我正在开发 LibGDX 游戏中菜单的 UI。然而，UI 背后的背景应该看起来像 Shadertoy 着色器。我将 Shadertoy 脚本翻译成 GLSL，并在没有 UI 的情况下成功运行和渲染。但是，当我使用
stage.draw();
public class ShaderToyShader implements Disposable {
private ShaderProgram shaderToy;
private Mesh fullScreenMesh;
private Texture iChannel0, iChannel1;
public ShaderToyShader(FileHandle fragment, Texture iChannel0, Texture iChannel1) {
this.iChannel0 = iChannel0;
this.iChannel1 = iChannel1;
shaderToy = new ShaderProgram(Gdx.files.internal("shaders/menushader/menuShader.vert"), fragment);
if (!shaderToy.isCompiled())
Gdx.app.error("Shader", "Shader compilation failed: " + shaderToy.getLog());
fullScreenMesh = createFullScreenQuad();
}
private Mesh createFullScreenQuad() {
Mesh mesh = new Mesh(true, 4, 6, new VertexAttribute(VertexAttributes.Usage.Position, 2, "vPos"));
mesh.setVertices(new float[] {
-1f, -1f,
1f, -1f,
-1f, 1f,
1f, 1f
});
mesh.setIndices(new short[] { 0, 1, 2, 1, 2, 3 });
return mesh;
}
public void uploadAllUniforms() {
float screenWidth = Gdx.graphics.getWidth();
float screenHeight = Gdx.graphics.getHeight();
shaderToy.setUniformf("iResolution", screenWidth, screenHeight, 0); // viewport resolution
shaderToy.setUniformf("iTime", TimeUtils.millis() / 1000f); // shader playback time
shaderToy.setUniformf("iTimeDelta", Gdx.graphics.getDeltaTime()); // render time
shaderToy.setUniformf("iFrameRate", 60f); // shader frame rate
shaderToy.setUniformi("iFrame", (int) Gdx.graphics.getFrameId()); // shader playback frame
shaderToy.setUniformi("iChannel0", 0); // bind iChannel0 to texture unit 0
iChannel0.bind(0);
shaderToy.setUniformi("iChannel1", 1); // bind iChannel1 to texture unit 1
iChannel1.bind(1);
shaderToy.setUniform2fv("iChannelTime", new float[] {0f, 0f, 0f, 0f}, 0, 4);
shaderToy.setUniform3fv("iChannelResolution", new float[] {screenWidth, screenHeight, 0f}, 0, 3);
Vector2 mousePos = new Vector2(Gdx.input.getX(), Gdx.input.getY());
Vector2 click = new Vector2(Gdx.input.isButtonPressed(Input.Buttons.LEFT) ? 1 : 0, Gdx.input.isButtonPressed(Input.Buttons.RIGHT) ? 1 : 0);
shaderToy.setUniform4fv("iMouse", new float[] {mousePos.x, mousePos.y, click.x, click.y}, 0, 4);
shaderToy.setUniform4fv("iDate", new float[] {0, 0, 0, 0}, 0, 4); // date
}
public void render() {
uploadAllUniforms();
shaderToy.bind();
fullScreenMesh.render(shaderToy, GL_TRIANGLES);
}
@Override
public void dispose() {
shaderToy.dispose();
fullScreenMesh.dispose();
iChannel0.dispose();
iChannel1.dispose();
}
public ShaderProgram getShaderToy() {
return shaderToy;
}
}
这是菜单类：
import java.nio.file.attribute.UserPrincipal;
import static com.badlogic.gdx.graphics.GL20.*;
public class MenuScreen implements Screen {
private final MainGame mainGame;
private final Stage stage;
private BitmapFont gameTitleFont;
private final Player player;
private final ShaderToyShader menuBackground;
private final SpriteBatch batch;
@Inject
public MenuScreen(MainGame mainGame, SpriteBatch spriteBatch, Player player) {
this.batch = spriteBatch;
this.mainGame = mainGame;
System.out.println(Gdx.graphics.getGLVersion().getDebugVersionString());
var iChannel0 = new Texture(Gdx.files.internal("shaders/menushader/shadertoy0.png"));
iChannel0.setFilter(Texture.TextureFilter.Nearest, Texture.TextureFilter.Nearest);
iChannel0.setWrap(Texture.TextureWrap.Repeat, Texture.TextureWrap.Repeat);
var iChannel1 = new Texture(Gdx.files.internal("shaders/menushader/shadertoy1.png"));
iChannel1.setFilter(Texture.TextureFilter.Nearest, Texture.TextureFilter.Nearest);
iChannel1.setWrap(Texture.TextureWrap.Repeat, Texture.TextureWrap.Repeat);
menuBackground = new ShaderToyShader(Gdx.files.internal("shaders/menushader/menuShader.frag"), iChannel0, iChannel1);
stage = new Stage(new ExtendViewport(Gdx.graphics.getWidth(), Gdx.graphics.getHeight()), spriteBatch);
this.player = player;
Gdx.input.setInputProcessor(stage);
}
@Override
public void show() {
FreeTypeFontGenerator generator = new FreeTypeFontGenerator(Gdx.files.internal("Nightcore Demo.ttf"));
FreeTypeFontGenerator.FreeTypeFontParameter parameter = new FreeTypeFontGenerator.FreeTypeFontParameter();
parameter.size = 50;
parameter.color = Color.WHITE;
gameTitleFont = generator.generateFont(parameter);
generator.dispose();
Table table = new Table();
table.top().center();
table.setFillParent(true);
stage.addActor(table);
Label.LabelStyle titleStyle = new Label.LabelStyle(gameTitleFont, Color.RED);
Label titleL1 = new Label("Hollows Curse", titleStyle);
titleL1.setAlignment(Align.center);
table.add(titleL1);
table.row();
Label titleL2 = new Label("Pursuit Of The Headless Horseman", titleStyle);
table.add(titleL2);
table.row();
TextButton.TextButtonStyle buttonStyle = new TextButton.TextButtonStyle();
buttonStyle.font = gameTitleFont;
buttonStyle.fontColor = Color.RED;
buttonStyle.overFontColor = Color.WHITE;
TextButton playButton = new TextButton("Play now", buttonStyle);
playButton.addListener(new ClickListener() {
@Override
public void clicked(InputEvent event, float x, float y) {
player.postLoad();
mainGame.switchScreen(MainGame.ScreenType.GAME_SCREEN);
}
});
table.add(playButton).padTop(10f);
table.row();
TextButton exitButton = new TextButton("Exit", buttonStyle);
exitButton.addListener(new ClickListener() {
@Override
public void clicked(InputEvent event, float x, float y) {
Gdx.app.exit();
}
});
table.add(exitButton).padTop(10f);
table.row();
}
@Override
public void render(float delta) {
ScreenUtils.clear(0, 0, 0, 0);
var previousShader = batch.getShader();
Gdx.gl.glDisable(GL_DEPTH_TEST);
menuBackground.render();
stage.act();
previousShader.bind();
Gdx.gl.glEnable(GL_DEPTH_TEST);
Gdx.gl.glDepthFunc(GL_ALWAYS);
stage.draw();
}
@Override
public void resize(int width, int height) {
stage.getViewport().update(width, height, true);
}
@Override
public void pause() {
}
@Override
public void resume() {
}
@Override
public void hide() {
}
@Override
public void dispose() {
stage.dispose();
menuBackground.dispose();
}
}
这是顶点着色器：
#version 330 core
layout(location = 0) in vec2 vPos; // Vertex position attribute
void main() {
gl_Position = vec4(vPos, 1., 1.);
}
这是片段着色器：
// Jack-o'-lantern
// @P_Malin
// A little shadertoy doodle for halloween
#define kRaymarchMaxIter 64
#define kBounceCount 1
//#define SCENE_DOMAIN_REPEAT
varying out vec4 fragColor;
uniform vec3 iResolution; // viewport resolution (in pixels)
uniform float iTime; // shader playback time (in seconds)
uniform float iTimeDelta; // render time (in seconds)
uniform float iFrameRate; // shader frame rate
uniform int iFrame; // shader playback frame
uniform float iChannelTime[4]; // channel playback time (in seconds)
uniform vec3 iChannelResolution[4]; // channel resolution (in pixels)
uniform vec4 iMouse; // mouse pixel coords. xy: current (if MLB down), zw: click
uniform sampler2D iChannel0;
uniform sampler2D iChannel1;
float kFarClip=100.0;
// Declaring functions
vec2 GetWindowCoord( const in vec2 vUV );
vec3 GetCameraRayDir( const in vec2 vWindow, const in vec3 vCameraPos, const in vec3 vCameraTarget );
vec3 GetSceneColour( in vec3 vRayOrigin, in vec3 vRayDir );
vec3 ApplyPostFX( const in vec2 vUV, const in vec3 vInput );
float GetCarving2dDistance(const in vec2 vPos );
vec3 vLightPos = vec3(0.0, -0.5, 0.0);
vec3 vLightColour = vec3(1.0, 0.8, 0.4);
float fCarving = 1.0;
// from https://www.shadertoy.com/view/4djSRW
float hash(float p)
{
vec2 p2 = fract(vec2(p * 5.3983, p * 5.4427));
p2 += dot(p2.yx, p2.xy + vec2(21.5351, 14.3137));
return fract(p2.x * p2.y * 95.4337);
}
void main()
{
vec2 vUV = gl_FragCoord.xy / iResolution.xy;
vLightColour *= hash(iTime) * 0.2 + 0.8;
float fDist = 7.0;
float fAngle = radians(190.0) + sin(iTime * 0.25) * 0.2;
float fHeight = 2.0 + sin(iTime * 0.1567) * 1.5;
vec2 vMouse = iMouse.xy / iResolution.xy;
if(iMouse.z > 0.0)
{
fAngle = vMouse.x * 2.0 * 3.14;
fHeight = vMouse.y * fDist;
}
vec3 vCameraPos = vec3(sin(fAngle) * fDist, fHeight, cos(fAngle) * fDist);
vec3 vCameraTarget = vec3(0.0, -0.5, 0.0);
vec3 vRayOrigin = vCameraPos;
vec3 vRayDir = GetCameraRayDir( GetWindowCoord(vUV), vCameraPos, vCameraTarget );
vec3 vResult = GetSceneColour(vRayOrigin, vRayDir);
vec3 vFinal = ApplyPostFX( vUV, vResult );
fragColor = vec4( vResult, 1.0 );
}
// function impls
// CAMERA
vec2 GetWindowCoord( const in vec2 vUV )
{
vec2 vWindow = vUV * 2.0 - 1.0;
vWindow.x *= iResolution.x / iResolution.y;
return vWindow;
}
vec3 GetCameraRayDir( const in vec2 vWindow, const in vec3 vCameraPos, const in vec3 vCameraTarget )
{
vec3 vForward = normalize(vCameraTarget - vCameraPos);
vec3 vRight = normalize(cross(vec3(0.0, 1.0, 0.0), vForward));
vec3 vUp = normalize(cross(vForward, vRight));
vec3 vDir = normalize(vWindow.x * vRight + vWindow.y * vUp + vForward * 1.5);
return vDir;
}
// POSTFX
vec3 ApplyVignetting( const in vec2 vUV, const in vec3 vInput )
{
vec2 vOffset = (vUV - 0.5) * sqrt(2.0);
float fDist = dot(vOffset, vOffset);
const float kStrength = 0.95;
const float kPower = 1.5;
return vInput * ((1.0 - kStrength) + kStrength * pow(1.0 - fDist, kPower));
}
vec3 ApplyTonemap( const in vec3 vLinear )
{
float kExposure = 1.0;
if(iTime < 2.0)
{
kExposure = iTime / 2.0;
}
return 1.0 - exp2(vLinear * -kExposure);
}
vec3 ApplyGamma( const in vec3 vLinear )
{
const float kGamma = 2.2;
return pow(vLinear, vec3(1.0/kGamma));
}
vec3 ApplyBlackLevel( const in vec3 vColour )
{
float fBlackLevel = 0.1;
return vColour / (1.0 - fBlackLevel) - fBlackLevel;
}
vec3 ApplyPostFX( const in vec2 vUV, const in vec3 vInput )
{
vec3 vTemp = ApplyVignetting( vUV, vInput );
vTemp = ApplyTonemap(vTemp);
vTemp = ApplyGamma(vTemp);
vTemp = ApplyBlackLevel(vTemp);
return vTemp;
}
// RAYTRACE
struct C_Intersection
{
vec3 vPos;
float fDist;
vec3 vNormal;
vec3 vUVW;
float fObjectId;
};
float GetCarving2dDistance(const in vec2 vPos )
{
if(fCarving < 0.0)
return 10.0;
float fMouthDist = length(vPos.xy + vec2(0.0, -0.5)) - 1.5;
float fMouthDist2 = length(vPos.xy + vec2(0.0, -1.1 - 0.5)) - 2.0;
if(-fMouthDist2 > fMouthDist )
{
fMouthDist = -fMouthDist2;
}
float fFaceDist = fMouthDist;
vec2 vNosePos = vPos.xy + vec2(0.0, -0.5);
vNosePos.x = abs(vNosePos.x);
float fNoseDist = dot(vNosePos.xy, normalize(vec2(1.0, 0.5)));
fNoseDist = max(fNoseDist, -(vNosePos.y + 0.5));
if(fNoseDist < fFaceDist)
{
fFaceDist = fNoseDist;
}
vec2 vEyePos = vPos.xy;
vEyePos.x = abs(vEyePos.x);
vEyePos.x -= 1.0;
vEyePos.y -= 1.0;
float fEyeDist = dot(vEyePos.xy, normalize(vec2(-1.0, 1.5)));
fEyeDist = max(fEyeDist, dot(vEyePos.xy, normalize(vec2(1.0, 0.5))));
fEyeDist = max(fEyeDist, -0.5+dot(vEyePos.xy, normalize(vec2(0.0, -1.0))));
if(fEyeDist < fFaceDist)
{
fFaceDist = fEyeDist;
}
return fFaceDist;
}
float GetCarvingDistance(const in vec3 vPos )
{
float fDist = (length(vPos * vec3(1.0, 1.4, 1.0)) - 2.7) / 1.5;
float fFaceDist = GetCarving2dDistance(vPos.xy);
float fRearDist = vPos.z;
if(fRearDist > fFaceDist)
{
fFaceDist = fRearDist;
}
if(fFaceDist < fDist )
{
fDist = fFaceDist;
}
float fR = length(vPos.xz);
float fLidDist = dot( vec2(fR, vPos.y), normalize(vec2(1.0, -1.5)));
fLidDist = abs(fLidDist) - 0.03;
if(fLidDist < fDist )
{
fDist = fLidDist;
}
return fDist;
}
float GetPumpkinDistance( out vec4 vOutUVW_Id, const in vec3 vPos )
{
vec3 vSphereOrigin = vec3(0.0, 0.0, 0.0);
float fSphereRadius = 3.0;
vec3 vOffset = vPos - vSphereOrigin;
float fFirstDist = length(vOffset);
float fOutDist;
if(fFirstDist > 3.5)
{
fOutDist = fFirstDist - fSphereRadius;
}
else
{
float fAngle1 = atan(vOffset.x, vOffset.z);
float fSin = sin(fAngle1 * 10.0);
fSin = 1.0 - sqrt(abs(fSin));
vOffset *= 1.0 + fSin * vec3(0.05, 0.025, 0.05);
vOffset.y *= 1.0 + 0.5 * (fSphereRadius - length(vOffset.xz)) / fSphereRadius;
fOutDist = length(vOffset) - fSphereRadius;
}
vec4 vSphere1UVW_Id = vec4(normalize(vPos - vSphereOrigin), 3.0);
vOutUVW_Id = vSphere1UVW_Id;
vec3 vStalkOffset = vPos;
vStalkOffset.x += -(vStalkOffset.y - fSphereRadius) * 0.1;
float fDist2d = length(vStalkOffset.xz);
float fStalkDist = fDist2d - 0.2;
fStalkDist = max(fStalkDist, vPos.y - 2.5 + vPos.x * 0.25);
fStalkDist = max(fStalkDist, -vPos.y);
if( fStalkDist < fOutDist )
{
fOutDist = fStalkDist;
vOutUVW_Id = vSphere1UVW_Id;
vOutUVW_Id.w = 2.0;
}
return fOutDist;
}
float GetSceneDistance( out vec4 vOutUVW_Id, const in vec3 vPos )
{
float fFloorDist = vPos.y + 2.0;
vec4 vFloorUVW_Id = vec4(vPos.xz, 0.0, 1.0);
vec3 vPumpkinDomain = vPos;
#ifdef SCENE_DOMAIN_REPEAT
float fRepeat = 12.0;
float fOffset = (fRepeat * 0.5);
vPumpkinDomain.xz = fract((vPos.xz + fOffset) / fRepeat) * fRepeat - fOffset;
#endif
float fOutDist = fFloorDist;
vOutUVW_Id = vFloorUVW_Id;
vec4 vPumpkinUVW_Id;
float fPumpkinDist = GetPumpkinDistance( vPumpkinUVW_Id, vPumpkinDomain );
float fCarvingDist = GetCarvingDistance( vPumpkinDomain );
if(-fCarvingDist > fPumpkinDist)
{
fPumpkinDist = -fCarvingDist;
vPumpkinUVW_Id = vec4(4.0);
}
if(fPumpkinDist < fOutDist)
{
fOutDist = fPumpkinDist;
vOutUVW_Id = vPumpkinUVW_Id;
}
return fOutDist;
}
vec3 GetSceneNormal(const in vec3 vPos)
{
const float fDelta = 0.001;
vec3 vDir1 = vec3( 1.0, -1.0, -1.0);
vec3 vDir2 = vec3(-1.0, -1.0, 1.0);
vec3 vDir3 = vec3(-1.0, 1.0, -1.0);
vec3 vDir4 = vec3( 1.0, 1.0, 1.0);
vec3 vOffset1 = vDir1 * fDelta;
vec3 vOffset2 = vDir2 * fDelta;
vec3 vOffset3 = vDir3 * fDelta;
vec3 vOffset4 = vDir4 * fDelta;
vec4 vUnused;
float f1 = GetSceneDistance( vUnused, vPos + vOffset1 );
float f2 = GetSceneDistance( vUnused, vPos + vOffset2 );
float f3 = GetSceneDistance( vUnused, vPos + vOffset3 );
float f4 = GetSceneDistance( vUnused, vPos + vOffset4 );
vec3 vNormal = vDir1 * f1 + vDir2 * f2 + vDir3 * f3 + vDir4 * f4;
return normalize( vNormal );
}
void TraceScene( out C_Intersection outIntersection, const in vec3 vOrigin, const in vec3 vDir )
{
vec4 vUVW_Id = vec4(0.0);
vec3 vPos = vec3(0.0);
float t = 0.01;
for(int i=0; i<kRaymarchMaxIter; i++)
{
vPos = vOrigin + vDir * t;
float fDist = GetSceneDistance(vUVW_Id, vPos);
t += fDist;
if(abs(fDist) < 0.001)
{
break;
}
if(t > 100.0)
{
t = kFarClip;
vPos = vOrigin + vDir * t;
vUVW_Id = vec4(0.0);
break;
}
}
outIntersection.fDist = t;
outIntersection.vPos = vPos;
outIntersection.vNormal = GetSceneNormal(vPos);
outIntersection.vUVW = vUVW_Id.xyz;
outIntersection.fObjectId = vUVW_Id.w;
}
float TraceShadow( const in vec3 vOrigin, const in vec3 vDir, const in float fDist )
{
C_Intersection shadowIntersection;
TraceScene(shadowIntersection, vOrigin, vDir);
if(shadowIntersection.fDist < fDist)
{
return 0.0;
}
return 1.0;
}
float GetSSS( const in vec3 vPos, const in vec3 vLightPos )
{
vec3 vLightToPos = vPos - vLightPos;
vec3 vDir = normalize(vLightToPos);
C_Intersection intersection;
TraceScene(intersection, vLightPos, vDir);
float fOpticalDepth = length(vLightToPos) - intersection.fDist;
fOpticalDepth = max(0.00001, fOpticalDepth);
return exp2( fOpticalDepth * -8.0 );
}
// LIGHTING
float GIV( float dotNV, float k)
{
return 1.0 / ((dotNV + 0.0001) * (1.0 - k)+k);
}
void AddLighting(inout vec3 vDiffuseLight, inout vec3 vSpecularLight, const in vec3 vViewDir, const in vec3 vLightDir, const in vec3 vNormal, const in float fSmoothness, const in vec3 vLightColour)
{
vec3 vH = normalize( -vViewDir + vLightDir );
float fNDotL = clamp(dot(vLightDir, vNormal), 0.0, 1.0);
float fNDotV = clamp(dot(-vViewDir, vNormal), 0.0, 1.0);
float fNDotH = clamp(dot(vNormal, vH), 0.0, 1.0);
float alpha = 1.0 - fSmoothness;
alpha = alpha * alpha;
// D
float alphaSqr = alpha * alpha;
float pi = 3.14159;
float denom = fNDotH * fNDotH * (alphaSqr - 1.0) + 1.0;
float d = alphaSqr / (pi * denom * denom);
float k = alpha / 2.0;
float vis = GIV(fNDotL, k) * GIV(fNDotV, k);
float fSpecularIntensity = d * vis * fNDotL;
vSpecularLight += vLightColour * fSpecularIntensity;
vDiffuseLight += vLightColour * fNDotL;
}
void AddPointLight(inout vec3 vDiffuseLight, inout vec3 vSpecularLight, const in vec3 vViewDir, const in vec3 vPos, const in vec3 vNormal, const in float fSmoothness, const in vec3 vLightPos, const in vec3 vLightColour)
{
vec3 vToLight = vLightPos - vPos;
float fDistance2 = dot(vToLight, vToLight);
float fAttenuation = 100.0 / (fDistance2);
vec3 vLightDir = normalize(vToLight);
vec3 vShadowRayDir = vLightDir;
vec3 vShadowRayOrigin = vPos + vShadowRayDir * 0.01;
float fShadowFactor = TraceShadow(vShadowRayOrigin, vShadowRayDir, length(vToLight));
AddLighting(vDiffuseLight, vSpecularLight, vViewDir, vLightDir, vNormal, fSmoothness, vLightColour * fShadowFactor * fAttenuation);
}
float AddDirectionalLight(inout vec3 vDiffuseLight, inout vec3 vSpecularLight, const in vec3 vViewDir, const in vec3 vPos, const in vec3 vNormal, const in float fSmoothness, const in vec3 vLightDir, const in vec3 vLightColour)
{
float fAttenuation = 1.0;
vec3 vShadowRayDir = -vLightDir;
vec3 vShadowRayOrigin = vPos + vShadowRayDir * 0.01;
float fShadowFactor = TraceShadow(vShadowRayOrigin, vShadowRayDir, 10.0);
AddLighting(vDiffuseLight, vSpecularLight, vViewDir, -vLightDir, vNormal, fSmoothness, vLightColour * fShadowFactor * fAttenuation);
return fShadowFactor;
}
void AddDirectionalLightFlareToFog(inout vec3 vFogColour, const in vec3 vRayDir, const in vec3 vLightDir, const in vec3 vLightColour)
{
float fDirDot = clamp(dot(-vLightDir, vRayDir), 0.0, 1.0);
float kSpreadPower = 4.0;
vFogColour += vLightColour * pow(fDirDot, kSpreadPower);
}
// SCENE MATERIALS
void GetSurfaceInfo(out vec3 vOutAlbedo, out vec3 vOutR0, out float fOutSmoothness, out vec3 vOutBumpNormal, const in C_Intersection intersection )
{
vOutBumpNormal = intersection.vNormal;
if(intersection.fObjectId == 1.0)
{
vec2 vUV = intersection.vUVW.xy * 0.1;
vOutAlbedo = texture(iChannel0, vUV).rgb;
float fBumpScale = 10.0;
vec2 vRes = iChannelResolution[0].xy;
vec2 vDU = vec2(1.0, 0.0) / vRes;
vec2 vDV = vec2(0.0, 1.0) / vRes;
float fSampleW = texture(iChannel0, vUV - vDU).r;
float fSampleE = texture(iChannel0, vUV + vDU).r;
float fSampleN = texture(iChannel0, vUV - vDV).r;
float fSampleS = texture(iChannel0, vUV + vDV).r;
vec3 vNormalDelta = vec3(0.0);
vNormalDelta.x +=
( fSampleW * fSampleW
- fSampleE * fSampleE) * fBumpScale;
vNormalDelta.z +=
(fSampleN * fSampleN
- fSampleS * fSampleS) * fBumpScale;
vOutBumpNormal = normalize(vOutBumpNormal + vNormalDelta);
vOutAlbedo = vOutAlbedo * vOutAlbedo;
fOutSmoothness = clamp((0.8 - vOutAlbedo.r * 4.0), 0.0, 1.0);
vOutR0 = vec3(0.01) * vOutAlbedo.g;
}
else if(intersection.fObjectId == 2.0)
{
vOutAlbedo = vec3(0.5, 0.5, 0.2);
fOutSmoothness = 0.4;
vOutR0 = vec3(0.05);
}
else if(intersection.fObjectId == 3.0)
{
float fAngle = atan(intersection.vUVW.x, intersection.vUVW.z);
vec2 vUV = vec2(fAngle, intersection.vUVW.y) * vec2(1.0, 0.2) * 8.0;
vOutAlbedo = texture(iChannel1, vUV).rgb;
fOutSmoothness = clamp(1.0 - vOutAlbedo.r * vOutAlbedo.r * 2.0, 0.0, 1.0);
vec3 vCol1 = vec3(1.0, 0.5, 0.0);
vec3 vCol2 = vec3(0.5, 0.06, 0.0);
vOutAlbedo = mix(vCol1, vCol2, vOutAlbedo.r * 0.5).rgb;
vOutR0 = vec3(0.05);
}
else if(intersection.fObjectId == 4.0)
{
vOutAlbedo = vec3(1.0, 0.824, 0.301);
fOutSmoothness = 0.4;
vOutR0 = vec3(0.05);
}
}
vec3 GetSkyColour( const in vec3 vDir )
{
vec3 vResult = mix(vec3(0.02, 0.04, 0.06), vec3(0.1, 0.5, 0.8), abs(vDir.y));
return vResult;
}
float GetFogFactor(const in float fDist)
{
float kFogDensity = 0.025;
return exp(fDist * -kFogDensity);
}
vec3 GetFogColour(const in vec3 vDir)
{
return vec3(0.01);
}
vec3 vSunLightColour = vec3(0.1, 0.2, 0.3) * 5.0;
vec3 vSunLightDir = normalize(vec3(0.4, -0.3, -0.5));
void ApplyAtmosphere(inout vec3 vColour, const in float fDist, const in vec3 vRayOrigin, const in vec3 vRayDir)
{
float fFogFactor = GetFogFactor(fDist);
vec3 vFogColour = GetFogColour(vRayDir);
AddDirectionalLightFlareToFog(vFogColour, vRayDir, vSunLightDir, vSunLightColour);
vColour = mix(vFogColour, vColour, fFogFactor);
}
// TRACING LOOP
vec3 GetSceneColour( in vec3 _vRayOrigin, in vec3 _vRayDir )
{
vec3 vRayOrigin = _vRayOrigin;
vec3 vRayDir = _vRayDir;
vec3 vColour = vec3(0.0);
vec3 vRemaining = vec3(1.0);
float fLastShadow = 1.0;
for(int i=0; i<kBounceCount; i++)
{
vec3 vCurrRemaining = vRemaining;
float fShouldApply = 1.0;
C_Intersection intersection;
TraceScene( intersection, vRayOrigin, vRayDir );
vec3 vResult = vec3(0.0);
vec3 vBlendFactor = vec3(0.0);
if(intersection.fObjectId == 0.0)
{
vBlendFactor = vec3(1.0);
fShouldApply = 0.0;
}
else
{
vec3 vAlbedo;
vec3 vR0;
float fSmoothness;
vec3 vBumpNormal;
GetSurfaceInfo( vAlbedo, vR0, fSmoothness, vBumpNormal, intersection );
vec3 vDiffuseLight = vec3(0.0);
vec3 vSpecularLight = vec3(0.0);
fLastShadow = AddDirectionalLight(vDiffuseLight, vSpecularLight, vRayDir, intersection.vPos, vBumpNormal, fSmoothness, vSunLightDir, vSunLightColour);
vec3 vPointLightPos = vLightPos;
#ifdef SCENE_DOMAIN_REPEAT
float fRepeat = 12.0;
float fOffset = (fRepeat * 0.5);
vec2 vTile = floor((intersection.vPos.xz + fOffset) / fRepeat);
vPointLightPos.xz += vTile * fRepeat;
#endif
AddPointLight(vDiffuseLight, vSpecularLight, vRayDir, intersection.vPos, vBumpNormal, fSmoothness, vPointLightPos, vLightColour);
if(intersection.fObjectId >= 3.0)
{
vDiffuseLight += GetSSS(intersection.vPos, vPointLightPos) * vLightColour;
}
else
{
vec3 vToLight = vPointLightPos - intersection.vPos;
float fNdotL = dot(normalize(vToLight), vBumpNormal) * 0.5 + 0.5;
vDiffuseLight += max(0.0, 1.0 - length(vToLight)/5.0) * vLightColour * fNdotL;
}
float fSmoothFactor = fSmoothness * 0.9 + 0.1;
float fFresnelClamp = 0.25; // too much fresnel produces sparkly artefacts
float fNdotD = clamp(dot(vBumpNormal, -vRayDir), fFresnelClamp, 1.0);
vec3 vFresnel = vR0 + (1.0 - vR0) * pow(1.0 - fNdotD, 5.0) * fSmoothFactor;
vResult = mix(vAlbedo * vDiffuseLight, vSpecularLight, vFresnel);
vBlendFactor = vFresnel;
ApplyAtmosphere(vResult, intersection.fDist, vRayOrigin, vRayDir);
vRemaining *= vBlendFactor;
vRayDir = normalize(reflect(vRayDir, vBumpNormal));
vRayOrigin = intersection.vPos;
}
vColour += vResult * vCurrRemaining * fShouldApply;
}
vec3 vSkyColor = GetSkyColour(vRayDir);
ApplyAtmosphere(vSkyColor, kFarClip, vRayOrigin, vRayDir);
// Hack for this scene when using 1 bounce.
// remove final sky reflection when in shadow
vSkyColor *= fLastShadow;
vColour += vSkyColor * vRemaining;
// Face glow
float t = -(_vRayOrigin.z + 2.8) / _vRayDir.z;
if( t > 0.0 )
{
vec3 vPos = _vRayOrigin + _vRayDir * t;
float fDist = abs(GetCarving2dDistance(vPos.xy * vec2(1.0, 1.0)));
float fDot = max(0.0, _vRayDir.z);
fDot = fDot * fDot;
vColour += exp2(-fDist * 10.0) * fDot * vLightColour * 0.25;
}
return vColour;
}
void mainVR( out vec4 fragColor, in vec2 fragCoord, in vec3 fragRayOri, in vec3 fragRayDir )
{
fragRayOri.z = -fragRayOri.z;
fragRayDir.z = -fragRayDir.z;
fragRayOri *= 15.5;
fragRayOri.y += 3.5;
fragRayOri.z -= 8.0;
vec3 vResult = GetSceneColour(fragRayOri, fragRayDir);
vResult = ApplyTonemap(vResult);
vResult = ApplyGamma(vResult);
vResult = ApplyBlackLevel(vResult);
fragColor = vec4( vResult, 1.0 );
}
我尝试使用应用程序 SpriteBatch 将着色器渲染到虚拟 Pixmaptexture，但这导致根本没有渲染任何内容。我还尝试在渲染 UI 之前通过结束和开始 SpriteBatch 来重置 OpenGL 状态。
我已经发现错误了。 首先，在 ShaderToyShader.java 中，我在绑定实际的 ShaderToy 着色器程序之前上传制服并绑定纹理。此外，渲染后我没有从纹理槽中解除纹理绑定。这是 ShaderToyShader.render() 校正后的样子：
public void render() {
shaderToy.bind();
uploadAllUniforms();
fullScreenMesh.render(shaderToy, GL_TRIANGLES);
Gdx.gl.glActiveTexture(GL_TEXTURE0);
Gdx.gl.glBindTexture(GL_TEXTURE_2D, 0);
Gdx.gl.glActiveTexture(1);
Gdx.gl.glBindTexture(GL_TEXTURE_2D, 0);
}
这就是 MenuScreen.render(float delta) 修正后的样子：
@Override
public void render(float delta) {
ScreenUtils.clear(0, 0, 0, 0);
menuBackground.render();
stage.act();
stage.draw();
}
毕竟这只是一个简单的疏忽。