【发布时间】：2019-12-17 14:39:22
【问题描述】：
我正在尝试为地球应用置换贴图和镜面反射贴图，只为月球应用置换贴图。
我可以将高度贴图转移到法线贴图，但如果我使用相同的高度贴图来应用置换贴图，它就不会像我预期的那样工作..
这是示例图片
你可以看到地球和月球周围的颠簸，但没有实际的高度差异。
如果我对地球应用高光贴图，地球会变成这样
我只想让地球的海洋发光，但我的代码把地球变成了全黑，我只能看到地球上的一些白点......
这些纹理来自site
这是我的顶点着色器代码和片段着色器代码
"use strict";
const loc_aPosition = 3;
const loc_aNormal = 5;
const loc_aTexture = 7;
const VSHADER_SOURCE =
`#version 300 es
layout(location=${loc_aPosition}) in vec4 aPosition;
layout(location=${loc_aNormal}) in vec4 aNormal;
layout(location=${loc_aTexture}) in vec2 aTexCoord;
uniform mat4 uMvpMatrix;
uniform mat4 uModelMatrix; // Model matrix
uniform mat4 uNormalMatrix; // Transformation matrix of the normal
uniform sampler2D earth_disp;
uniform sampler2D moon_disp;
//uniform float earth_dispScale;
//uniform float moon_dispScale;
//uniform float earth_dispBias;
//uniform float moon_dispBias;
uniform bool uEarth;
uniform bool uMoon;
out vec2 vTexCoord;
out vec3 vNormal;
out vec3 vPosition;
void main()
{
float disp;
if(uEarth)
disp = texture(earth_disp, aTexCoord).r; //Extracting the color information from the image
else if(uMoon)
disp = texture(moon_disp, aTexCoord).r; //Extracting the color information from the image
vec4 displace = aPosition;
float displaceFactor = 2.0;
float displaceBias = 0.5;
if(uEarth || uMoon) //Using Displacement Mapping
{
displace += (displaceFactor * disp - displaceBias) * aNormal;
gl_Position = uMvpMatrix * displace;
}
else //Not using displacement mapping
gl_Position = uMvpMatrix * aPosition;
// Calculate the vertex position in the world coordinate
vPosition = vec3(uModelMatrix * aPosition);
vNormal = normalize(vec3(uNormalMatrix * aNormal));
vTexCoord = aTexCoord;
}`;
// Fragment shader program
const FSHADER_SOURCE =
`#version 300 es
precision mediump float;
uniform vec3 uLightColor; // Light color
uniform vec3 uLightPosition; // Position of the light source
uniform vec3 uAmbientLight; // Ambient light color
uniform sampler2D sun_color;
uniform sampler2D earth_color;
uniform sampler2D moon_color;
uniform sampler2D earth_bump;
uniform sampler2D moon_bump;
uniform sampler2D specularMap;
in vec3 vNormal;
in vec3 vPosition;
in vec2 vTexCoord;
out vec4 fColor;
uniform bool uIsSun;
uniform bool uIsEarth;
uniform bool uIsMoon;
vec2 dHdxy_fwd(sampler2D bumpMap, vec2 UV, float bumpScale)
{
vec2 dSTdx = dFdx( UV );
vec2 dSTdy = dFdy( UV );
float Hll = bumpScale * texture( bumpMap, UV ).x;
float dBx = bumpScale * texture( bumpMap, UV + dSTdx ).x - Hll;
float dBy = bumpScale * texture( bumpMap, UV + dSTdy ).x - Hll;
return vec2( dBx, dBy );
}
vec3 pertubNormalArb(vec3 surf_pos, vec3 surf_norm, vec2 dHdxy)
{
vec3 vSigmaX = vec3( dFdx( surf_pos.x ), dFdx( surf_pos.y ), dFdx( surf_pos.z ) );
vec3 vSigmaY = vec3( dFdy( surf_pos.x ), dFdy( surf_pos.y ), dFdy( surf_pos.z ) );
vec3 vN = surf_norm; // normalized
vec3 R1 = cross( vSigmaY, vN );
vec3 R2 = cross( vN, vSigmaX );
float fDet = dot( vSigmaX, R1 );
fDet *= ( float( gl_FrontFacing ) * 2.0 - 1.0 );
vec3 vGrad = sign( fDet ) * ( dHdxy.x * R1 + dHdxy.y * R2 );
return normalize( abs( fDet ) * surf_norm - vGrad );
}
void main()
{
vec2 dHdxy;
vec3 bumpNormal;
float bumpness = 1.0;
if(uIsSun)
fColor = texture(sun_color, vTexCoord);
else if(uIsEarth)
{
fColor = texture(earth_color, vTexCoord);
dHdxy = dHdxy_fwd(earth_bump, vTexCoord, bumpness);
}
else if(uIsMoon)
{
fColor = texture(moon_color, vTexCoord);
dHdxy = dHdxy_fwd(moon_bump, vTexCoord, bumpness);
}
// Normalize the normal because it is interpolated and not 1.0 in length any more
vec3 normal = normalize(vNormal);
// Calculate the light direction and make its length 1.
vec3 lightDirection = normalize(uLightPosition - vPosition);
// The dot product of the light direction and the orientation of a surface (the normal)
float nDotL;
if(uIsSun)
nDotL = 1.0;
else
nDotL = max(dot(lightDirection, normal), 0.0);
// Calculate the final color from diffuse reflection and ambient reflection
vec3 diffuse = uLightColor * fColor.rgb * nDotL;
vec3 ambient = uAmbientLight * fColor.rgb;
float specularFactor = texture(specularMap, vTexCoord).r; //Extracting the color information from the image
vec3 diffuseBump;
if(uIsEarth || uIsMoon)
{
bumpNormal = pertubNormalArb(vPosition, normal, dHdxy);
diffuseBump = min(diffuse + dot(bumpNormal, lightDirection), 1.1);
}
vec3 specular = vec3(0.0);
float shiness = 12.0;
vec3 lightSpecular = vec3(1.0);
if(uIsEarth && nDotL > 0.0)
{
vec3 v = normalize(-vPosition); // EyePosition
vec3 r = reflect(-lightDirection, bumpNormal); // Reflect from the surface
specular = lightSpecular * specularFactor * pow(dot(r, v), shiness);
}
//Update Final Color
if(uIsEarth)
fColor = vec4( (diffuse * diffuseBump * specular) + ambient, fColor.a); // Specular
else if(uIsMoon)
fColor = vec4( (diffuse * diffuseBump) + ambient, fColor.a);
else if(uIsSun)
fColor = vec4(diffuse + ambient, fColor.a);
}`;
你能告诉我在哪里检查吗？
【问题讨论】：
-
只是一个注释，但是在着色器中放置这么多条件是不正常的。而不是
uIsEarth、uIsMoon、uIsSun，只需制作一个没有条件的行星着色器并更改输入（制服和纹理）或制作3个单独的着色器，一个用于太阳，一个用于地球，一个用于如果他们真的需要做不同的事情，就去月球。 -
是的...这是真的..我尝试切换着色器，但是效果不佳，这就是我在代码中放置这么多布尔变量的原因..
-
PS：我仔细检查了位移，发现了一个问题。更新了答案