C++ (Qt) glGenVertexArrays(1, &vao); glBindVertexArray(vao); ..... glGenBuffers(1, &buffer); glBindBuffer(GL_ARRAY_BUFFER, buffer); glBufferData(GL_ARRAY_BUFFER, sizeof(vertex_positions), vertex_positions, GL_STATIC_DRAW); glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, NULL); glEnableVertexAttribArray(0);
C++ (Qt) QOpenGLVertexArrayObject* vao = new QOpenGLVertexArrayObject(this); vao->create(); vao->bind(); QOpenGLBuffer* buffer = new QOpenGLBuffer; buffer->create(); buffer->bind(); buffer->setUsagePattern(QOpenGLBuffer::StaticDraw); buffer->allocate(vertex_positions, sizeof(vertex_positions)); program->setAttributeBuffer(0, GL_FLOAT, 0, 3); program->enableAttributeArray(0);
C++ (Qt)#include "spinnycube.h"#include <QOpenGLShader>#include <QOpenGLBuffer>#include <QMatrix4x4>#include <QDebug>#include <QTime>#include <math.h> SpinnyCube::SpinnyCube(QWidget *parent) : QGLWidget(parent){ setWindowTitle("Spinny Cube"); proj_matrix = new QMatrix4x4; program = new QOpenGLShaderProgram; time = new QTime; many = false; time->start(); startTimer(16);}SpinnyCube::~SpinnyCube(){ delete proj_matrix; delete time;} void SpinnyCube::initializeGL(){ glClearColor(0.0f, 0.25f, 0.0f, 1.0f); glClearDepth(1.0f); const char * vs_source = { "#version 410 core \n" " \n" "in vec4 position; \n" " \n" "out VS_OUT \n" "{ \n" " vec4 color; \n" "} vs_out; \n" " \n" "uniform mat4 mv_matrix; \n" "uniform mat4 proj_matrix; \n" " \n" "void main(void) \n" "{ \n" " gl_Position = proj_matrix * mv_matrix * position; \n" " vs_out.color = position * 2.0 + vec4(0.5, 0.5, 0.5, 0.0); \n" "} \n" }; const char * fs_source = { "#version 410 core \n" " \n" "out vec4 color; \n" " \n" "in VS_OUT \n" "{ \n" " vec4 color; \n" "} fs_in; \n" " \n" "void main(void) \n" "{ \n" " color = fs_in.color; \n" "} \n" }; program->addShaderFromSourceCode(QOpenGLShader::Fragment, fs_source); program->addShaderFromSourceCode(QOpenGLShader::Vertex, vs_source); program->link(); mv_location = program->uniformLocation("mv_matrix"); proj_location = program->uniformLocation("proj_matrix"); // QOpenGLVertexArrayObject* vao = new QOpenGLVertexArrayObject(this);// vao->bind(); static const GLfloat vertex_positions[] = { -0.25f, 0.25f, -0.25f, -0.25f, -0.25f, -0.25f, 0.25f, -0.25f, -0.25f, 0.25f, -0.25f, -0.25f, 0.25f, 0.25f, -0.25f, -0.25f, 0.25f, -0.25f, 0.25f, -0.25f, -0.25f, 0.25f, -0.25f, 0.25f, 0.25f, 0.25f, -0.25f, 0.25f, -0.25f, 0.25f, 0.25f, 0.25f, 0.25f, 0.25f, 0.25f, -0.25f, 0.25f, -0.25f, 0.25f, -0.25f, -0.25f, 0.25f, 0.25f, 0.25f, 0.25f, -0.25f, -0.25f, 0.25f, -0.25f, 0.25f, 0.25f, 0.25f, 0.25f, 0.25f, -0.25f, -0.25f, 0.25f, -0.25f, -0.25f, -0.25f, -0.25f, 0.25f, 0.25f, -0.25f, -0.25f, -0.25f, -0.25f, 0.25f, -0.25f, -0.25f, 0.25f, 0.25f, -0.25f, -0.25f, 0.25f, 0.25f, -0.25f, 0.25f, 0.25f, -0.25f, -0.25f, 0.25f, -0.25f, -0.25f, -0.25f, -0.25f, -0.25f, -0.25f, -0.25f, 0.25f, -0.25f, 0.25f, -0.25f, 0.25f, 0.25f, -0.25f, 0.25f, 0.25f, 0.25f, 0.25f, 0.25f, 0.25f, -0.25f, 0.25f, 0.25f, -0.25f, 0.25f, -0.25f }; QOpenGLBuffer* buffer = new QOpenGLBuffer; buffer->create(); buffer->bind(); buffer->allocate(vertex_positions, sizeof(vertex_positions)); buffer->setUsagePattern(QOpenGLBuffer::StaticDraw); program->setAttributeArray(0, GL_FLOAT, NULL, 3); program->enableAttributeArray(0); glEnable(GL_CULL_FACE); glFrontFace(GL_CW); glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LEQUAL); } void SpinnyCube::paintGL(){ float currentTime = time->elapsed() / 1000.0f; glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); program->bind(); program->setUniformValue(proj_location, *proj_matrix); if (many) { int i; for (i = 0; i < 24; i++) { float f = i + currentTime * 0.3f; QMatrix4x4 mv_matrix; mv_matrix.translate(0.0f, 0.0f, -6.0f); mv_matrix.rotate(currentTime * 45.0f, 0.0f, 1.0f, 0.0f); mv_matrix.rotate(currentTime * 21.0f, 1.0f, 0.0f, 0.0f); mv_matrix.translate(sinf(2.1f * f) * 2.0f, cosf(1.7f * f) * 2.0f, sinf(1.3f * f) * cosf(1.5f * f) * 2.0f); program->setUniformValue(mv_location, mv_matrix); glDrawArrays(GL_TRIANGLES, 0, 36); } } else { float f = currentTime * 0.3f; QMatrix4x4 mv_matrix; mv_matrix.translate(0.0f, 0.0f, -4.0f); mv_matrix.translate(sinf(2.1f * f) * 0.5f, cosf(1.7f * f) * 0.5f, sinf(1.3f * f) * cosf(1.5f * f) * 2.0f); mv_matrix.rotate(currentTime * 45.0f, 0.0f, 1.0f, 0.0f); mv_matrix.rotate(currentTime * 81.0f, 1.0f, 0.0f, 0.0f); program->setUniformValue(mv_location, mv_matrix); glDrawArrays(GL_TRIANGLES, 0, 36); }} void SpinnyCube::resizeGL(int w, int h){ glViewport(0, 0, w, h); float aspect = static_cast<float>(w) / static_cast<float>(h); proj_matrix->setToIdentity(); proj_matrix->perspective(50.0f, aspect, 0.1f, 1000.0f);} void SpinnyCube::timerEvent(QTimerEvent *){ if (time->elapsed() % 4000 < 2000) many = false; else many = true; updateGL();}
C++ (Qt)gl_Position = proj_matrix * mv_matrix * position;
C++ (Qt) glGenBuffers(1, &buffer); glBindBuffer(GL_ARRAY_BUFFER, buffer); glBufferData(GL_ARRAY_BUFFER, sizeof(vertex_positions), vertex_positions, GL_STATIC_DRAW); glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, NULL);
C++ (Qt)int loc = program->attributeLocation("posAttr");
C++ (Qt)void QGLShaderProgram::setAttributeBuffer ( int location, GLenum type, int offset, int tupleSize, int stride = 0 )
