我目前正在學習如何級聯陰影貼圖的工作,所以我一直在試圖讓一個陰影貼圖以適應視錐沒有閃閃發光。我使用的1近/遠平面到10000我的相機投影,這是我計算的光正交矩陣方式:級聯陰影貼圖波光
GLfloat far = -INFINITY;
GLfloat near = INFINITY;
//Multiply all the world space frustum corners with the view matrix of the light
Frustum cameraFrustum = CameraMan.getActiveCamera()->mFrustum;
lightViewMatrix = glm::lookAt((cameraFrustum.frustumCenter - glm::vec3(-0.447213620f, -0.89442790f, 0.0f)), cameraFrustum.frustumCenter, glm::vec3(0.0f, 0.0f, 1.0f));
glm::vec3 arr[8];
for (unsigned int i = 0; i < 8; ++i)
arr[i] = glm::vec3(lightViewMatrix * glm::vec4(cameraFrustum.frustumCorners[i], 1.0f));
glm::vec3 minO = glm::vec3(INFINITY, INFINITY, INFINITY);
glm::vec3 maxO = glm::vec3(-INFINITY, -INFINITY, -INFINITY);
for (auto& vec : arr)
{
minO = glm::min(minO, vec);
maxO = glm::max(maxO, vec);
}
far = maxO.z;
near = minO.z;
//Get the longest diagonal of the frustum, this along with texel sized increments is used to keep the shadows from shimmering
//far top right - near bottom left
glm::vec3 longestDiagonal = cameraFrustum.frustumCorners[0] - cameraFrustum.frustumCorners[6];
GLfloat lengthOfDiagonal = glm::length(longestDiagonal);
longestDiagonal = glm::vec3(lengthOfDiagonal);
glm::vec3 borderOffset = (longestDiagonal - (maxO - minO)) * glm::vec3(0.5f, 0.5f, 0.5f);
borderOffset *= glm::vec3(1.0f, 1.0f, 0.0f);
maxO += borderOffset;
minO -= borderOffset;
GLfloat worldUnitsPerTexel = lengthOfDiagonal/1024.0f;
glm::vec3 vWorldUnitsPerTexel = glm::vec3(worldUnitsPerTexel, worldUnitsPerTexel, 0.0f);
minO /= vWorldUnitsPerTexel;
minO = glm::floor(minO);
minO *= vWorldUnitsPerTexel;
maxO /= vWorldUnitsPerTexel;
maxO = glm::floor(maxO);
maxO *= vWorldUnitsPerTexel;
lightOrthoMatrix = glm::ortho(minO.x, maxO.x, minO.y, maxO.y, near, far);
使用的最長對角線來抵消視錐似乎被工作作爲陰影貼圖似乎並沒有縮小/縮放四處尋找時,卻使用https://msdn.microsoft.com/en-us/library/windows/desktop/ee416324(v=vs.85).aspx描述紋理像素大小的增量已經沒有任何影響。我正在使用一個非常大的場景進行測試,這導致我的陰影貼圖分辨率較低,但是我希望能夠在將視錐分割開來之前獲得適合視圖平截頭體的穩定陰影。很難從圖像中說,但不是由微軟提出的解決方案降低了波光粼粼的效果:
你是什麼意思「波光粼粼」是什麼意思? –
https://www.youtube.com/watch?v=PxbGUOC_UeA這段視頻解釋了它,我的場景看起來像視頻的第一部分,而提出的解決方案我,微軟應該穩定下來 – Johan