将精灵色变白

Question

我试图改变雪碧的颜色(红色和灰色)，白色。

sprite.setColor(1, 1, 1, 1);

但什么都没发生。

我怎样才能改变所有雪碧的白色颜色？

Answer 1

如果您想要将雪碧中所有形状的颜色更改为白色，那么唯一可以做到的方法是使用像素着色器，并将它们不是黑色的所有片段(我假设在您的游戏中以黑体呈现)设置为白色。就像这样：

varying vec4 v_color;
varying vec2 v_texCoords;
uniform sampler2D u_texture;
void main() {
    vec4 color=v_color * texture2D(u_texture, v_texCoords);

    if(color.r!=0 && color.g!=0 && color.b!=0){
        gl_FragColor=vec4(1,1,1,1);
    }
    else{
        gl_FragColor=color;
    }
}

如果您是不幸的，并且您使用了OpenGLE1.0(固定管道)，我建议您切换到gles 2.0，因为您是一个来自90‘的beginer.Fixed管道，我们在2013年！

守则：

初始化

  ShaderProgram.pedantic = false;

  ShaderProgram defaultShader=SpriteBatch.createDefaultShader();

  ShaderProgram shaderWhiteTexture=new ShaderProgram(Gdx.files.internal("vertexShader.vs").readString(),Gdx.files.internal("fragShader.fs").readString());

渲染

//Render the textures with the normal colors 
spriteBatch.begin();
spriteBatch.draw(sprite1,sprite2,sprite3...);//or whatever code u use to render them
spriteBatch.end();

//Render the textures with the shader
spriteBatch.setShader(shaderWhiteTexture);
spriteBatch.begin();
spriteBatch.draw(sprite4,sprite5,sprite6...);//or whatever code u use to render them
spriteBatch.end();
spriteBatch.setShader(defaultShader);

阴影

//vertexShader.vs:
attribute highp vec4 a_position;
attribute highp vec4 a_color;
attribute highp vec2 a_texCoord0;
uniform mat4 u_projTrans;

varying highp vec4 v_color;
varying highp vec2 v_texCoords;

void main() {
    v_color = a_color;
    v_texCoords = a_texCoord0;
    gl_Position = u_projTrans * a_position ;
}

//fragShader.fs:
varying highp vec4 v_color;
varying highp vec2 v_texCoords;
uniform sampler2D u_texture;
void main() {

    gl_FragColor = vec4(0.0);

    highp vec4 color = texture2D(u_texture, v_texCoords);

    if(color.a > 0.0) {
       gl_FragColor = vec4(1.0,0,0,1.0);
}

}

由问题所有者编辑的 :现在使用透明纹理

添加了什么?：

1 . the highp precision to variables
2 . the fragmentShader file Main() fonction edited

Answer 2

那不管用。白色不会影响更深的颜色(读:其他颜色)。

这实际上是sprite的默认设置，因此它的呈现与您创建它的映像完全相同(这就是您没有看到更改的原因)。如果要使用雪碧颜色影响雪碧在运行时的呈现方式，请考虑将其变为白色，然后将其更改为任何其他颜色。

Answer 3

您可以通过使用模具缓冲区来实现这一点，而无需任何OpenGL2函数或着色器，也不需要雪碧的预白副本或任何其他疯狂的东西。

首先将您的sprite绘制到模具缓冲区，然后在模具上绘制一个颜色适当的矩形，它将只绘制模板所在的位置，留下一个彩色剪影。

以下是它的工作原理：

//Turn off drawing to the color buffers
Gdx.gl.glColorMask(false, false, false, false);

//Enable drawing to the stencil buffer
Gdx.gl.glEnable(GL10.GL_STENCIL_TEST);

//Set the stencil mask you want to use, mask 1 is as good as any other
Gdx.gl.glStencilMask(1);

//When drawing, Always attempt to draw a 1 into mask 1 for every pixel
Gdx.gl.glStencilFunc(GL10.GL_ALWAYS, 1, 1);
//When drawing, replace whatever is currently in the mask
Gdx.gl.glStencilOp(GL10.GL_REPLACE, GL10.GL_REPLACE, GL10.GL_REPLACE);

//unlike the name would have you believe, this call actually sets the 'color'
//to clear the stencil with and doesnt actually clear the stencil. We want to
//set the mask to all 0's
Gdx.gl.glClearStencil(0); 
//This then clears the stencil buffer with all 0's
Gdx.gl.glClear(GL10.GL_STENCIL_BUFFER_BIT);

//A sprite typically has transparent pixels, and we don't want to draw them
//into the mask, so filter out pixels with an alpha less than 0.5f. Only
//those greater are drawn into the stencil buffer
Gdx.gl.glEnable(GL10.GL_ALPHA_TEST);
Gdx.gl10.glAlphaFunc(GL10.GL_GREATER, 0.5f);

//Draw the sprite into the stencil buffer
spriteBatch.begin();
spriteBatch.draw(...)
spriteBatch.end();

//Finished filtering the alpha channel
Gdx.gl.glDisable(GL10.GL_ALPHA_TEST);

//Now that we want to use the mask instead of drawing into it so we turn
//drawing to the color buffer back on
Gdx.gl.glColorMask(true, true, true, true);
//Set us up to only draw where the stencil buffer equals 1
Gdx.gl.glStencilFunc(GL10.GL_EQUAL, 1, 1);
//And since drawing into the mask is actually still on, we set this to keep the
//values in the stencil buffer, and not overwrite them
Gdx.gl.glStencilOp(GL10.GL_KEEP, GL10.GL_KEEP, GL10.GL_KEEP);

//Draw a coloured rectangle over the mask, and it will only draw pixels where the
//stencil buffer has been set giving you a silhoutte of your sprite! You can also
//use a transparent rect and draw over a normal render of your sprite to fade the
//sprite up into whatever color you want
shapeRenderer.begin(ShapeType.Fill);
shapeRenderer.rect(...);
shapeRenderer.end();

//Done with the stencil
Gdx.gl.glDisable(GL10.GL_STENCIL_TEST);