Question

我无法在我的立方体上设置纹理：它呈现灰色。我在Ubuntu上使用Qt 5.1和QTCreator，使用OpenGL 3.3。

以下是我的着色器：

#version 330
layout(location = 0) in vec3 position;
layout(location = 1) in vec2 Texc;

uniform sampler2D tex ;
uniform mat4 modelToWorld;
uniform mat4 worldToCamera;
uniform mat4 cameraToView;
out vec4 vColor;
void main()
{
gl_Position = cameraToView * worldToCamera * modelToWorld *  vec4(position, 1.0);
vColor = texture2D(tex, Texc);
}

#version 330
in vec4 vColor;
out vec4 fColor;

void main()
{
fColor = vColor; 
}

这是window.cpp文件，其中包含有用的功能：

void Window::initializeGL()
{
// Initialize OpenGL Backend
initializeOpenGLFunctions();
connect(this, SIGNAL(frameSwapped()), this, SLOT(update()));
printContextInformation();

// Set global information
glEnable(GL_CULL_FACE);
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);

// Application-specific initialization
{
    // Create Shader (Do not release until VAO is created)
    m_program = new QOpenGLShaderProgram();
    m_program->addShaderFromSourceFile(QOpenGLShader::Vertex, ":/vertexText.txt");
    m_program->addShaderFromSourceFile(QOpenGLShader::Fragment, ":/fragmentText.txt");
    m_program->link();
    m_program->bind();

    QOpenGLTexture *texture = new QOpenGLTexture(QImage(":/texture.jpg").mirrored());
    //texture->setMinificationFilter(QOpenGLTexture::LinearMipMapLinear);
    texture->setMagnificationFilter(QOpenGLTexture::Linear);
    texture->bind() ;

    u_texturecolors = m_program->uniformLocation("tex");

    // Cache Uniform Locations
    u_modelToWorld = m_program->uniformLocation("modelToWorld");
    u_worldToCamera = m_program->uniformLocation("worldToCamera");
    u_cameraToView = m_program->uniformLocation("cameraToView");
    //u_worldToView = m_program->uniformLocation("worldToView");

    // Create Buffer (Do not release until VAO is created)
    m_vertex.create();
    m_vertex.bind();
    m_vertex.setUsagePattern(QOpenGLBuffer::StaticDraw);
    m_vertex.allocate(sg_vertexes, sizeof(sg_vertexes));

    // Create Vertex Array Object
    m_object.create();
    m_object.bind();
    m_program->enableAttributeArray(0);
    m_program->enableAttributeArray(1);
    m_program->setAttributeBuffer(0, GL_FLOAT, Vertex::positionOffset(), Vertex::PositionTupleSize, Vertex::stride());
    m_program->setAttributeBuffer(1, GL_FLOAT, Vertex::texcoordOffset(), Vertex::TexcoordTupleSize, Vertex::stride());

    // Release (unbind) all
    m_object.release();
    m_vertex.release();
    m_program->release();

    m_transform.setDataMove();
}
}

void Window::paintGL()
{
// Clear
glClear(GL_COLOR_BUFFER_BIT);

// Render using our shader
m_program->bind();
m_program->setUniformValue(u_texturecolors, m_texturecolors);
m_program->setUniformValue(u_worldToCamera, m_camera.toMatrix());
m_program->setUniformValue(u_cameraToView, m_projection);
//m_program->setUniformValue(u_worldToView, m_projection);
{
    m_object.bind();
    m_program->setUniformValue(u_modelToWorld, m_transform.toMatrix());
    glDrawArrays(GL_TRIANGLES, 0, sizeof(sg_vertexes) / sizeof(sg_vertexes[0]));
    m_object.release();
}
m_program->release();
}

关联的window.h标题：

class Window : public QOpenGLWindow,
           protected QOpenGLFunctions
 {
 Q_OBJECT

 // OpenGL Events
 public:

  Window();
 ~Window();

 void initializeGL();
 void resizeGL(int width, int height);
 void paintGL();
 void teardownGL();

 public slots:
 void update() ;

 protected:
 void keyPressEvent(QKeyEvent *event);
 void keyReleaseEvent(QKeyEvent *event);
 void mousePressEvent(QMouseEvent *event);
 void mouseReleaseEvent(QMouseEvent *event);

 private:
 // OpenGL State Information
 QOpenGLBuffer m_vertex;
 QOpenGLVertexArrayObject m_object;
 QOpenGLShaderProgram *m_program;

// Shader Information
int u_modelToWorld;
int u_worldToCamera;
int u_cameraToView;
int u_texturecolors ;
QVector3D m_texturecolors ;
Camera3D m_camera;
QMatrix4x4 m_projection;
Transform3D m_transform;
};

最后是顶点标题：

class Vertex
{
public:
// Constructors
Q_DECL_CONSTEXPR Vertex();
Q_DECL_CONSTEXPR explicit Vertex(const QVector3D &position);
Q_DECL_CONSTEXPR Vertex(const QVector3D &position, const QVector3D &color);
Q_DECL_CONSTEXPR Vertex(const QVector3D &position, const QVector2D &texcoord);

// Accessors / Mutators
Q_DECL_CONSTEXPR const QVector3D& position() const;
Q_DECL_CONSTEXPR const QVector3D& color() const;
Q_DECL_CONSTEXPR const QVector2D& texcoord() const;

void setPosition(const QVector3D& position);
void setColor(const QVector3D& color);
void setTexcoord(const QVector2D& texcoord);


// OpenGL Helpers
static const int PositionTupleSize = 3;
static const int ColorTupleSize = 3;
static const int TexcoordTupleSize = 2 ;
static Q_DECL_CONSTEXPR int positionOffset();
static Q_DECL_CONSTEXPR int colorOffset();
static Q_DECL_CONSTEXPR int texcoordOffset();
static Q_DECL_CONSTEXPR int stride();

private:
QVector3D m_position;
QVector3D m_color;
QVector2D m_texcoord ;
};

Q_DECLARE_TYPEINFO(Vertex, Q_MOVABLE_TYPE);

// Constructors
Q_DECL_CONSTEXPR inline Vertex::Vertex() {}
Q_DECL_CONSTEXPR inline Vertex::Vertex(const QVector3D &position) :  m_position(position) {}
Q_DECL_CONSTEXPR inline Vertex::Vertex(const QVector3D &position, const QVector3D &color) : m_position(position), m_color(color) {}
Q_DECL_CONSTEXPR inline Vertex::Vertex(const QVector3D &position, const QVector2D &texcoord) : m_position(position), m_texcoord(texcoord) {}

// Accessors / Mutators
Q_DECL_CONSTEXPR inline const QVector3D& Vertex::position() const { return m_position; }
Q_DECL_CONSTEXPR inline const QVector3D& Vertex::color() const { return m_color; }
Q_DECL_CONSTEXPR inline const QVector2D& Vertex::texcoord() const { return m_texcoord; }

void inline Vertex::setPosition(const QVector3D& position) { m_position = position; }
void inline Vertex::setColor(const QVector3D& color) { m_color = color; }
void inline Vertex::setTexcoord(const QVector2D& texcoord) { m_texcoord = texcoord; }

// OpenGL Helpers
Q_DECL_CONSTEXPR inline int Vertex::positionOffset() { return offsetof(Vertex, m_position); }
Q_DECL_CONSTEXPR inline int Vertex::colorOffset() { return offsetof(Vertex, m_color); }
Q_DECL_CONSTEXPR inline int Vertex::texcoordOffset() { return offsetof(Vertex, m_texcoord); }

Q_DECL_CONSTEXPR inline int Vertex::stride() { return sizeof(Vertex); }

#endif // VERTEX_HSR

Answer 1

您正尝试在顶点着色器中应用纹理。相反，您应该在片段着色器中应用它。通过删除纹理并提供纹理坐标来修改顶点着色器：

out vec2 TexCoord;
void main()
{
// Removed this line: vColor = texture2D(tex, Texc);
    TexCoord = Texc;
}

修改片段着色器以像在顶点着色器中一样读取纹理：

in vec2 TexCoord;
void main()
{
    fColor = texture2D(tex, TexCoord); 
}

Qt OpenGL 3.3：纹理渲染问题

1 个答案: