\u8fdb\u884c\u4e00\u5b9a\u7684\u8c03\u548c\uff0c\u5728\u7247\u6bb5\u7740\u8272\u5668\u7684\u9876\u90e8\u4f7f\u7528\u6df1\u5ea6\u6761\u4ef6(Depth Condition)\u91cd\u65b0\u58f0\u660egl_FragDepth\u53d8\u91cf\uff1a<\/p>\n\n\n\n
layout (depth_<condition>) out float gl_FragDepth;\n<\/code><\/pre>\n\n\n\n
condition<\/code>\u53ef\u4ee5\u4e3a\u4e0b\u9762\u7684\u503c\uff1a<\/p>\n\n\n\n
\u6761\u4ef6<\/th>\u63cf\u8ff0<\/th><\/tr><\/thead>
any<\/code><\/td>\u9ed8\u8ba4\u503c\u3002\u63d0\u524d\u6df1\u5ea6\u6d4b\u8bd5\u662f\u7981\u7528\u7684\uff0c\u4f60\u4f1a\u635f\u5931\u5f88\u591a\u6027\u80fd<\/td><\/tr>
greater<\/code><\/td>\u4f60\u53ea\u80fd\u8ba9\u6df1\u5ea6\u503c\u6bd4gl_FragCoord.z<\/code>\u66f4\u5927<\/td><\/tr>
less<\/code><\/td>\u4f60\u53ea\u80fd\u8ba9\u6df1\u5ea6\u503c\u6bd4gl_FragCoord.z<\/code>\u66f4\u5c0f<\/td><\/tr>
unchanged<\/code><\/td>\u5982\u679c\u4f60\u8981\u5199\u5165gl_FragDepth<\/code>\uff0c\u4f60\u5c06\u53ea\u80fd\u5199\u5165gl_FragCoord.z<\/code>\u7684\u503c<\/td><\/tr><\/tbody><\/table>\n\n\n\n
\u901a\u8fc7\u5c06\u6df1\u5ea6\u6761\u4ef6\u8bbe\u7f6e\u4e3agreater<\/code>\u6216\u8005less<\/code>\uff0cOpenGL\u5c31\u80fd\u5047\u8bbe\u4f60\u53ea\u4f1a\u5199\u5165\u6bd4\u5f53\u524d\u7247\u6bb5\u6df1\u5ea6\u503c\u66f4\u5927\u6216\u8005\u66f4\u5c0f\u7684\u503c\u4e86\u3002\u8fd9\u6837\u5b50\u7684\u8bdd\uff0c\u5f53\u6df1\u5ea6\u503c\u6bd4\u7247\u6bb5\u7684\u6df1\u5ea6\u503c\u8981\u5c0f\u7684\u65f6\u5019\uff0cOpenGL\u4ecd\u662f\u80fd\u591f\u8fdb\u884c\u63d0\u524d\u6df1\u5ea6\u6d4b\u8bd5\u7684\u3002<\/p>\n\n\n\n
\u4e0b\u9762\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u5bf9\u7247\u6bb5\u7684\u6df1\u5ea6\u503c\u8fdb\u884c\u4e86\u9012\u589e\uff0c\u4f46\u4ecd\u7136\u4e5f\u4fdd\u7559\u4e86\u4e00\u4e9b\u63d0\u524d\u6df1\u5ea6\u6d4b\u8bd5\uff1a<\/p>\n\n\n\n
#version 420 core \/\/ \u6ce8\u610fGLSL\u7684\u7248\u672c\uff01\nout vec4 FragColor;\nlayout (depth_greater) out float gl_FragDepth;\n\nvoid main()\n{             \n    FragColor = vec4(1.0);\n    gl_FragDepth = gl_FragCoord.z + 0.1;\n}  \n<\/code><\/pre>\n\n\n\n
\u6ce8\u610f\u8fd9\u4e2a\u7279\u6027\u53ea\u5728OpenGL 4.2\u7248\u672c\u6216\u4ee5\u4e0a\u624d\u63d0\u4f9b\u3002<\/p>\n\n\n\n
\u63a5\u53e3\u5757<\/h1>\n\n\n\n
\u5230\u76ee\u524d\u4e3a\u6b62\uff0c\u6bcf\u5f53\u6211\u4eec\u5e0c\u671b\u4ece\u9876\u70b9\u7740\u8272\u5668\u5411\u7247\u6bb5\u7740\u8272\u5668\u53d1\u9001\u6570\u636e\u65f6\uff0c\u6211\u4eec\u90fd\u58f0\u660e\u4e86\u51e0\u4e2a\u5bf9\u5e94\u7684\u8f93\u5165\/\u8f93\u51fa\u53d8\u91cf\u3002\u5c06\u5b83\u4eec\u4e00\u4e2a\u4e00\u4e2a\u58f0\u660e\u662f\u7740\u8272\u5668\u95f4\u53d1\u9001\u6570\u636e\u6700\u7b80\u5355\u7684\u65b9\u5f0f\u4e86\uff0c\u4f46\u5f53\u7a0b\u5e8f\u53d8\u5f97\u66f4\u5927\u65f6\uff0c\u4f60\u5e0c\u671b\u53d1\u9001\u7684\u53ef\u80fd\u5c31\u4e0d\u53ea\u662f\u51e0\u4e2a\u53d8\u91cf\u4e86\uff0c\u5b83\u8fd8\u53ef\u80fd\u5305\u62ec\u6570\u7ec4\u548c\u7ed3\u6784\u4f53\u3002<\/p>\n\n\n\n
\u4e3a\u4e86\u5e2e\u52a9\u6211\u4eec\u7ba1\u7406\u8fd9\u4e9b\u53d8\u91cf\uff0cGLSL\u4e3a\u6211\u4eec\u63d0\u4f9b\u4e86\u4e00\u4e2a\u53eb\u505a\u63a5\u53e3\u5757(Interface Block)\u7684\u4e1c\u897f\uff0c\u6765\u65b9\u4fbf\u6211\u4eec\u7ec4\u5408\u8fd9\u4e9b\u53d8\u91cf\u3002\u63a5\u53e3\u5757\u7684\u58f0\u660e\u548cstruct\u7684\u58f0\u660e\u6709\u70b9\u76f8\u50cf\uff0c\u4e0d\u540c\u7684\u662f\uff0c\u73b0\u5728\u6839\u636e\u5b83\u662f\u4e00\u4e2a\u8f93\u5165\u8fd8\u662f\u8f93\u51fa\u5757(Block)\uff0c\u4f7f\u7528in\u6216out\u5173\u952e\u5b57\u6765\u5b9a\u4e49\u7684\u3002<\/p>\n\n\n\n
#version 330 core\nlayout (location = 0) in vec3 aPos;\nlayout (location = 1) in vec2 aTexCoords;\n\nuniform mat4 model;\nuniform mat4 view;\nuniform mat4 projection;\n\nout VS_OUT\n{\n    vec2 TexCoords;\n} vs_out;\n\nvoid main()\n{\n    gl_Position = projection * view * model * vec4(aPos, 1.0);    \n    vs_out.TexCoords = aTexCoords;\n}  \n<\/code><\/pre>\n\n\n\n
\u8fd9\u6b21\u6211\u4eec\u58f0\u660e\u4e86\u4e00\u4e2a\u53eb\u505avs_out\u7684\u63a5\u53e3\u5757\uff0c\u5b83\u6253\u5305\u4e86\u6211\u4eec\u5e0c\u671b\u53d1\u9001\u5230\u4e0b\u4e00\u4e2a\u7740\u8272\u5668\u4e2d\u7684\u6240\u6709\u8f93\u51fa\u53d8\u91cf\u3002\u8fd9\u53ea\u662f\u4e00\u4e2a\u5f88\u7b80\u5355\u7684\u4f8b\u5b50\uff0c\u4f46\u4f60\u53ef\u4ee5\u60f3\u8c61\u4e00\u4e0b\uff0c\u5b83\u80fd\u591f\u5e2e\u52a9\u4f60\u7ba1\u7406\u7740\u8272\u5668\u7684\u8f93\u5165\u548c\u8f93\u51fa\u3002\u5f53\u6211\u4eec\u5e0c\u671b\u5c06\u7740\u8272\u5668\u7684\u8f93\u5165\u6216\u8f93\u51fa\u6253\u5305\u4e3a\u6570\u7ec4\u65f6\uff0c\u5b83\u4e5f\u4f1a\u975e\u5e38\u6709\u7528\uff0c\u6211\u4eec\u5c06\u5728\u4e0b\u4e00\u8282<\/a>\u8ba8\u8bba\u51e0\u4f55\u7740\u8272\u5668(Geometry Shader)\u65f6\u89c1\u5230\u3002<\/p>\n\n\n\n
\u4e4b\u540e\uff0c\u6211\u4eec\u8fd8\u9700\u8981\u5728\u4e0b\u4e00\u4e2a\u7740\u8272\u5668\uff0c\u5373\u7247\u6bb5\u7740\u8272\u5668\uff0c\u4e2d\u5b9a\u4e49\u4e00\u4e2a\u8f93\u5165\u63a5\u53e3\u5757\u3002\u5757\u540d(Block Name)\u5e94\u8be5\u662f\u548c\u7740\u8272\u5668\u4e2d\u4e00\u6837\u7684\uff08VS_OUT\uff09\uff0c\u4f46\u5b9e\u4f8b\u540d(Instance Name)\uff08\u9876\u70b9\u7740\u8272\u5668\u4e2d\u7528\u7684\u662fvs_out\uff09\u53ef\u4ee5\u662f\u968f\u610f\u7684\uff0c\u4f46\u8981\u907f\u514d\u4f7f\u7528\u8bef\u5bfc\u6027\u7684\u540d\u79f0\uff0c\u6bd4\u5982\u5bf9\u5b9e\u9645\u4e0a\u5305\u542b\u8f93\u5165\u53d8\u91cf\u7684\u63a5\u53e3\u5757\u547d\u540d\u4e3avs_out\u3002<\/p>\n\n\n\n
#version 330 core\nout vec4 FragColor;\n\nin VS_OUT\n{\n    vec2 TexCoords;\n} fs_in;\n\nuniform sampler2D texture;\n\nvoid main()\n{             \n    FragColor = texture(texture, fs_in.TexCoords);   \n}\n<\/code><\/pre>\n\n\n\n
\u53ea\u8981\u4e24\u4e2a\u63a5\u53e3\u5757\u7684\u540d\u5b57\u4e00\u6837\uff0c\u5b83\u4eec\u5bf9\u5e94\u7684\u8f93\u5165\u548c\u8f93\u51fa\u5c06\u4f1a\u5339\u914d\u8d77\u6765\u3002\u8fd9\u662f\u5e2e\u52a9\u4f60\u7ba1\u7406\u4ee3\u7801\u7684\u53c8\u4e00\u4e2a\u6709\u7528\u7279\u6027\uff0c\u5b83\u5728\u51e0\u4f55\u7740\u8272\u5668\u8fd9\u6837\u7a7f\u63d2\u7279\u5b9a\u7740\u8272\u5668\u9636\u6bb5\u7684\u573a\u666f\u4e0b\u4f1a\u5f88\u6709\u7528\u3002<\/p>\n\n\n\n
Uniform\u7f13\u51b2\u5bf9\u8c61<\/h1>\n\n\n\n
\u6211\u4eec\u5df2\u7ecf\u4f7f\u7528OpenGL\u5f88\u957f\u65f6\u95f4\u4e86\uff0c\u5b66\u4f1a\u4e86\u4e00\u4e9b\u5f88\u9177\u7684\u6280\u5de7\uff0c\u4f46\u4e5f\u9047\u5230\u4e86\u4e00\u4e9b\u5f88\u9ebb\u70e6\u7684\u5730\u65b9\u3002\u6bd4\u5982\u8bf4\uff0c\u5f53\u4f7f\u7528\u591a\u4e8e\u4e00\u4e2a\u7684\u7740\u8272\u5668\u65f6\uff0c\u5c3d\u7ba1\u5927\u90e8\u5206\u7684uniform\u53d8\u91cf\u90fd\u662f\u76f8\u540c\u7684\uff0c\u6211\u4eec\u8fd8\u662f\u9700\u8981\u4e0d\u65ad\u5730\u8bbe\u7f6e\u5b83\u4eec\uff0c\u6240\u4ee5\u4e3a\u4ec0\u4e48\u8981\u8fd9\u4e48\u9ebb\u70e6\u5730\u91cd\u590d\u8bbe\u7f6e\u5b83\u4eec\u5462\uff1f<\/p>\n\n\n\n
OpenGL\u4e3a\u6211\u4eec\u63d0\u4f9b\u4e86\u4e00\u4e2a\u53eb\u505aUniform\u7f13\u51b2\u5bf9\u8c61(Uniform Buffer Object)\u7684\u5de5\u5177\uff0c\u5b83\u5141\u8bb8\u6211\u4eec\u5b9a\u4e49\u4e00\u7cfb\u5217\u5728\u591a\u4e2a\u7740\u8272\u5668\u4e2d\u76f8\u540c\u7684\u5168\u5c40<\/strong>Uniform\u53d8\u91cf\u3002\u5f53\u4f7f\u7528Uniform\u7f13\u51b2\u5bf9\u8c61\u7684\u65f6\u5019\uff0c\u6211\u4eec\u53ea\u9700\u8981\u8bbe\u7f6e\u76f8\u5173\u7684uniform\u4e00\u6b21<\/strong>\u3002\u5f53\u7136\uff0c\u6211\u4eec\u4ecd\u9700\u8981\u624b\u52a8\u8bbe\u7f6e\u6bcf\u4e2a\u7740\u8272\u5668\u4e2d\u4e0d\u540c\u7684uniform\u3002\u5e76\u4e14\u521b\u5efa\u548c\u914d\u7f6eUniform\u7f13\u51b2\u5bf9\u8c61\u4f1a\u6709\u4e00\u70b9\u7e41\u7410\u3002<\/p>\n\n\n\n
\u56e0\u4e3aUniform\u7f13\u51b2\u5bf9\u8c61\u4ecd\u662f\u4e00\u4e2a\u7f13\u51b2\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528glGenBuffers\u6765\u521b\u5efa\u5b83\uff0c\u5c06\u5b83\u7ed1\u5b9a\u5230GL_UNIFORM_BUFFER\u7f13\u51b2\u76ee\u6807\uff0c\u5e76\u5c06\u6240\u6709\u76f8\u5173\u7684uniform\u6570\u636e\u5b58\u5165\u7f13\u51b2\u3002\u5728Uniform\u7f13\u51b2\u5bf9\u8c61\u4e2d\u50a8\u5b58\u6570\u636e\u662f\u6709\u4e00\u4e9b\u89c4\u5219\u7684\uff0c\u6211\u4eec\u5c06\u4f1a\u5728\u4e4b\u540e\u8ba8\u8bba\u5b83\u3002\u9996\u5148\uff0c\u6211\u4eec\u5c06\u4f7f\u7528\u4e00\u4e2a\u7b80\u5355\u7684\u9876\u70b9\u7740\u8272\u5668\uff0c\u5c06projection\u548cview\u77e9\u9635\u5b58\u50a8\u5230\u6240\u8c13\u7684Uniform\u5757(Uniform Block)\u4e2d\uff1a<\/p>\n\n\n\n
#version 330 core\nlayout (location = 0) in vec3 aPos;\n\nlayout (std140) uniform Matrices\n{\n    mat4 projection;\n    mat4 view;\n};\n\nuniform mat4 model;\n\nvoid main()\n{\n    gl_Position = projection * view * model * vec4(aPos, 1.0);\n}\n<\/code><\/pre>\n\n\n\n
\u5728\u6211\u4eec\u5927\u591a\u6570\u7684\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u90fd\u4f1a\u5728\u6bcf\u4e2a\u6e32\u67d3\u8fed\u4ee3\u4e2d\uff0c\u5bf9\u6bcf\u4e2a\u7740\u8272\u5668\u8bbe\u7f6eprojection\u548cview Uniform\u77e9\u9635\u3002\u8fd9\u662f\u5229\u7528Uniform\u7f13\u51b2\u5bf9\u8c61\u7684\u4e00\u4e2a\u975e\u5e38\u5b8c\u7f8e\u7684\u4f8b\u5b50\uff0c\u56e0\u4e3a\u73b0\u5728\u6211\u4eec\u53ea\u9700\u8981\u5b58\u50a8\u8fd9\u4e9b\u77e9\u9635\u4e00\u6b21\u5c31\u53ef\u4ee5\u4e86\u3002<\/p>\n\n\n\n
\u8fd9\u91cc\uff0c\u6211\u4eec\u58f0\u660e\u4e86\u4e00\u4e2a\u53eb\u505aMatrices\u7684Uniform\u5757\uff0c\u5b83\u50a8\u5b58\u4e86\u4e24\u4e2a4×4\u77e9\u9635\u3002Uniform\u5757\u4e2d\u7684\u53d8\u91cf\u53ef\u4ee5\u76f4\u63a5\u8bbf\u95ee\uff0c\u4e0d\u9700\u8981\u52a0\u5757\u540d\u4f5c\u4e3a\u524d\u7f00\u3002\u63a5\u4e0b\u6765\uff0c\u6211\u4eec\u5728OpenGL\u4ee3\u7801\u4e2d\u5c06\u8fd9\u4e9b\u77e9\u9635\u503c\u5b58\u5165\u7f13\u51b2\u4e2d\uff0c\u6bcf\u4e2a\u58f0\u660e\u4e86\u8fd9\u4e2aUniform\u5757\u7684\u7740\u8272\u5668\u90fd\u80fd\u591f\u8bbf\u95ee\u8fd9\u4e9b\u77e9\u9635\u3002<\/p>\n\n\n\n
\u4f60\u73b0\u5728\u53ef\u80fd\u4f1a\u5728\u60f3layout (std140)<\/code>\u8fd9\u4e2a\u8bed\u53e5\u662f\u4ec0\u4e48\u610f\u601d\u3002\u5b83\u7684\u610f\u601d\u662f\u8bf4\uff0c\u5f53\u524d\u5b9a\u4e49\u7684Uniform\u5757\u5bf9\u5b83\u7684\u5185\u5bb9\u4f7f\u7528\u4e00\u4e2a\u7279\u5b9a\u7684\u5185\u5b58\u5e03\u5c40\u3002\u8fd9\u4e2a\u8bed\u53e5\u8bbe\u7f6e\u4e86Uniform\u5757\u5e03\u5c40(Uniform Block Layout)\u3002<\/p>\n\n\n\n
Uniform\u5757\u5e03\u5c40<\/h2>\n\n\n\n
Uniform\u5757\u7684\u5185\u5bb9\u662f\u50a8\u5b58\u5728\u4e00\u4e2a\u7f13\u51b2\u5bf9\u8c61\u4e2d\u7684\uff0c\u5b83\u5b9e\u9645\u4e0a\u53ea\u662f\u4e00\u5757\u9884\u7559\u5185\u5b58\u3002\u56e0\u4e3a\u8fd9\u5757\u5185\u5b58\u5e76\u4e0d\u4f1a\u4fdd\u5b58\u5b83\u5177\u4f53\u4fdd\u5b58\u7684\u662f\u4ec0\u4e48\u7c7b\u578b\u7684\u6570\u636e\uff0c\u6211\u4eec\u8fd8\u9700\u8981\u544a\u8bc9OpenGL\u5185\u5b58\u7684\u54ea\u4e00\u90e8\u5206\u5bf9\u5e94\u7740\u7740\u8272\u5668\u4e2d\u7684\u54ea\u4e00\u4e2auniform\u53d8\u91cf\u3002<\/p>\n\n\n\n
\u5047\u8bbe\u7740\u8272\u5668\u4e2d\u6709\u4ee5\u4e0b\u7684\u8fd9\u4e2aUniform\u5757\uff1a<\/p>\n\n\n\n
layout (std140) uniform ExampleBlock\n{\n    float value;\n    vec3  vector;\n    mat4  matrix;\n    float values[3];\n    bool  boolean;\n    int   integer;\n};\n<\/code><\/pre>\n\n\n\n
\u6211\u4eec\u9700\u8981\u77e5\u9053\u7684\u662f\u6bcf\u4e2a\u53d8\u91cf\u7684\u5927\u5c0f\uff08\u5b57\u8282\uff09\u548c\uff08\u4ece\u5757\u8d77\u59cb\u4f4d\u7f6e\u7684\uff09\u504f\u79fb\u91cf\uff0c\u6765\u8ba9\u6211\u4eec\u80fd\u591f\u6309\u987a\u5e8f\u5c06\u5b83\u4eec\u653e\u8fdb\u7f13\u51b2\u4e2d\u3002\u6bcf\u4e2a\u5143\u7d20\u7684\u5927\u5c0f\u90fd\u662f\u5728OpenGL\u4e2d\u6709\u6e05\u695a\u5730\u58f0\u660e\u7684\uff0c\u800c\u4e14\u76f4\u63a5\u5bf9\u5e94C++\u6570\u636e\u7c7b\u578b\uff0c\u5176\u4e2d\u5411\u91cf\u548c\u77e9\u9635\u90fd\u662f\u5927\u7684float\u6570\u7ec4\u3002OpenGL\u6ca1\u6709\u58f0\u660e\u7684\u662f\u8fd9\u4e9b\u53d8\u91cf\u95f4\u7684\u95f4\u8ddd(Spacing)\u3002\u8fd9\u5141\u8bb8\u786c\u4ef6\u80fd\u591f\u5728\u5b83\u8ba4\u4e3a\u5408\u9002\u7684\u4f4d\u7f6e\u653e\u7f6e\u53d8\u91cf\u3002\u6bd4\u5982\u8bf4\uff0c\u4e00\u4e9b\u786c\u4ef6\u53ef\u80fd\u4f1a\u5c06\u4e00\u4e2avec3\u653e\u7f6e\u5728float\u8fb9\u4e0a\u3002\u4e0d\u662f\u6240\u6709\u7684\u786c\u4ef6\u90fd\u80fd\u8fd9\u6837\u5904\u7406\uff0c\u53ef\u80fd\u4f1a\u5728\u9644\u52a0\u8fd9\u4e2afloat\u4e4b\u524d\uff0c\u5148\u5c06vec3\u586b\u5145(Pad)\u4e3a\u4e00\u4e2a4\u4e2afloat\u7684\u6570\u7ec4\u3002\u8fd9\u4e2a\u7279\u6027\u672c\u8eab\u5f88\u68d2\uff0c\u4f46\u662f\u4f1a\u5bf9\u6211\u4eec\u9020\u6210\u9ebb\u70e6\u3002<\/p>\n\n\n\n
\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0cGLSL\u4f1a\u4f7f\u7528\u4e00\u4e2a\u53eb\u505a\u5171\u4eab(Shared)\u5e03\u5c40\u7684Uniform\u5185\u5b58\u5e03\u5c40\uff0c\u5171\u4eab\u662f\u56e0\u4e3a\u4e00\u65e6\u786c\u4ef6\u5b9a\u4e49\u4e86\u504f\u79fb\u91cf\uff0c\u5b83\u4eec\u5728\u591a\u4e2a\u7a0b\u5e8f\u4e2d\u662f\u5171\u4eab<\/strong>\u5e76\u4e00\u81f4\u7684\u3002\u4f7f\u7528\u5171\u4eab\u5e03\u5c40\u65f6\uff0cGLSL\u662f\u53ef\u4ee5\u4e3a\u4e86\u4f18\u5316\u800c\u5bf9uniform\u53d8\u91cf\u7684\u4f4d\u7f6e\u8fdb\u884c\u53d8\u52a8\u7684\uff0c\u53ea\u8981\u53d8\u91cf\u7684\u987a\u5e8f\u4fdd\u6301\u4e0d\u53d8\u3002\u56e0\u4e3a\u6211\u4eec\u65e0\u6cd5\u77e5\u9053\u6bcf\u4e2auniform\u53d8\u91cf\u7684\u504f\u79fb\u91cf\uff0c\u6211\u4eec\u4e5f\u5c31\u4e0d\u77e5\u9053\u5982\u4f55\u51c6\u786e\u5730\u586b\u5145\u6211\u4eec\u7684Uniform\u7f13\u51b2\u4e86\u3002\u6211\u4eec\u80fd\u591f\u4f7f\u7528\u50cf\u662fglGetUniformIndices\u8fd9\u6837\u7684\u51fd\u6570\u6765\u67e5\u8be2\u8fd9\u4e2a\u4fe1\u606f\uff0c\u4f46\u8fd9\u8d85\u51fa\u672c\u8282\u7684\u8303\u56f4\u4e86\u3002<\/p>\n\n\n\n
\u867d\u7136\u5171\u4eab\u5e03\u5c40\u7ed9\u4e86\u6211\u4eec\u5f88\u591a\u8282\u7701\u7a7a\u95f4\u7684\u4f18\u5316\uff0c\u4f46\u662f\u6211\u4eec\u9700\u8981\u67e5\u8be2\u6bcf\u4e2auniform\u53d8\u91cf\u7684\u504f\u79fb\u91cf\uff0c\u8fd9\u4f1a\u4ea7\u751f\u975e\u5e38\u591a\u7684\u5de5\u4f5c\u91cf\u3002\u901a\u5e38\u7684\u505a\u6cd5\u662f\uff0c\u4e0d\u4f7f\u7528\u5171\u4eab\u5e03\u5c40\uff0c\u800c\u662f\u4f7f\u7528std140\u5e03\u5c40\u3002std140\u5e03\u5c40\u58f0\u660e\u4e86\u6bcf\u4e2a\u53d8\u91cf\u7684\u504f\u79fb\u91cf\u90fd\u662f\u7531\u4e00\u7cfb\u5217\u89c4\u5219\u6240\u51b3\u5b9a\u7684\uff0c\u8fd9\u663e\u5f0f\u5730<\/strong>\u58f0\u660e\u4e86\u6bcf\u4e2a\u53d8\u91cf\u7c7b\u578b\u7684\u5185\u5b58\u5e03\u5c40\u3002\u7531\u4e8e\u8fd9\u662f\u663e\u5f0f\u63d0\u53ca\u7684\uff0c\u6211\u4eec\u53ef\u4ee5\u624b\u52a8\u8ba1\u7b97\u51fa\u6bcf\u4e2a\u53d8\u91cf\u7684\u504f\u79fb\u91cf\u3002<\/p>\n\n\n\n
\u6bcf\u4e2a\u53d8\u91cf\u90fd\u6709\u4e00\u4e2a\u57fa\u51c6\u5bf9\u9f50\u91cf(Base Alignment)\uff0c\u5b83\u7b49\u4e8e\u4e00\u4e2a\u53d8\u91cf\u5728Uniform\u5757\u4e2d\u6240\u5360\u636e\u7684\u7a7a\u95f4\uff08\u5305\u62ec\u586b\u5145\u91cf(Padding)\uff09\uff0c\u8fd9\u4e2a\u57fa\u51c6\u5bf9\u9f50\u91cf\u662f\u4f7f\u7528std140\u5e03\u5c40\u7684\u89c4\u5219\u8ba1\u7b97\u51fa\u6765\u7684\u3002\u63a5\u4e0b\u6765\uff0c\u5bf9\u6bcf\u4e2a\u53d8\u91cf\uff0c\u6211\u4eec\u518d\u8ba1\u7b97\u5b83\u7684\u5bf9\u9f50\u504f\u79fb\u91cf(Aligned Offset)\uff0c\u5b83\u662f\u4e00\u4e2a\u53d8\u91cf\u4ece\u5757\u8d77\u59cb\u4f4d\u7f6e\u7684\u5b57\u8282\u504f\u79fb\u91cf\u3002\u4e00\u4e2a\u53d8\u91cf\u7684\u5bf9\u9f50\u5b57\u8282\u504f\u79fb\u91cf\u5fc5\u987b<\/strong>\u7b49\u4e8e\u57fa\u51c6\u5bf9\u9f50\u91cf\u7684\u500d\u6570\u3002<\/p>\n\n\n\n
\u5e03\u5c40\u89c4\u5219\u7684\u539f\u6587\u53ef\u4ee5\u5728OpenGL\u7684Uniform\u7f13\u51b2\u89c4\u8303\u8fd9\u91cc<\/a>\u627e\u5230\uff0c\u4f46\u6211\u4eec\u5c06\u4f1a\u5728\u4e0b\u9762\u5217\u51fa\u6700\u5e38\u89c1\u7684\u89c4\u5219\u3002GLSL\u4e2d\u7684\u6bcf\u4e2a\u53d8\u91cf\uff0c\u6bd4\u5982\u8bf4int\u3001float\u548cbool\uff0c\u90fd\u88ab\u5b9a\u4e49\u4e3a4\u5b57\u8282\u91cf\u3002\u6bcf4\u4e2a\u5b57\u8282\u5c06\u4f1a\u7528\u4e00\u4e2aN<\/code>\u6765\u8868\u793a\u3002<\/p>\n\n\n\n
\u7c7b\u578b<\/th>\u5e03\u5c40\u89c4\u5219<\/th><\/tr><\/thead>
\u6807\u91cf\uff0c\u6bd4\u5982int\u548cbool<\/td>\u6bcf\u4e2a\u6807\u91cf\u7684\u57fa\u51c6\u5bf9\u9f50\u91cf\u4e3aN\u3002<\/td><\/tr>
\u5411\u91cf<\/td>2N\u6216\u80054N\u3002\u8fd9\u610f\u5473\u7740vec3\u7684\u57fa\u51c6\u5bf9\u9f50\u91cf\u4e3a4N\u3002<\/td><\/tr>
\u6807\u91cf\u6216\u5411\u91cf\u7684\u6570\u7ec4<\/td>\u6bcf\u4e2a\u5143\u7d20\u7684\u57fa\u51c6\u5bf9\u9f50\u91cf\u4e0evec4\u7684\u76f8\u540c\u3002<\/td><\/tr>
\u77e9\u9635<\/td>\u50a8\u5b58\u4e3a\u5217\u5411\u91cf\u7684\u6570\u7ec4\uff0c\u6bcf\u4e2a\u5411\u91cf\u7684\u57fa\u51c6\u5bf9\u9f50\u91cf\u4e0evec4\u7684\u76f8\u540c\u3002<\/td><\/tr>
\u7ed3\u6784\u4f53<\/td>\u7b49\u4e8e\u6240\u6709\u5143\u7d20\u6839\u636e\u89c4\u5219\u8ba1\u7b97\u540e\u7684\u5927\u5c0f\uff0c\u4f46\u4f1a\u586b\u5145\u5230vec4\u5927\u5c0f\u7684\u500d\u6570\u3002<\/td><\/tr><\/tbody><\/table>\n\n\n\n
\u548cOpenGL\u5927\u591a\u6570\u7684\u89c4\u8303\u4e00\u6837\uff0c\u4f7f\u7528\u4f8b\u5b50\u5c31\u80fd\u66f4\u5bb9\u6613\u5730\u7406\u89e3\u3002\u6211\u4eec\u4f1a\u4f7f\u7528\u4e4b\u524d\u5f15\u5165\u7684\u90a3\u4e2a\u53eb\u505aExampleBlock\u7684Uniform\u5757\uff0c\u5e76\u4f7f\u7528std140\u5e03\u5c40\u8ba1\u7b97\u51fa\u6bcf\u4e2a\u6210\u5458\u7684\u5bf9\u9f50\u504f\u79fb\u91cf\uff1a<\/p>\n\n\n\n
layout (std140) uniform ExampleBlock\n{\n                     \/\/ \u57fa\u51c6\u5bf9\u9f50\u91cf       \/\/ \u5bf9\u9f50\u504f\u79fb\u91cf\n    float value;     \/\/ 4               \/\/ 0 \n    vec3 vector;     \/\/ 16              \/\/ 16  (\u5fc5\u987b\u662f16\u7684\u500d\u6570\uff0c\u6240\u4ee5 4->16)\n    mat4 matrix;     \/\/ 16              \/\/ 32  (\u5217 0)\n                     \/\/ 16              \/\/ 48  (\u5217 1)\n                     \/\/ 16              \/\/ 64  (\u5217 2)\n                     \/\/ 16              \/\/ 80  (\u5217 3)\n    float values[3]; \/\/ 16              \/\/ 96  (values[0])\n                     \/\/ 16              \/\/ 112 (values[1])\n                     \/\/ 16              \/\/ 128 (values[2])\n    bool boolean;    \/\/ 4               \/\/ 144\n    int integer;     \/\/ 4               \/\/ 148\n}; \n<\/code><\/pre>\n\n\n\n
\u4f5c\u4e3a\u7ec3\u4e60\uff0c\u5c1d\u8bd5\u53bb\u81ea\u5df1\u8ba1\u7b97\u4e00\u4e0b\u504f\u79fb\u91cf\uff0c\u5e76\u548c\u8868\u683c\u8fdb\u884c\u5bf9\u6bd4\u3002\u4f7f\u7528\u8ba1\u7b97\u540e\u7684\u504f\u79fb\u91cf\u503c\uff0c\u6839\u636estd140\u5e03\u5c40\u7684\u89c4\u5219\uff0c\u6211\u4eec\u5c31\u80fd\u4f7f\u7528\u50cf\u662fglBufferSubData\u7684\u51fd\u6570\u5c06\u53d8\u91cf\u6570\u636e\u6309\u7167\u504f\u79fb\u91cf\u586b\u5145\u8fdb\u7f13\u51b2\u4e2d\u4e86\u3002\u867d\u7136std140\u5e03\u5c40\u4e0d\u662f\u6700\u9ad8\u6548\u7684\u5e03\u5c40\uff0c\u4f46\u5b83\u4fdd\u8bc1\u4e86\u5185\u5b58\u5e03\u5c40\u5728\u6bcf\u4e2a\u58f0\u660e\u4e86\u8fd9\u4e2aUniform\u5757\u7684\u7a0b\u5e8f\u4e2d\u662f\u4e00\u81f4\u7684\u3002<\/p>\n\n\n\n
\u901a\u8fc7\u5728Uniform\u5757\u5b9a\u4e49\u4e4b\u524d\u6dfb\u52a0layout (std140)<\/code>\u8bed\u53e5\uff0c\u6211\u4eec\u544a\u8bc9OpenGL\u8fd9\u4e2aUniform\u5757\u4f7f\u7528\u7684\u662fstd140\u5e03\u5c40\u3002\u9664\u6b64\u4e4b\u5916\u8fd8\u53ef\u4ee5\u9009\u62e9\u4e24\u4e2a\u5e03\u5c40\uff0c\u4f46\u5b83\u4eec\u90fd\u9700\u8981\u6211\u4eec\u5728\u586b\u5145\u7f13\u51b2\u4e4b\u524d\u5148\u67e5\u8be2\u6bcf\u4e2a\u504f\u79fb\u91cf\u3002\u6211\u4eec\u5df2\u7ecf\u89c1\u8fc7shared<\/code>\u5e03\u5c40\u4e86\uff0c\u5269\u4e0b\u7684\u4e00\u4e2a\u5e03\u5c40\u662fpacked<\/code>\u3002\u5f53\u4f7f\u7528\u7d27\u51d1(Packed)\u5e03\u5c40\u65f6\uff0c\u662f\u4e0d\u80fd\u4fdd\u8bc1\u8fd9\u4e2a\u5e03\u5c40\u5728\u6bcf\u4e2a\u7a0b\u5e8f\u4e2d\u4fdd\u6301\u4e0d\u53d8\u7684\uff08\u5373\u975e\u5171\u4eab\uff09\uff0c\u56e0\u4e3a\u5b83\u5141\u8bb8\u7f16\u8bd1\u5668\u53bb\u5c06uniform\u53d8\u91cf\u4eceUniform\u5757\u4e2d\u4f18\u5316\u6389\uff0c\u8fd9\u5728\u6bcf\u4e2a\u7740\u8272\u5668\u4e2d\u90fd\u53ef\u80fd\u662f\u4e0d\u540c\u7684\u3002<\/p>\n\n\n\n
\u4f7f\u7528Uniform\u7f13\u51b2<\/h2>\n\n\n\n
\u6211\u4eec\u5df2\u7ecf\u8ba8\u8bba\u4e86\u5982\u4f55\u5728\u7740\u8272\u5668\u4e2d\u5b9a\u4e49Uniform\u5757\uff0c\u5e76\u8bbe\u5b9a\u5b83\u4eec\u7684\u5185\u5b58\u5e03\u5c40\u4e86\uff0c\u4f46\u6211\u4eec\u8fd8\u6ca1\u6709\u8ba8\u8bba\u8be5\u5982\u4f55\u4f7f\u7528\u5b83\u4eec\u3002<\/p>\n\n\n\n
\u9996\u5148\uff0c\u6211\u4eec\u9700\u8981\u8c03\u7528glGenBuffers\uff0c\u521b\u5efa\u4e00\u4e2aUniform\u7f13\u51b2\u5bf9\u8c61\u3002\u4e00\u65e6\u6211\u4eec\u6709\u4e86\u4e00\u4e2a\u7f13\u51b2\u5bf9\u8c61\uff0c\u6211\u4eec\u9700\u8981\u5c06\u5b83\u7ed1\u5b9a\u5230GL_UNIFORM_BUFFER\u76ee\u6807\uff0c\u5e76\u8c03\u7528glBufferData\uff0c\u5206\u914d\u8db3\u591f\u7684\u5185\u5b58\u3002<\/p>\n\n\n\n
unsigned int uboExampleBlock;\nglGenBuffers(1, &uboExampleBlock);\nglBindBuffer(GL_UNIFORM_BUFFER, uboExampleBlock);\nglBufferData(GL_UNIFORM_BUFFER, 152, NULL, GL_STATIC_DRAW); \/\/ \u5206\u914d152\u5b57\u8282\u7684\u5185\u5b58\nglBindBuffer(GL_UNIFORM_BUFFER, 0);\n<\/code><\/pre>\n\n\n\n
\u73b0\u5728\uff0c\u6bcf\u5f53\u6211\u4eec\u9700\u8981\u5bf9\u7f13\u51b2\u66f4\u65b0\u6216\u8005\u63d2\u5165\u6570\u636e\uff0c\u6211\u4eec\u90fd\u4f1a\u7ed1\u5b9a\u5230uboExampleBlock\uff0c\u5e76\u4f7f\u7528glBufferSubData\u6765\u66f4\u65b0\u5b83\u7684\u5185\u5b58\u3002\u6211\u4eec\u53ea\u9700\u8981\u66f4\u65b0\u8fd9\u4e2aUniform\u7f13\u51b2\u4e00\u6b21\uff0c\u6240\u6709\u4f7f\u7528\u8fd9\u4e2a\u7f13\u51b2\u7684\u7740\u8272\u5668\u5c31\u90fd\u4f7f\u7528\u7684\u662f\u66f4\u65b0\u540e\u7684\u6570\u636e\u4e86\u3002\u4f46\u662f\uff0c\u5982\u4f55\u624d\u80fd\u8ba9OpenGL\u77e5\u9053\u54ea\u4e2aUniform\u7f13\u51b2\u5bf9\u5e94\u7684\u662f\u54ea\u4e2aUniform\u5757\u5462\uff1f<\/p>\n\n\n\n
\u5728OpenGL\u4e0a\u4e0b\u6587\u4e2d\uff0c\u5b9a\u4e49\u4e86\u4e00\u4e9b\u7ed1\u5b9a\u70b9(Binding Point)\uff0c\u6211\u4eec\u53ef\u4ee5\u5c06\u4e00\u4e2aUniform\u7f13\u51b2\u94fe\u63a5\u81f3\u5b83\u3002\u5728\u521b\u5efaUniform\u7f13\u51b2\u4e4b\u540e\uff0c\u6211\u4eec\u5c06\u5b83\u7ed1\u5b9a\u5230\u5176\u4e2d\u4e00\u4e2a\u7ed1\u5b9a\u70b9\u4e0a\uff0c\u5e76\u5c06\u7740\u8272\u5668\u4e2d\u7684Uniform\u5757\u7ed1\u5b9a\u5230\u76f8\u540c\u7684\u7ed1\u5b9a\u70b9\uff0c\u628a\u5b83\u4eec\u8fde\u63a5\u5230\u4e00\u8d77\u3002\u4e0b\u9762\u7684\u8fd9\u4e2a\u56fe\u793a\u5c55\u793a\u4e86\u8fd9\u4e2a\uff1a<\/p>\n\n\n\n
\"\"\/<\/figure>\n\n\n\n
\u4f60\u53ef\u4ee5\u770b\u5230\uff0c\u6211\u4eec\u53ef\u4ee5\u7ed1\u5b9a\u591a\u4e2aUniform\u7f13\u51b2\u5230\u4e0d\u540c\u7684\u7ed1\u5b9a\u70b9\u4e0a\u3002\u56e0\u4e3a\u7740\u8272\u5668A\u548c\u7740\u8272\u5668B\u90fd\u6709\u4e00\u4e2a\u94fe\u63a5\u5230\u7ed1\u5b9a\u70b90\u7684Uniform\u5757\uff0c\u5b83\u4eec\u7684Uniform\u5757\u5c06\u4f1a\u5171\u4eab\u76f8\u540c\u7684uniform\u6570\u636e\uff0cuboMatrices\uff0c\u524d\u63d0\u6761\u4ef6\u662f\u4e24\u4e2a\u7740\u8272\u5668\u90fd\u5b9a\u4e49\u4e86\u76f8\u540c\u7684Matrices Uniform\u5757\u3002<\/p>\n\n\n\n
\u4e3a\u4e86\u5c06Uniform\u5757\u7ed1\u5b9a\u5230\u4e00\u4e2a\u7279\u5b9a\u7684\u7ed1\u5b9a\u70b9\u4e2d\uff0c\u6211\u4eec\u9700\u8981\u8c03\u7528glUniformBlockBinding\u51fd\u6570\uff0c\u5b83\u7684\u7b2c\u4e00\u4e2a\u53c2\u6570\u662f\u4e00\u4e2a\u7a0b\u5e8f\u5bf9\u8c61\uff0c\u4e4b\u540e\u662f\u4e00\u4e2aUniform\u5757\u7d22\u5f15\u548c\u94fe\u63a5\u5230\u7684\u7ed1\u5b9a\u70b9\u3002Uniform\u5757\u7d22\u5f15(Uniform Block Index)\u662f\u7740\u8272\u5668\u4e2d\u5df2\u5b9a\u4e49Uniform\u5757\u7684\u4f4d\u7f6e\u503c\u7d22\u5f15\u3002\u8fd9\u53ef\u4ee5\u901a\u8fc7\u8c03\u7528glGetUniformBlockIndex\u6765\u83b7\u53d6\uff0c\u5b83\u63a5\u53d7\u4e00\u4e2a\u7a0b\u5e8f\u5bf9\u8c61\u548cUniform\u5757\u7684\u540d\u79f0\u3002\u6211\u4eec\u53ef\u4ee5\u7528\u4ee5\u4e0b\u65b9\u5f0f\u5c06\u56fe\u793a\u4e2d\u7684Lights Uniform\u5757\u94fe\u63a5\u5230\u7ed1\u5b9a\u70b92\uff1a<\/p>\n\n\n\n
unsigned int lights_index = glGetUniformBlockIndex(shaderA.ID, \"Lights\");   \nglUniformBlockBinding(shaderA.ID, lights_index, 2);\n<\/code><\/pre>\n\n\n\n
\u6ce8\u610f\u6211\u4eec\u9700\u8981\u5bf9\u6bcf\u4e2a<\/strong>\u7740\u8272\u5668\u91cd\u590d\u8fd9\u4e00\u6b65\u9aa4\u3002<\/p>\n\n\n\n
\u4eceOpenGL 4.2\u7248\u672c\u8d77\uff0c\u4f60\u4e5f\u53ef\u4ee5\u6dfb\u52a0\u4e00\u4e2a\u5e03\u5c40\u6807\u8bc6\u7b26\uff0c\u663e\u5f0f\u5730\u5c06Uniform\u5757\u7684\u7ed1\u5b9a\u70b9\u50a8\u5b58\u5728\u7740\u8272\u5668\u4e2d\uff0c\u8fd9\u6837\u5c31\u4e0d\u7528\u518d\u8c03\u7528glGetUniformBlockIndex\u548cglUniformBlockBinding\u4e86\u3002\u4e0b\u9762\u7684\u4ee3\u7801\u663e\u5f0f\u5730\u8bbe\u7f6e\u4e86Lights Uniform\u5757\u7684\u7ed1\u5b9a\u70b9\u3002<\/p>\n\n\n\n
layout(std140, binding = 2) uniform Lights { ... };\n<\/code><\/pre>\n\n\n\n
\u63a5\u4e0b\u6765\uff0c\u6211\u4eec\u8fd8\u9700\u8981\u7ed1\u5b9aUniform\u7f13\u51b2\u5bf9\u8c61\u5230\u76f8\u540c\u7684\u7ed1\u5b9a\u70b9\u4e0a\uff0c\u8fd9\u53ef\u4ee5\u4f7f\u7528glBindBufferBase\u6216glBindBufferRange\u6765\u5b8c\u6210\u3002<\/p>\n\n\n\n
glBindBufferBase(GL_UNIFORM_BUFFER, 2, uboExampleBlock); \n\/\/ \u6216\nglBindBufferRange(GL_UNIFORM_BUFFER, 2, uboExampleBlock, 0, 152);\n<\/code><\/pre>\n\n\n\n
glBindbufferBase\u9700\u8981\u4e00\u4e2a\u76ee\u6807\uff0c\u4e00\u4e2a\u7ed1\u5b9a\u70b9\u7d22\u5f15\u548c\u4e00\u4e2aUniform\u7f13\u51b2\u5bf9\u8c61\u4f5c\u4e3a\u5b83\u7684\u53c2\u6570\u3002\u8fd9\u4e2a\u51fd\u6570\u5c06uboExampleBlock\u94fe\u63a5\u5230\u7ed1\u5b9a\u70b92\u4e0a\uff0c\u81ea\u6b64\uff0c\u7ed1\u5b9a\u70b9\u7684\u4e24\u7aef\u90fd\u94fe\u63a5\u4e0a\u4e86\u3002\u4f60\u4e5f\u53ef\u4ee5\u4f7f\u7528glBindBufferRange\u51fd\u6570\uff0c\u5b83\u9700\u8981\u4e00\u4e2a\u9644\u52a0\u7684\u504f\u79fb\u91cf\u548c\u5927\u5c0f\u53c2\u6570\uff0c\u8fd9\u6837\u5b50\u4f60\u53ef\u4ee5\u7ed1\u5b9aUniform\u7f13\u51b2\u7684\u7279\u5b9a\u4e00\u90e8\u5206\u5230\u7ed1\u5b9a\u70b9\u4e2d\u3002\u901a\u8fc7\u4f7f\u7528glBindBufferRange\u51fd\u6570\uff0c\u4f60\u53ef\u4ee5\u8ba9\u591a\u4e2a\u4e0d\u540c\u7684Uniform\u5757\u7ed1\u5b9a\u5230\u540c\u4e00\u4e2aUniform\u7f13\u51b2\u5bf9\u8c61\u4e0a\u3002<\/p>\n\n\n\n
\u73b0\u5728\uff0c\u6240\u6709\u7684\u4e1c\u897f\u90fd\u914d\u7f6e\u5b8c\u6bd5\u4e86\uff0c\u6211\u4eec\u53ef\u4ee5\u5f00\u59cb\u5411Uniform\u7f13\u51b2\u4e2d\u6dfb\u52a0\u6570\u636e\u4e86\u3002\u53ea\u8981\u6211\u4eec\u9700\u8981\uff0c\u5c31\u53ef\u4ee5\u4f7f\u7528glBufferSubData\u51fd\u6570\uff0c\u7528\u4e00\u4e2a\u5b57\u8282\u6570\u7ec4\u6dfb\u52a0\u6240\u6709\u7684\u6570\u636e\uff0c\u6216\u8005\u66f4\u65b0\u7f13\u51b2\u7684\u4e00\u90e8\u5206\u3002\u8981\u60f3\u66f4\u65b0uniform\u53d8\u91cfboolean\uff0c\u6211\u4eec\u53ef\u4ee5\u7528\u4ee5\u4e0b\u65b9\u5f0f\u66f4\u65b0Uniform\u7f13\u51b2\u5bf9\u8c61\uff1a<\/p>\n\n\n\n
glBindBuffer(GL_UNIFORM_BUFFER, uboExampleBlock);\nint b = true; \/\/ GLSL\u4e2d\u7684bool\u662f4\u5b57\u8282\u7684\uff0c\u6240\u4ee5\u6211\u4eec\u5c06\u5b83\u5b58\u4e3a\u4e00\u4e2ainteger\nglBufferSubData(GL_UNIFORM_BUFFER, 144, 4, &b); \nglBindBuffer(GL_UNIFORM_BUFFER, 0);\n<\/code><\/pre>\n\n\n\n
\u540c\u6837\u7684\u6b65\u9aa4\u4e5f\u80fd\u5e94\u7528\u5230Uniform\u5757\u4e2d\u5176\u5b83\u7684uniform\u53d8\u91cf\u4e0a\uff0c\u4f46\u9700\u8981\u4f7f\u7528\u4e0d\u540c\u7684\u8303\u56f4\u53c2\u6570\u3002<\/p>\n\n\n\n
\u4e00\u4e2a\u7b80\u5355\u7684\u4f8b\u5b50<\/h2>\n\n\n\n
\u6240\u4ee5\uff0c\u6211\u4eec\u6765\u5c55\u793a\u4e00\u4e2a\u771f\u6b63\u4f7f\u7528Uniform\u7f13\u51b2\u5bf9\u8c61\u7684\u4f8b\u5b50\u3002\u5982\u679c\u6211\u4eec\u56de\u5934\u770b\u770b\u4e4b\u524d\u6240\u6709\u7684\u4ee3\u7801\u4f8b\u5b50\uff0c\u6211\u4eec\u4e0d\u65ad\u5730\u5728\u4f7f\u75283\u4e2a\u77e9\u9635\uff1a\u6295\u5f71\u3001\u89c2\u5bdf\u548c\u6a21\u578b\u77e9\u9635\u3002\u5728\u6240\u6709\u7684\u8fd9\u4e9b\u77e9\u9635\u4e2d\uff0c\u53ea\u6709\u6a21\u578b\u77e9\u9635\u4f1a\u9891\u7e41\u53d8\u52a8\u3002\u5982\u679c\u6211\u4eec\u6709\u591a\u4e2a\u7740\u8272\u5668\u4f7f\u7528\u4e86\u8fd9\u540c\u4e00\u7ec4\u77e9\u9635\uff0c\u90a3\u4e48\u4f7f\u7528Uniform\u7f13\u51b2\u5bf9\u8c61\u53ef\u80fd\u4f1a\u66f4\u597d\u3002<\/p>\n\n\n\n
\u6211\u4eec\u4f1a\u5c06\u6295\u5f71\u548c\u6a21\u578b\u77e9\u9635\u5b58\u50a8\u5230\u4e00\u4e2a\u53eb\u505aMatrices\u7684Uniform\u5757\u4e2d\u3002\u6211\u4eec\u4e0d\u4f1a\u5c06\u6a21\u578b\u77e9\u9635\u5b58\u5728\u8fd9\u91cc\uff0c\u56e0\u4e3a\u6a21\u578b\u77e9\u9635\u5728\u4e0d\u540c\u7684\u7740\u8272\u5668\u4e2d\u4f1a\u4e0d\u65ad\u6539\u53d8\uff0c\u6240\u4ee5\u4f7f\u7528Uniform\u7f13\u51b2\u5bf9\u8c61\u5e76\u4e0d\u4f1a\u5e26\u6765\u4ec0\u4e48\u597d\u5904\u3002<\/p>\n\n\n\n
#version 330 core\nlayout (location = 0) in vec3 aPos;\n\nlayout (std140) uniform Matrices\n{\n    mat4 projection;\n    mat4 view;\n};\nuniform mat4 model;\n\nvoid main()\n{\n    gl_Position = projection * view * model * vec4(aPos, 1.0);\n}\n<\/code><\/pre>\n\n\n\n
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unsigned int uniformBlockIndexRed    = glGetUniformBlockIndex(shaderRed.ID, \"Matrices\");\nunsigned int uniformBlockIndexGreen  = glGetUniformBlockIndex(shaderGreen.ID, \"Matrices\");\nunsigned int uniformBlockIndexBlue   = glGetUniformBlockIndex(shaderBlue.ID, \"Matrices\");\nunsigned int uniformBlockIndexYellow = glGetUniformBlockIndex(shaderYellow.ID, \"Matrices\");  \n\nglUniformBlockBinding(shaderRed.ID,    uniformBlockIndexRed, 0);\nglUniformBlockBinding(shaderGreen.ID,  uniformBlockIndexGreen, 0);\nglUniformBlockBinding(shaderBlue.ID,   uniformBlockIndexBlue, 0);\nglUniformBlockBinding(shaderYellow.ID, uniformBlockIndexYellow, 0);\n<\/code><\/pre>\n\n\n\n
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unsigned int uboMatrices\nglGenBuffers(1, &uboMatrices);\n\nglBindBuffer(GL_UNIFORM_BUFFER, uboMatrices);\nglBufferData(GL_UNIFORM_BUFFER, 2 * sizeof(glm::mat4), NULL, GL_STATIC_DRAW);\nglBindBuffer(GL_UNIFORM_BUFFER, 0);\n\nglBindBufferRange(GL_UNIFORM_BUFFER, 0, uboMatrices, 0, 2 * sizeof(glm::mat4));\n<\/code><\/pre>\n\n\n\n
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glm::mat4 projection = glm::perspective(glm::radians(45.0f), (float)width\/(float)height, 0.1f, 100.0f);\nglBindBuffer(GL_UNIFORM_BUFFER, uboMatrices);\nglBufferSubData(GL_UNIFORM_BUFFER, 0, sizeof(glm::mat4), glm::value_ptr(projection));\nglBindBuffer(GL_UNIFORM_BUFFER, 0);\n<\/code><\/pre>\n\n\n\n
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glm::mat4 view = camera.GetViewMatrix();           \nglBindBuffer(GL_UNIFORM_BUFFER, uboMatrices);\nglBufferSubData(GL_UNIFORM_BUFFER, sizeof(glm::mat4), sizeof(glm::mat4), glm::value_ptr(view));\nglBindBuffer(GL_UNIFORM_BUFFER, 0);\n<\/code><\/pre>\n\n\n\n
Uniform\u7f13\u51b2\u5bf9\u8c61\u7684\u90e8\u5206\u5c31\u7ed3\u675f\u4e86\u3002\u6bcf\u4e2a\u5305\u542b\u4e86Matrices\u8fd9\u4e2aUniform\u5757\u7684\u9876\u70b9\u7740\u8272\u5668\u5c06\u4f1a\u5305\u542b\u50a8\u5b58\u5728uboMatrices\u4e2d\u7684\u6570\u636e\u3002\u6240\u4ee5\uff0c\u5982\u679c\u6211\u4eec\u73b0\u5728\u8981\u75284\u4e2a\u4e0d\u540c\u7684\u7740\u8272\u5668\u7ed8\u52364\u4e2a\u7acb\u65b9\u4f53\uff0c\u5b83\u4eec\u7684\u6295\u5f71\u548c\u89c2\u5bdf\u77e9\u9635\u90fd\u4f1a\u662f\u4e00\u6837\u7684\u3002<\/p>\n\n\n\n
glBindVertexArray(cubeVAO);\nshaderRed.use();\nglm::mat4 model;\nmodel = glm::translate(model, glm::vec3(-0.75f, 0.75f, 0.0f));  \/\/ \u79fb\u52a8\u5230\u5de6\u4e0a\u89d2\nshaderRed.setMat4(\"model\", model);\nglDrawArrays(GL_TRIANGLES, 0, 36);        \n\/\/ ... \u7ed8\u5236\u7eff\u8272\u7acb\u65b9\u4f53\n\/\/ ... \u7ed8\u5236\u84dd\u8272\u7acb\u65b9\u4f53\n\/\/ ... \u7ed8\u5236\u9ec4\u8272\u7acb\u65b9\u4f53 \n<\/code><\/pre>\n\n\n\n
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\"\"\/<\/figure>\n\n\n\n
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\u539f\u6587\uff1ahttps:\/\/learnopengl-cn.github.io\/04%20Advanced%20Ope […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"_links":{"self":[{"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/posts\/2353"}],"collection":[{"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2353"}],"version-history":[{"count":3,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/posts\/2353\/revisions"}],"predecessor-version":[{"id":2363,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/posts\/2353\/revisions\/2363"}],"wp:attachment":[{"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2353"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2353"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2353"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}