Vertex Buffer: Buffer/data in Video RAM that defines triangle, we put data into GPU's VRAM, and issue drawcall (where to read from, how to read & interpret) Vertex Attribute Layout: What is in mem, how is it layout? (Ex. Vertex Position, Color, texture Coord, Normal, etc.) Index ...
Target参数是GL_PIXEL_PACK_BUFFER_ARB 或GL_PIXEL_UNPACK_BUFFER_ARB。第二个参数,指定映射的缓冲区的访问方式:从PBO中读数据(GL_READ_ONLY_ARB),写数据到PBO中(GL_WRITE_ONLY_ARB) 或读写PBO(GL_READ_WRITE_ARB)。 注意如果GPU仍使用此缓冲区对象,glMapBufferARB()不会返回,直到GPU完成了对相应缓冲区对...
To resolve this, OpenGL provides the GL_COPY_READ_BUFFER and GL_COPY_WRITE_BUFFER targets. These targets were added specifically to allow you to copy data from one buffer to another without any unintended side effects. Because they are not used for anything else in OpenGL, you can bind your...
另外该函数对于使用双缓存机制的OpenGL环境,默认的是读取后台缓存区数据,可以通过调用如下函数来使其读取前台缓存区,其参数为GL_FRONT、GL_BACK等。 voidglReadBuffer(GLenum mode); 1.1.3 包装的像素格式 上一节中函数glReadPixels的参数type,通常使用的是GL_FLOAT等类型,但是也提供例如GL_UNSIGNED_BYTE_3_2_2等...
GL_DYNAMIC_READ:OpenGL输出经常更新其内容,代码经常查询。 GL_DYNAMIC_COPY:OpenGL输出经常更新其内容,用于绘制或者用于拷贝至图片,使用频率高。 生成缓存的代码如下: // The type used for names in OpenGL is GLuintGLuint buffer;// Generate a name for the buffer, 此处第一个参数为生成缓存个数,可以一次...
glBindFramebuffer(GL_FRAMEBUFFER,depthMapFBO);glFramebufferTexture(GL_FRAMEBUFFER,GL_DEPTH_ATTACHMENT,depthCubemap,0);glDrawBuffer(GL_NONE);glReadBuffer(GL_NONE);glBindFramebuffer(GL_FRAMEBUFFER,0); 2.2 生成6个方向的相机 todo:这里有点不理解,按照右手定则,坐标是错的,后面有时间在深入研究,这里耽搁...
25.glReadBuffer,glDrawBuffer,glCopyPixels 其它注意事项: 1.glDrawArrays等函数中数据必须紧密排列,即间隔为0 2.各种数据的堆栈深度较低 参考代码: 1#ifndef WIDGET_H2#defineWIDGET_H34#include <QOpenGLWidget>5#include <QOpenGLFunctions>6#include <QOpenGLShaderProgram>78//QOpenGLFunctions类提供了跨平台访...
GlMapInvalidateBufferBit (繼承來源 GLES30) GlMapInvalidateRangeBit (繼承來源 GLES30) GlMapReadBit (繼承來源 GLES30) GlMapUnsynchronizedBit (繼承來源 GLES30) GlMapWriteBit (繼承來源 GLES30) GlMatrixStride GlMax (繼承來源 GLES30) GlMax3dTextureSize (繼承來源 GLES30) GlMaxArrayTextur...
// Read file's buffer contents into streams vShaderStream << vShaderFile.rdbuf(); fShaderStream << fShaderFile.rdbuf(); // close file handlers vShaderFile.close(); fShaderFile.close(); // Convert stream into string vertexCode = vShaderStream.str(); ...
GL_MAP_READ_BIT: Tells OpenGL we wish to read from the buffer. GL_MAP_WRITE_BIT: Lets OpenGL know we're gonna write to it, if you don't specify this anything could happen. If we don't use these flags for the storage creation GL will reject your mapping request with scorn. What'...