有一个问题,也许有人可以帮助我。我正在尝试使用 OpenGL 制作镜像效果。我画了一个透明的平面,一个用模板切割的“反射”场景,以及一个原始的。但我有一个完全不透明的“墙”而不是镜子。我知道这是因为第一次镜像平面渲染(以获得模板缓冲区)。但我不知道该怎么办:(这是代码:
void CMirror::draw(CSceneObject * curscene)
{
glPushMatrix();
glClearStencil(0.0f);
glClear(GL_STENCIL_BUFFER_BIT);
//Draw into the stencil buffer
glDisable(GL_LIGHTING);
glDisable(GL_TEXTURE_2D);
glStencilFunc(GL_ALWAYS, 1, 0);
glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE);
glEnable(GL_STENCIL_TEST);
glPushMatrix();
glTranslatef(this->coords[0], this->coords[1], this->coords[2]);
glScalef(this->size, this->size, this->size);
glColor4f(1, 0, 1, 0);
glBegin(GL_QUADS);
glVertex3f(0.0f, this->height / 2.0f, this->width / 2.0f);
glVertex3f(0.0f, this->height / -2.0f, this->width / 2.0f);
glVertex3f(0.0f, this->height / -2.0f, this->width / -2.0f);
glVertex3f(0.0f, this->height / 2.0f, this->width / -2.0f);
glEnd();
glPopMatrix();
glDisable(GL_STENCIL_TEST);
glEnable(GL_LIGHTING);
glEnable(GL_TEXTURE_2D);
//glClear(GL_COLOR_BUFFER_BIT);
//Draw the scene
glEnable(GL_STENCIL_TEST);
glStencilFunc(GL_EQUAL, 1, 255);
glPushMatrix();
glTranslatef( 2*this->coords[0], 2*this->coords[1], 2*this->coords[2]);
glScalef(-1.0f, 1.0f, 1.0f);
((CScene*)curscene)->draw();
glColor4f(0.0f, 0.30f, 0, 0.9);
((CScene*)curscene)->spline->draw();
((CScene*)curscene)->morph->draw();
glPopMatrix();
glDisable(GL_STENCIL_TEST);
//the mirror itself:
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glEnable(GL_BLEND);
glPushMatrix();
glTranslatef(this->coords[0], this->coords[1], this->coords[2]);
glScalef(this->size, this->size, this->size);
glColor4f(0, 0, 0, 0.9);
glBegin(GL_QUADS);
glVertex3f(0.0f, this->height / 2.0f, this->width / 2.0f);
glVertex3f(0.0f, this->height / -2.0f, this->width / 2.0f);
glVertex3f(0.0f, this->height / -2.0f, this->width / -2.0f);
glVertex3f(0.0f, this->height / 2.0f, this->width / -2.0f);
glEnd();
glPopMatrix();
glDisable(GL_BLEND);
glPopMatrix();
}