{"id":286,"date":"2019-02-27T16:27:22","date_gmt":"2019-02-27T08:27:22","guid":{"rendered":"https:\/\/www.caiqinyi.cn\/?p=286"},"modified":"2021-04-24T16:28:32","modified_gmt":"2021-04-24T08:28:32","slug":"perspective_divide","status":"publish","type":"post","link":"https:\/\/www.caiqinyi.cn\/index.php\/2019\/02\/27\/perspective_divide\/","title":{"rendered":"OpenGL\u7a76\u7adf\u662f\u5728\u4ec0\u4e48\u65f6\u5019\u6267\u884c\u900f\u89c6\u9664\u6cd5\u7684\uff1f"},"content":{"rendered":"<p><script type=\"text\/javascript\" async src=\"https:\/\/www.caiqinyi.cn\/wp-content\/MathJax\/MathJax.js?config=TeX-AMS_CHTML\">\n<\/script><br \/>\n<script type=\"text\/x-mathjax-config\">\n    MathJax.Hub.Config({\n        tex2jax: {inlineMath: [['$','$']]},\n        TeX: {equationNumbers: {autoNumber: [\"AMS\"], useLabelIds: true}},\n        \"HTML-CSS\": {linebreaks: {automatic: true}},\n        SVG: {linebreaks: {automatic: true}}\n    });\n<\/script><\/p>\n<p>\u5728\u5b66\u4e60\u51e0\u4f55\u7740\u8272\u5668\u65f6\u770b\u5176Shader\u4ee3\u7801, \u4ea7\u751f\u4e86\u4e00\u4e2a\u5c0f\u95ee\u9898.<\/p>\n<p><!--more--><\/p>\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"C++\" data-enlighter-theme=\"monokai\">\r\n#version 330 core\r\nlayout (triangles) in;\r\nlayout (line_strip, max_vertices = 6) out;\r\n\r\nin VS_OUT {\r\n    vec3 normal;\r\n} gs_in[];\r\n\r\nconst float MAGNITUDE = 0.2;\r\n\r\nvoid GenerateLine(int index)\r\n{\r\n    gl_Position = gl_in[index].gl_Position;\r\n    EmitVertex();\r\n    gl_Position = gl_in[index].gl_Position + vec4(gs_in[index].normal, 0.0) * MAGNITUDE;\r\n    EmitVertex();\r\n    EndPrimitive();\r\n}\r\n\r\nvoid main()\r\n{\r\n    GenerateLine(0); \/\/ first vertex normal\r\n    GenerateLine(1); \/\/ second vertex normal\r\n    GenerateLine(2); \/\/ third vertex normal\r\n}\r\n<\/pre>\n<p>\u6b64\u5904\u7684gl_in[index].gl_Position\u662f\u5728\u524d\u9762\u7684\u9876\u70b9\u7740\u8272\u5668\u4e2d\u7ecf\u8fc7MVP\u77e9\u9635\u7684(\u5373\u5904\u4e8e\u88c1\u526a\u7a7a\u95f4\u4e0b), \u800cgs_in[index].normal\u5219\u4e5f\u662f\u7ecf\u8fc7\u4e86\u6295\u5f71\u77e9\u9635\u548c\u6cd5\u7ebf\u77e9\u9635\u7684\u5904\u7406(\u4ea6\u5904\u4e8e\u88c1\u526a\u7a7a\u95f4\u4e4b\u4e0b). \u800c\u6211\u4eec\u77e5\u9053, \u5728\u9876\u70b9\u7740\u8272\u5668\u4e4b\u540eOpenGL\u4f1a\u81ea\u52a8\u6267\u884c\u900f\u89c6\u9664\u6cd5, \u4f46\u7a76\u7adf\u662f\u5426\u662f\u7acb\u5373\u6267\u884c, \u8bb8\u591a\u56fd\u5185\u535a\u5ba2\u57fa\u672c\u90fd\u6ca1\u63d0\u5230. \u5982\u679c\u5728\u8fd0\u884c\u51e0\u4f55\u7740\u8272\u5668\u65f6\u5df2\u7ecf\u6267\u884c\u4e86\u900f\u89c6\u9664\u6cd5, \u90a3\u4e48\u6b64\u65f6\u5c06\u9876\u70b9\u4f4d\u7f6e\u548c\u6cd5\u5411\u91cf\u76f4\u63a5\u76f8\u52a0\u662f\u4e0d\u5408\u7406\u7684, \u56e0\u4e3a\u524d\u8005\u5df2\u7ecf\u9664\u8fc7\u4e86$w$\u5206\u91cf\u4e14\u7ecf\u8fc7\u4e86\u89c6\u53e3\u53d8\u6362.<\/p>\n<p>\u7ecf\u8fc7\u548c\u5e08\u5144\u7684\u8ba8\u8bba, \u4e14\u5728Google\u4e0a\u641c\u5f97\u76f8\u5173\u95ee\u9898, \u7ec8\u4e8e\u89e3\u51b3\u4e86\u8fd9\u4e2a\u5c0f\u5c0f\u7684\u95ee\u9898. <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.caiqinyi.cn\/wp-content\/uploads\/2019\/02\/01.jpg\" alt=\"\" width=\"28\" height=\"29\" class=\"alignnone size-full wp-image-288\" \/><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.caiqinyi.cn\/wp-content\/uploads\/2019\/02\/TIM\u622a\u56fe20190227162645.jpg\" alt=\"\" width=\"744\" height=\"251\" class=\"alignnone size-full wp-image-289\" srcset=\"https:\/\/www.caiqinyi.cn\/wp-content\/uploads\/2019\/02\/TIM\u622a\u56fe20190227162645.jpg 744w, https:\/\/www.caiqinyi.cn\/wp-content\/uploads\/2019\/02\/TIM\u622a\u56fe20190227162645-300x101.jpg 300w\" sizes=\"(max-width: 744px) 100vw, 744px\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5728\u5b66\u4e60\u51e0\u4f55\u7740\u8272\u5668\u65f6\u770b\u5176Shader\u4ee3\u7801, \u4ea7\u751f\u4e86\u4e00\u4e2a\u5c0f\u95ee\u9898.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[],"_links":{"self":[{"href":"https:\/\/www.caiqinyi.cn\/index.php\/wp-json\/wp\/v2\/posts\/286"}],"collection":[{"href":"https:\/\/www.caiqinyi.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.caiqinyi.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.caiqinyi.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.caiqinyi.cn\/index.php\/wp-json\/wp\/v2\/comments?post=286"}],"version-history":[{"count":4,"href":"https:\/\/www.caiqinyi.cn\/index.php\/wp-json\/wp\/v2\/posts\/286\/revisions"}],"predecessor-version":[{"id":772,"href":"https:\/\/www.caiqinyi.cn\/index.php\/wp-json\/wp\/v2\/posts\/286\/revisions\/772"}],"wp:attachment":[{"href":"https:\/\/www.caiqinyi.cn\/index.php\/wp-json\/wp\/v2\/media?parent=286"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.caiqinyi.cn\/index.php\/wp-json\/wp\/v2\/categories?post=286"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.caiqinyi.cn\/index.php\/wp-json\/wp\/v2\/tags?post=286"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}