Question

我的阴影贴图似乎到处投射阴影，我不知道为什么。

这是我设置FBO和深度纹理的地方

glGenFramebuffers(1, &FramebufferName);
glBindFramebuffer(GL_FRAMEBUFFER, FramebufferName);

// Depth texture. Slower than a depth buffer, but you can sample it later in  your shader


glGenTextures(1, &shadowMap);
glBindTexture(GL_TEXTURE_2D, shadowMap);
glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT16, 800, 600, 0, GL_DEPTH_COMPONENT, GL_FLOAT, 0);
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_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);


glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, shadowMap, 0);

glDrawBuffer(GL_NONE); // No color buffer is drawn to.

                       // Always check that our framebuffer is ok

if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
    cout << "shadowMap fail" << endl;

这是我的两次传球

// clear the screen
glEnable(GL_CULL_FACE);
glClearColor(0.5f,0.5f,0.5f,1.0f);
glClear(GL_COLOR_BUFFER_BIT  | GL_DEPTH_BUFFER_BIT);

glm::mat4 projection(1.0);
projection = glm::perspective(float(60.0f*DEG_TO_RADIAN),800.0f/600.0f,1.0f,150.0f);
rt3d::setUniformMatrix4fv(shaderProgram, "projection", glm::value_ptr(projection));

GLfloat scale(1.0f); // just to allow easy scaling of complete scene

glm::mat4 modelview(1.0); // set base position for scene
mvStack.push(modelview);




for (int pass = 0; pass < 2; pass++) {
    if (pass == 0) {
        glUseProgram(shadowMapProgram);
        glm::vec3 lightInvDir = glm::vec3(lightPos.x, lightPos.y, lightPos.z);
        oldeye = eye;
        eye = lightInvDir;
        at = glm::vec3(0, 0, 0);
        up = glm::vec3(0, 1, 0);

        // Compute the MVP matrix from the light's point of view

        glm::mat4 depthViewMatrix = glm::lookAt(eye, at ,up);

        depthMVP = depthProjectionMatrix * depthViewMatrix * depthModelMatrix;

        glBindFramebuffer(GL_FRAMEBUFFER, FramebufferName);
        uniformIndex = glGetUniformLocation(shadowMapProgram, "depthMVP");
        glUniformMatrix4fv(uniformIndex, 1, GL_FALSE, &depthMVP[0][0]);


        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, shadowMap, 0);

        glDrawBuffer(GL_NONE); // No color buffer is drawn to.

        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        rt3d::setUniformMatrix4fv(shadowMapProgram, "projection", glm::value_ptr(depthProjectionMatrix));

        uniformIndex = glGetUniformLocation(shadowMapProgram, "modelMatrix");
        glUniformMatrix4fv(uniformIndex, 1, GL_FALSE, glm::value_ptr(depthModelMatrix));
        cout << uniformIndex << " DepthModelMatrix" << endl;


    }
    if (pass == 1) {

        glBindFramebuffer(GL_FRAMEBUFFER, 0);
        eye = oldeye;
        at = moveForward(eye, r, 1.0f);
        up = glm::vec3(0, 1, 0);

        glUseProgram(toonShaderProgram);
        glm::mat4 depthBiasMVP = biasMatrix*depthMVP;

        // Send our transformation to the currently bound shader,
        // in the "MVP" uniform
        //uniformIndex = glGetUniformLocation(toonShaderProgram, "depthBiasMVP");
    //  glUniformMatrix4fv(uniformIndex, 1, GL_FALSE, &depthBiasMVP[0][0]);
        //cout << uniformIndex << " depthBiasMVP" << endl;

        rt3d::setUniformMatrix4fv(toonShaderProgram, "depthBiasMVP", glm::value_ptr(depthBiasMVP));


        uniformIndex = glGetUniformLocation(toonShaderProgram, "shadowMap");
        glUniform1i(uniformIndex, shadowMap);
        //cout << uniformIndex << " shadowMap" << endl;
        rt3d::setUniformMatrix4fv(toonShaderProgram, "projection", glm::value_ptr(projection));

        uniformIndex = glGetUniformLocation(toonShaderProgram, "modelMatrix");
        glUniformMatrix4fv(uniformIndex, 1, GL_FALSE, glm::value_ptr(depthModelMatrix));
        cout << uniformIndex << " modelMatrix" << endl;


    }


    mvStack.top() = glm::lookAt(eye, at, up);
//render scene

我的阴影贴图着色器 .vert

 #version 330

// Input vertex data, different for all executions of this shader.
in vec3 in_Position;

// Values that stay constant for the whole mesh.
uniform mat4 depthMVP;
uniform mat4 modelMatrix;
uniform mat4 projection;



void main(){

vec4 vertexPosition = modelMatrix * vec4(in_Position,1.0);

gl_Position =  depthMVP * vertexPosition;

}

.frag

  #version 330


void main(){
// Not really needed, OpenGL does it anyway


gl_FragColor = vec4(gl_FragCoord.z);
}

和我的Phong着色器 .vert

...

out vec4 ShadowCoord;

uniform mat4 modelMatrix;




void main(void) {

 ...

gl_Position = projection * vertexPosition;



vec4 shadowPos = (modelMatrix * vec4(in_Position,1.0));

ShadowCoord = depthBiasMVP  * shadowPos;
ShadowCoord = ShadowCoord/ ShadowCoord.w;

.frag

  ....
  if ((ShadowCoord.x < 0 || ShadowCoord.x > 1 || ShadowCoord.y < 0 || ShadowCoord.y > 1 || ShadowCoord.z < 0 || ShadowCoord.z > 1)){
   visibility = 0.5f;
 }else{
    float shadowDepth = texture(shadowMap, ShadowCoord.xy).r;
    if(shadowDepth<ShadowCoord.z-bias)
        visibility = 0.0f;
 }



// Ambient intensity
vec4 ambientI = light.ambient * material.ambient;

// Diffuse intensity
vec4 diffuseI = light.diffuse * material.diffuse *visibility;
diffuseI = diffuseI * max(dot(normalize(ex_N),normalize(ex_L)),0);

// Specular intensity
// Calculate R - reflection of light


vec3 R = normalize(reflect(normalize(-ex_L),normalize(ex_N)));

vec4 specularI = light.specular * material.specular *visibility;
specularI = specularI * pow(max(dot(R,ex_V),0), material.shininess);


// Fragment colour
out_Color = (ambientI + diffuseI + specularI) * texture(textureUnit0, ex_TexCoord);

我真的无法弄清楚我做错了什么。我所有的场景都投射在阴影中。我尝试了各种各样的事情，包括在屏幕上渲染我的阴影贴图（如图所示），并使用不同的矩阵进行计算，但我仍然无法弄明白。

我计算我的ShadowCoords的空间是否重要，我一直在使用modelview，模型会更好吗？

Here is my scene

场景全都在阴影中

0 个答案: