OpenGL Multitexturing GLSL — только одна текстура за один раз

Кажется, если я использую texture(texture0,textCoord) в течение одного раза, а затем я пытаюсь использовать его снова с другой текстурой texture(texture1,textCoord); возвращается (0,0,0,0); и я просто не знаю почему.

В моей программе, кажется, порядок рабочих, если DEFT работает, чем другие,
если я не использую глубину, то работает только цвет и т. д. (Depht, Color, Normal, Pos, Shine — это порядок)

this is the fragment shader :

uniform sampler2D tex0;
uniform sampler2D tex1;
uniform sampler2D tex2;
uniform sampler2D tex3;
uniform sampler2D depht;

void main()
{
float UNIT = 1./640. ;

//vec4 depht = texture(depht,gl_TexCoord[0].st);
vec4 color = texture(tex0,gl_TexCoord[0].st);
vec4 norma = texture(tex1,gl_TexCoord[0].st);
vec4 posit = texture(tex2,gl_TexCoord[0].st);
vec4 shine = texture(tex3,gl_TexCoord[0].st);if(false){
gl_FragColor=(  texture2D(tex0,gl_TexCoord[0].st +vec2(0,0))+
texture2D(tex0,gl_TexCoord[0].st +vec2(0,-UNIT))+
texture2D(tex0,gl_TexCoord[0].st +vec2(UNIT,-UNIT))+
texture2D(tex0,gl_TexCoord[0].st +vec2(UNIT,0))+
texture2D(tex0,gl_TexCoord[0].st +vec2(UNIT,UNIT))+
texture2D(tex0,gl_TexCoord[0].st +vec2(0,UNIT))+
texture2D(tex0,gl_TexCoord[0].st +vec2(-UNIT,UNIT))+
texture2D(tex0,gl_TexCoord[0].st +vec2(-UNIT,0))+
texture2D(tex0,gl_TexCoord[0].st +vec2(-UNIT,-UNIT)))/9.;
}else{
gl_FragColor=(norma+color);
}
}

это обязательная часть:

    fbotest.drawFBO();
DEFERRED.UseNow();
DrawGLScene();

fbotest.readFBO();
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

DEFERRED2.UseNow();

//glBlendFunc (GL_ONE, GL_ONE);
glEnable( GL_BLEND );

glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, fbotest.Color);
glEnable(GL_TEXTURE_2D);

glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, fbotest.Normal);
glEnable(GL_TEXTURE_2D);

glActiveTexture(GL_TEXTURE2);
glBindTexture(GL_TEXTURE_2D, fbotest.Pos);
glEnable(GL_TEXTURE_2D);

glActiveTexture(GL_TEXTURE3);
glBindTexture(GL_TEXTURE_2D, fbotest.Shine);
glEnable(GL_TEXTURE_2D);

glActiveTexture(GL_TEXTURE4);
glBindTexture(GL_TEXTURE_2D, fbotest.Depht);
glEnable(GL_TEXTURE_2D);

glUniform1i(glGetUniformLocation(DEFERRED2.PR,"tex0"),0);
glUniform1i(glGetUniformLocation(DEFERRED2.PR,"tex1"),1);
glUniform1i(glGetUniformLocation(DEFERRED2.PR,"tex2"),2);
glUniform1i(glGetUniformLocation(DEFERRED2.PR,"tex3"),3);
glUniform1i(glGetUniformLocation(DEFERRED2.PR,"depht"),4);

glLoadIdentity();
glBegin(GL_QUADS);
glMultiTexCoord2f(GL_TEXTURE0, 1.0, 0.0);
glMultiTexCoord2f(GL_TEXTURE1, 1.0, 0.0);
glMultiTexCoord2f(GL_TEXTURE2, 1.0, 0.0);
glMultiTexCoord2f(GL_TEXTURE3, 1.0, 0.0);
glMultiTexCoord2f(GL_TEXTURE4, 1.0, 0.0);
glVertex3f( 1,-1,-3);
glMultiTexCoord2f(GL_TEXTURE0, 1.0, 1.0);
glMultiTexCoord2f(GL_TEXTURE1, 1.0, 1.0);
glMultiTexCoord2f(GL_TEXTURE2, 1.0, 1.0);
glMultiTexCoord2f(GL_TEXTURE3, 1.0, 1.0);
glMultiTexCoord2f(GL_TEXTURE4, 1.0, 1.0);
glVertex3f( 1,1 ,-3);
glMultiTexCoord2f(GL_TEXTURE0, 0.0, 1.0);
glMultiTexCoord2f(GL_TEXTURE1, 0.0, 1.0);
glMultiTexCoord2f(GL_TEXTURE2, 0.0, 1.0);
glMultiTexCoord2f(GL_TEXTURE3, 0.0, 1.0);
glMultiTexCoord2f(GL_TEXTURE4, 0.0, 1.0);
glVertex3f( -1,1,-3);
glMultiTexCoord2f(GL_TEXTURE0, 0.0, 0.0);
glMultiTexCoord2f(GL_TEXTURE1, 0.0, 0.0);
glMultiTexCoord2f(GL_TEXTURE2, 0.0, 0.0);
glMultiTexCoord2f(GL_TEXTURE3, 0.0, 0.0);
glMultiTexCoord2f(GL_TEXTURE4, 0.0, 0.0);
glVertex3f(-1,-1,-3);
glEnd();

glActiveTextureARB(GL_TEXTURE4);
glBindTexture(GL_TEXTURE_2D, 0);
glActiveTextureARB(GL_TEXTURE3);
glBindTexture(GL_TEXTURE_2D, 0);
glActiveTextureARB(GL_TEXTURE2);
glBindTexture(GL_TEXTURE_2D, 0);
glActiveTextureARB(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, 0);
glActiveTextureARB(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, 0);
glDisable( GL_BLEND );

и это может быть класс FBO:

    class deferred{
public :
unsigned int FBO;
unsigned int Depht;
unsigned int Color;
unsigned int Normal;
unsigned int Pos;
unsigned int Shine;

deferred();
void initFBO();
void readFBO();
void drawFBO();

};

void deferred::readFBO(){
glBindFramebuffer(GL_DRAW_FRAMEBUFFER,0);
glBindFramebuffer(GL_READ_FRAMEBUFFER,FBO);
}

void deferred::drawFBO(){
glBindFramebuffer(GL_READ_FRAMEBUFFER,0);
glBindFramebuffer(GL_DRAW_FRAMEBUFFER,FBO);
}

deferred::deferred(){
FBO     =0;
Depht   =0;
Color   =0;
Normal  =0;
Pos     =0;
Shine   =0;
}

void deferred::initFBO(){
glGenFramebuffers(1, &FBO);
glBindFramebuffer(GL_DRAW_FRAMEBUFFER, FBO);glGenTextures(1,&Depht );
glGenTextures(1,&Color );
glGenTextures(1,&Normal);
glGenTextures(1,&Pos   );
glGenTextures(1,&Shine );

int WindowWidth = Ww;
int WindowHeight= Wh;

glBindTexture(GL_TEXTURE_2D, Color);
glTexImage2D (GL_TEXTURE_2D, 0, GL_RGB32F, WindowWidth, WindowHeight, 0, GL_RGB, GL_FLOAT, NULL);
glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, Color, 0);

glBindTexture(GL_TEXTURE_2D, Normal);
glTexImage2D (GL_TEXTURE_2D, 0, GL_RGB32F, WindowWidth, WindowHeight, 0, GL_RGB, GL_FLOAT, NULL);
glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT1, GL_TEXTURE_2D, Normal, 0);

glBindTexture(GL_TEXTURE_2D, Pos);
glTexImage2D (GL_TEXTURE_2D, 0, GL_RGB32F, WindowWidth, WindowHeight, 0, GL_RGB, GL_FLOAT, NULL);
glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT2, GL_TEXTURE_2D, Pos, 0);

glBindTexture(GL_TEXTURE_2D, Shine);
glTexImage2D (GL_TEXTURE_2D, 0, GL_RGB32F, WindowWidth, WindowHeight, 0, GL_RGB, GL_FLOAT, NULL);
glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT3, GL_TEXTURE_2D, Shine, 0);

glBindTexture(GL_TEXTURE_2D, Depht);
glTexImage2D (GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT32F, WindowWidth, WindowHeight, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, Depht, 0);

GLenum DrawBuffers[] = { GL_COLOR_ATTACHMENT0,
GL_COLOR_ATTACHMENT1,
GL_COLOR_ATTACHMENT2,
GL_COLOR_ATTACHMENT3};

glDrawBuffers(4, DrawBuffers);

GLenum Status = glCheckFramebufferStatus(GL_FRAMEBUFFER);

if (Status != GL_FRAMEBUFFER_COMPLETE) {
cout <<"Frame Buffer ERROR : "<< Status << "\n" ;
}

glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
}