C++ 从FBO获得正确图像的反射纹理
我正在使用FBO捕捉四边形表面上方的反射。前提是在水面下移动摄影机,然后将场景渲染到fbo,然后恢复到原始查看位置,如下所示:C++ 从FBO获得正确图像的反射纹理,c++,opengl,glfw,C++,Opengl,Glfw,我正在使用FBO捕捉四边形表面上方的反射。前提是在水面下移动摄影机,然后将场景渲染到fbo,然后恢复到原始查看位置,如下所示: WaterFrameBuffer fbos; Water test(fbos.getReflectionTexture(), fbos.getRefractionTexture()); render->addWater(&test); while (!glfwWindowShouldClose(window)) { GLfloat curren
WaterFrameBuffer fbos;
Water test(fbos.getReflectionTexture(), fbos.getRefractionTexture());
render->addWater(&test);
while (!glfwWindowShouldClose(window))
{
GLfloat currentFrame = (float)glfwGetTime();
deltaTime = currentFrame - lastFrame;
lastFrame = currentFrame;
gameController->update(deltaTime);
//reflection buffer
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
fbos.bindReflectionFrameBuffer();
float distance = 2 * (gameController->getGameCamera()->GetCameraPosition().y - 0);
gameController->getGameCamera()->GetCameraPosition().y -= distance;
gameController->getGameCamera()->flipPitch();
render->renderScene();
gameController->getGameCamera()->GetCameraPosition().y += distance;
gameController->getGameCamera()->flipPitch();
glBindFramebuffer(GL_FRAMEBUFFER, 0);
glViewport(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
//refraction buffer
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
fbos.bindRefractionFrameBuffer();
render->renderScene();
glBindFramebuffer(GL_FRAMEBUFFER, 0);
glViewport(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
render->renderScene();
render->renderWater();
glfwSwapBuffers(window);
}
然而,我得到的结果是:
折射图像是正确的,但反射图像不是正确的。这是反射本身
这是我正在使用的片段着色器:
#version 330 core
in vec3 ourColor;
in vec4 clipSpace;
in vec2 texC;
out vec4 color;
// Texture samplers
uniform sampler2D reflectTex;
uniform sampler2D refractTex;
//uniform sampler2D dudvTex;
void main()
{
vec3 ndc = (clipSpace.xyz / clipSpace.w)/ 2.0 + 0.5;
vec2 reflectTexCoords = vec2(ndc.x, -ndc.y);
vec2 refractTexCoords = vec2(ndc.x, ndc.y);
//vec2 distortion1 = texture(dudvTex, vec2(texC.x, texC.y)).rg*2.0 - 1.0;
//reflectTexCoords += distortion1;
//refractTexCoords += distortion1;
vec4 reflect = texture(reflectTex, reflectTexCoords);
vec4 refract = texture(reflectTex, refractTexCoords);
color = reflect;//mix(reflect,refract,0.5);
}
顶点着色器:
#version 330 core
layout (location = 0) in vec3 position;
layout (location = 1) in vec3 color;
layout (location = 2) in vec2 texCoord;
out vec3 ourColor;
out vec4 clipSpace;
out vec2 texC;
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
const float tiling = 6.0;
void main()
{
clipSpace = projection*view*model *vec4(position, 1.0f);
gl_Position = clipSpace;
ourColor = color;
texC = texCoord;
}
有没有办法解决这个问题或者用另一种方法获得反射图像?我假设您已经为
GL\u texture\u wrap\S
和GL\u texture\u wrap\T
设置了纹理包裹参数,以GL\u CLAMP\u to\u EDGE
。看
这会导致任何纹理坐标被钳制到范围
[0+1/(2*textureSize),1-1/(2*textureSize)]
要解决问题,您必须使用纹理包裹参数GL\u REPEAT
,或者必须确保纹理坐标在[0.0,1.0]范围内
上图中的问题是纹理坐标(-ndc.y
)的y
分量的否定,这导致纹理坐标在[0.0,-1.0]范围内。将坐标移动到[1.0,0.0]范围内,并改用1.0-ndc.y
:
vec2 reflectTexCoords = vec2(ndc.x, 1.0 - ndc.y);
抱歉,这是片段着色器程序。Clipspace用于计算纹理要映射的像素,如果没有这个,纹理将随相机旋转。只是编辑了它,对此表示抱歉。好的,是的,只是尝试了一下。这是没有混合折射和反射的结果。“这导致任何纹理坐标0.0始终设置为0.0,而任何高于1.0的纹理坐标始终设置为1.0。”这并不准确。这是旧的和现在已弃用的
GL\u夹具
模式所做的<编码>夹紧到边缘夹紧到[0+1/(2*textureSize),1-1/(2*textureSize)]
,这是最外层texel的texel中心的坐标。效果非常好!我已经有了0,1范围内的纹理坐标,所以所做的只是将-ndc.y更改为1-ndc,y。谢谢你的帮助。