如何使用 OpenGL 将数据发送到顶点着色器?
How to send data to vertex shader with OpenGL?
我在向我的顶点着色器发送数据时遇到了一些问题:
#version 450 core
layout (location = 5) in vec3 in_Vertex;
layout (location = 6) in vec3 in_Color;
in int gl_InstanceID;
layout (location = 0) uniform mat4 projection;
layout (location = 1) uniform mat4 modelview;
layout (location = 2) uniform float posX;
layout (location = 3) uniform float posY;
layout (location = 4) uniform uint posZ;
out vec4 v_color;
void main()
{
float tmpX = posX;
float tmpY = posY;
uint tmpZ = posZ;
gl_Position = projection * modelview * vec4(in_Vertex.x + tmpX*2, in_Vertex.y + tmpY*2, in_Vertex.z + tmpZ, 1.0) + vec4(in_Color, 0.0);
v_color = vec4(in_Color,1.0);
}
in_Vertex 工作正常,但 in_Color 似乎有错误的值,我将数据发送为:
glUseProgram(m_shaderPerso.getID());
glBindBuffer(GL_ARRAY_BUFFER, m_vbo);
glVertexAttribPointer(5, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
glEnableVertexAttribArray(5);
glVertexAttribPointer(6, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(m_offsetColor));
glEnableVertexAttribArray(6);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_ibo);
glUniformMatrix4fv(0, 1, GL_FALSE, glm::value_ptr(projection));
glUniformMatrix4fv(1, 1, GL_FALSE, glm::value_ptr(modelview));
for( auto &x : m_mapPos)
{
glUniform1f(2, x.second.getX());
glUniform1f(3, x.second.getY());
glUniform1ui(4, s_map->getHauteur(x.second.getXint(),x.second.getYint()));
glDrawElements(GL_TRIANGLES, m_tailleI, GL_UNSIGNED_BYTE, 0);
}
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
glDisableVertexAttribArray(6);
glDisableVertexAttribArray(5);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glUseProgram(m_shaderPerso.getID());
然后我用 :
初始化 VBO
glGenBuffers(1, &m_vbo);
glBindBuffer(GL_ARRAY_BUFFER, m_vbo); //Verrouillage VBO
glBufferData(GL_ARRAY_BUFFER, (tailleV * sizeof(float)) + (m_tailleI*3 * sizeof(float)), 0, GL_STATIC_DRAW); //Allocation memoire
glBufferSubData(GL_ARRAY_BUFFER, 0, tailleV * sizeof(float), m_vertices); //Transfert données vertices
glBufferSubData(GL_ARRAY_BUFFER, tailleV * sizeof(float), m_tailleI*3 * sizeof(float), m_color); //Transfert données couleurs
glBindBuffer(GL_ARRAY_BUFFER, 0);
glGenBuffers(1, &m_ibo); //Generation IBO (indices)
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_ibo); //Verrouillage IBO
glBufferData(GL_ELEMENT_ARRAY_BUFFER, m_tailleI * sizeof(GLubyte), 0, GL_STATIC_DRAW); //Allocation memoire
glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, 0, m_tailleI * sizeof(GLubyte), m_indices); //Transfert données
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
我真的不知道我的错误在哪里,所以我给了你所有可能有用的代码。我知道数组 m_vertices、m_color 和 m_indices 已正确初始化,并且顶点已正确显示,因此顶点和索引的 VBO 在 VRAM 中很好。大概是我发数据的时候弄错了,找了2天也找不到,我觉得换个新面貌可以帮到我。
感谢阅读并可能提供帮助:)
除了@HolyBlackCat 说的,你还在混interleaved mode with batch mode。当您填充缓冲区时,您正在使用批处理模式:
glBindBuffer(GL_ARRAY_BUFFER, m_vbo); //Verrouillage VBO
glBufferData(GL_ARRAY_BUFFER, (tailleV * sizeof(float)) + (m_tailleI*3 * sizeof(float)), 0, GL_STATIC_DRAW); //Allocation memoire
glBufferSubData(GL_ARRAY_BUFFER, 0, tailleV * sizeof(float), m_vertices); //Transfert données vertices
glBufferSubData(GL_ARRAY_BUFFER, tailleV * sizeof(float), m_tailleI*3 * sizeof(float), m_color); //Transfert données couleurs
首先填充顶点,然后在缓冲区的末尾填充颜色属性。
但是当你使用缓冲区时,你是在交错模式下使用它*:
glVertexAttribPointer(5, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
glVertexAttribPointer(6, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(m_offsetColor));
选择一个并坚持下去。
*在 glVertexAttribPointer
函数中,stride
可能有一个不正确的值。
或许,您可以通过更改来解决您的问题:
glVertexAttribPointer(6, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(m_offsetColor))
至:
glVertexAttribPointer(6, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), BUFFER_OFFSET(tailleV * sizeof(float)))
我在向我的顶点着色器发送数据时遇到了一些问题:
#version 450 core
layout (location = 5) in vec3 in_Vertex;
layout (location = 6) in vec3 in_Color;
in int gl_InstanceID;
layout (location = 0) uniform mat4 projection;
layout (location = 1) uniform mat4 modelview;
layout (location = 2) uniform float posX;
layout (location = 3) uniform float posY;
layout (location = 4) uniform uint posZ;
out vec4 v_color;
void main()
{
float tmpX = posX;
float tmpY = posY;
uint tmpZ = posZ;
gl_Position = projection * modelview * vec4(in_Vertex.x + tmpX*2, in_Vertex.y + tmpY*2, in_Vertex.z + tmpZ, 1.0) + vec4(in_Color, 0.0);
v_color = vec4(in_Color,1.0);
}
in_Vertex 工作正常,但 in_Color 似乎有错误的值,我将数据发送为:
glUseProgram(m_shaderPerso.getID());
glBindBuffer(GL_ARRAY_BUFFER, m_vbo);
glVertexAttribPointer(5, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
glEnableVertexAttribArray(5);
glVertexAttribPointer(6, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(m_offsetColor));
glEnableVertexAttribArray(6);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_ibo);
glUniformMatrix4fv(0, 1, GL_FALSE, glm::value_ptr(projection));
glUniformMatrix4fv(1, 1, GL_FALSE, glm::value_ptr(modelview));
for( auto &x : m_mapPos)
{
glUniform1f(2, x.second.getX());
glUniform1f(3, x.second.getY());
glUniform1ui(4, s_map->getHauteur(x.second.getXint(),x.second.getYint()));
glDrawElements(GL_TRIANGLES, m_tailleI, GL_UNSIGNED_BYTE, 0);
}
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
glDisableVertexAttribArray(6);
glDisableVertexAttribArray(5);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glUseProgram(m_shaderPerso.getID());
然后我用 :
初始化 VBOglGenBuffers(1, &m_vbo);
glBindBuffer(GL_ARRAY_BUFFER, m_vbo); //Verrouillage VBO
glBufferData(GL_ARRAY_BUFFER, (tailleV * sizeof(float)) + (m_tailleI*3 * sizeof(float)), 0, GL_STATIC_DRAW); //Allocation memoire
glBufferSubData(GL_ARRAY_BUFFER, 0, tailleV * sizeof(float), m_vertices); //Transfert données vertices
glBufferSubData(GL_ARRAY_BUFFER, tailleV * sizeof(float), m_tailleI*3 * sizeof(float), m_color); //Transfert données couleurs
glBindBuffer(GL_ARRAY_BUFFER, 0);
glGenBuffers(1, &m_ibo); //Generation IBO (indices)
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_ibo); //Verrouillage IBO
glBufferData(GL_ELEMENT_ARRAY_BUFFER, m_tailleI * sizeof(GLubyte), 0, GL_STATIC_DRAW); //Allocation memoire
glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, 0, m_tailleI * sizeof(GLubyte), m_indices); //Transfert données
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
我真的不知道我的错误在哪里,所以我给了你所有可能有用的代码。我知道数组 m_vertices、m_color 和 m_indices 已正确初始化,并且顶点已正确显示,因此顶点和索引的 VBO 在 VRAM 中很好。大概是我发数据的时候弄错了,找了2天也找不到,我觉得换个新面貌可以帮到我。
感谢阅读并可能提供帮助:)
除了@HolyBlackCat 说的,你还在混interleaved mode with batch mode。当您填充缓冲区时,您正在使用批处理模式:
glBindBuffer(GL_ARRAY_BUFFER, m_vbo); //Verrouillage VBO
glBufferData(GL_ARRAY_BUFFER, (tailleV * sizeof(float)) + (m_tailleI*3 * sizeof(float)), 0, GL_STATIC_DRAW); //Allocation memoire
glBufferSubData(GL_ARRAY_BUFFER, 0, tailleV * sizeof(float), m_vertices); //Transfert données vertices
glBufferSubData(GL_ARRAY_BUFFER, tailleV * sizeof(float), m_tailleI*3 * sizeof(float), m_color); //Transfert données couleurs
首先填充顶点,然后在缓冲区的末尾填充颜色属性。
但是当你使用缓冲区时,你是在交错模式下使用它*:
glVertexAttribPointer(5, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
glVertexAttribPointer(6, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(m_offsetColor));
选择一个并坚持下去。
*在 glVertexAttribPointer
函数中,stride
可能有一个不正确的值。
或许,您可以通过更改来解决您的问题:
glVertexAttribPointer(6, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(m_offsetColor))
至:
glVertexAttribPointer(6, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), BUFFER_OFFSET(tailleV * sizeof(float)))