使用GLM在OpenGL中绘制2个立方体 [英] Draw 2 cubes in OpenGL using GLM
问题描述
因此，我可以使用OpenGL3.2 +绘制旋转的多维数据集，并将其从0,0,0移到左侧，但是当我尝试绘制第二个多维数据集(向右)时，它不会呈现...
So I can draw a spinning cube using OpenGL3.2+ and translate it away from the 0,0,0 and to the left, but when I try and draw a second one (towards the right), it doesn't render...
这是我的显示功能:
void display()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glUseProgram(myShader.handle());
GLuint matLocation = glGetUniformLocation(myShader.handle(), "ProjectionMatrix");
glUniformMatrix4fv(matLocation, 1, GL_FALSE, &ProjectionMatrix[0][0]);
spinY+=0.03;
if(spinY>360) spinY = 0;
glm::mat4 viewMatrix;
viewMatrix = glm::translate(glm::mat4(1.0),glm::vec3(0,0,-100)); //viewing matrix
ModelViewMatrix = glm::translate(viewMatrix,glm::vec3(-30,0,0)); //translate object from the origin
ModelViewMatrix = glm::rotate(ModelViewMatrix,spinY, glm::vec3(0,1,0)); //rotate object about y axis
glUniformMatrix4fv(glGetUniformLocation(myShader.handle(), "ModelViewMatrix"), 1, GL_FALSE, &ModelViewMatrix[0][0]); //pass matrix to shader
//Add the following line just before the line to draw the cube to
//check that the origin of the cube in eye space is (-30, 0, -100);
result = glm::vec3(ModelViewMatrix * glm::vec4(0,0,0,1));
std::cout<<glm::to_string(result)<<std::endl; //print matrix to get coordinates.
myCube.render();
glUseProgram(0);
}
我希望能够使用相同的Cube类/大小等，但是只需再次渲染即可(我认为这是最有效/最佳的方法).
I want to be able to use the same Cube class / size etc, but just render it again (I assume that's the most efficient / best way to do it).
我尝试过
void display()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glUseProgram(myShader.handle());
GLuint matLocation = glGetUniformLocation(myShader.handle(), "ProjectionMatrix");
glUniformMatrix4fv(matLocation, 1, GL_FALSE, &ProjectionMatrix[0][0]);
spinY+=0.03;
if(spinY>360) spinY = 0;
glm::mat4 viewMatrix;
viewMatrix = glm::translate(glm::mat4(1.0),glm::vec3(0,0,-100)); //viewing matrix
ModelViewMatrix = glm::translate(viewMatrix,glm::vec3(-30,0,0)); //translate object from the origin
ModelViewMatrix = glm::rotate(ModelViewMatrix,spinY, glm::vec3(0,1,0)); //rotate object about y axis
glUniformMatrix4fv(glGetUniformLocation(myShader.handle(), "ModelViewMatrix"), 1, GL_FALSE, &ModelViewMatrix[0][0]); //pass matrix to shader
//Add the following line just before the line to draw the cube to
//check that the origin of the cube in eye space is (-30, 0, -100);
result = glm::vec3(ModelViewMatrix * glm::vec4(0,0,0,1));
std::cout<<glm::to_string(result)<<std::endl; //print matrix to get coordinates.
myCube.render();
glm::mat4 viewMatrix_TWO;
viewMatrix_TWO = glm::translate(glm::mat4(1.0),glm::vec3(0,0,-100)); //viewing matrix
ModelViewMatrix_TWO = glm::translate(viewMatrix_TWO,glm::vec3(30,0,0)); //translate object from the origin
ModelViewMatrix_TWO = glm::rotate(ModelViewMatrix_TWO,spinY, glm::vec3(0,1,0)); //rotate object about y axis
glUniformMatrix4fv(glGetUniformLocation(myShader.handle(), "ModelViewMatrix_TWO"), 1, GL_FALSE, &ModelViewMatrix[0][0]); //pass matrix to shader
myCube.render();
glUseProgram(0);
}
很明显，我实现错误了……如何在屏幕的任一侧获得一个多维数据集?谢谢.
Obviously, I've implemented it wrong... How can I get a cube either side of the screen? Thanks.
更新
我意识到，我还没有创建第二个多维数据集对象，但是现在实现了，它仍然无法正常工作……我是否会混淆视图/模型矩阵的交互方式?我为每个对象创建了一个新对象....
I realised, I hadn't created a second cube object, but with that now implemented, it still doesn't work... Am I confusing how the view/model matrices interact? I've created a new one for each object....
新代码:
myCube.render();
spinX+=0.03;
if(spinX>360) spinX = 0;
glm::mat4 viewMatrix_Two,ModelViewMatrix_Two;
viewMatrix_Two = glm::translate(glm::mat4(1.0),glm::vec3(0,0,-100)); //viewing matrix
ModelViewMatrix_Two = glm::translate(viewMatrix_Two,glm::vec3(30,0,0)); //translate object from the origin
ModelViewMatrix_Two = glm::rotate(ModelViewMatrix_Two,spinX, glm::vec3(0,1,0)); //rotate object about y axis
glUniformMatrix4fv(glGetUniformLocation(myShader.handle(), "ModelViewMatrix_Two"), 1, GL_FALSE, &ModelViewMatrix_Two[0][0]); //pass matrix to shader
myCube_Two.render();
更新
着色器:
uniform mat4 ModelViewMatrix;
//uniform mat4 ModelViewMatrix_Two; //NOT NEEDED - USED SAME SHADER OBJECT
uniform mat4 ProjectionMatrix;
in vec3 in_Position; // Position coming in
in vec3 in_Color; // colour coming in
out vec3 ex_Color; // colour leaving the vertex, this will be sent to the fragment shader
void main(void)
{
gl_Position = ProjectionMatrix * ModelViewMatrix * vec4(in_Position, 1.0);
//gl_Position = ProjectionMatrix * ModelViewMatrix_Two * vec4(in_Position, 1.0);
ex_Color = in_Color;
}
推荐答案
最后，我创建了第二个Cube对象，第二个查看矩阵，并将它们与着色器中已经建立的模型矩阵一起使用，似乎两个多维数据集都被调用/渲染
In the end, I created a second Cube object, second viewing matrix and used them with the already established model matrix in my shader seems both cubes are called/rendered individually.
正确的代码是:
glm::mat4 viewMatrix_Two, ModelViewMatrix_Two;
viewMatrix_Two = glm::translate(glm::mat4(1.0),glm::vec3(0,0,-200));
ModelViewMatrix = glm::translate(viewMatrix_Two,glm::vec3(30,0,0));
ModelViewMatrix = glm::rotate(ModelViewMatrix,spinX, glm::vec3(1,0,0));
glUniformMatrix4fv(glGetUniformLocation(myShader.handle(), "ModelViewMatrix"), 1, GL_FALSE, &ModelViewMatrix[0][0]); //pass matrix to shader
myCube_Two.render();
这篇关于使用GLM在OpenGL中绘制2个立方体的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
