[英]GLSL: When does the fragment shader exit / return
假設我們有以下片段着色器:
varying vec2 vUv; // uv coordinates
varying float vTexture; // texture index in array of textures
uniform sampler2D textures[2]; // number of textures
void main() {
int textureIndex = int(floor(vTexture)); // convert texture index to int for equality checks
if (textureIndex == 0) {
gl_FragColor = texture2D(textures[0], vUv);
}
if (textureIndex == 1) {
gl_FragColor = texture2D(textures[1], vUv);
}
}
如果通過此着色器獲得的給定值的textureIndex = 0,則該值是否將檢查第二個是否有條件,或者gl_FragColor的建立會使main()
函數“返回”或退出? 有沒有一種方法可以強制片段着色器在給定點退出或返回?
新答案 (特定於問題)
void main() {
int textureIndex = int(floor(vTexture)); // convert texture index to int for equality checks
if (textureIndex == 0) {
gl_FragColor = texture2D(textures[0], vUv);
}
if (textureIndex == 1) {
gl_FragColor = texture2D(textures[1], vUv);
}
// <--- HERE (ONCE IT RUNS THE CODE ABOVE, IT REACHES THE "END" AND EXITS)
}
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.