我已经创建了阴影贴图。但是它有两个问题: 1. 只有当我改变模型矩阵时,阴影才会出现。即最初没有阴影,但是当我按一个键移动图形时,即模型矩阵发生了变化,阴影出现了。2. 帧缓冲区上的纹理上有一条旧渲染的痕迹,导致拖尾很长。
任何人都可以对此有所了解吗?
这是问题的截图
在此处编辑代码:
void generateShadowTex()
{
//Calculate final ligting properties
glm::vec4 a_f=light_ambient*mat_ambient;
glm::vec4 d_f=light_diffuse*mat_diffuse;
glm::vec4 s_f=light_specular*mat_specular;
int counter=0;
glClear(GL_DEPTH_BUFFER_BIT);
glEnable(GL_DEPTH_TEST); // need depth test to correctly draw 3D objects
glClearColor(0,0,0,1);
//glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
if(wframe)
glPolygonMode(GL_FRONT_AND_BACK,GL_LINE);
else
glPolygonMode(GL_FRONT_AND_BACK,GL_FILL);
glActiveTexture(GL_TEXTURE3);
glBindTexture(GL_TEXTURE_2D,depthTex);
// MAths here for mvp manupulation
//Draw Elements
if(a<17 || a==18)
glDrawElements(GL_QUADS, masterNumberIndices[a], GL_UNSIGNED_INT, (char*) NULL+0);
else
glDrawElements(GL_TRIANGLES, masterNumberIndices[a], GL_UNSIGNED_INT, (char*) NULL+0);
glBindVertexArrayAPPLE(0);
}
glUseProgram(0);
}
void Init_FBO()
{
GLfloat border[] = {1.0f, 0.0f, 0.0f, 0.0f};
//glActiveTexture(GL_TEXTURE3);
glGenTextures(1, &depthTex);
glBindTexture(GL_TEXTURE_2D, depthTex);
glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT24,900,900, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, border);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE, GL_COMPARE_REF_TO_TEXTURE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FUNC, GL_LESS);
glBindTexture(GL_TEXTURE_2D,0);
glGenFramebuffers(1, &shadowFBO);
glBindFramebuffer(GL_FRAMEBUFFER, shadowFBO);
glDrawBuffer(GL_NONE);
glReadBuffer(GL_NONE);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthTex, 0);
glBindFramebuffer(GL_FRAMEBUFFER, 0); // go back to the default framebuffer
// check FBO status
GLenum FBOstatus = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER);
if(FBOstatus != GL_FRAMEBUFFER_COMPLETE)
{
printf("GL_FRAMEBUFFER_COMPLETE failed, CANNOT use FBO\n");
}
else
{
printf("Frame Buffer Done Succesfully\n");
}
}
void display()
{
glBindFramebuffer(GL_FRAMEBUFFER, shadowFBO);
generateShadowTex();
glBindFramebuffer(GL_FRAMEBUFFER, 0);
generateScene();
}