Question

我正优化一个双向的游戏, iPhone 和 Android。我用4个阴影来绘制场景, 我注意到如果我把其中一个变换成另一个, 纤维灯泡会从32个增加到42个, 即使只有1个符号是用这个阴影画的, 而这2个阴影的唯一区别就是碎片阴影里的一个产品。

这些是遮蔽者,

默认 2d- tex. shader

#ifdef GL_ES
precision highp float;
precision lowp int;
#endif

#ifdef VERTEX

uniform mat4        umvp;

attribute vec4      avertex;
attribute vec2      auv;

varying vec2        vuv;

void main()
{
    // Pass the texture coordinate attribute to a varying.
    vuv = auv;

    // Here we set the final position to this vertex.
    gl_Position = umvp * avertex;
}

#endif

#ifdef FRAGMENT

uniform sampler2D   map0;
uniform vec4 ucolor;

varying vec2        vuv;

void main()
{
    gl_FragColor =  texture2D(map0, vuv) * ucolor;
}

#endif

默认 2d- tex- white. shader

#ifdef GL_ES
precision highp float;
precision lowp int;
#endif

#ifdef VERTEX

uniform mat4        umvp;

attribute vec4      avertex;
attribute vec2      auv;

varying vec2        vuv;

void main()
{
    // Pass the texture coordinate attribute to a varying.
    vuv = auv;

    // Here we set the final position to this vertex.
    gl_Position = umvp * avertex;
}

#endif

#ifdef FRAGMENT

uniform sampler2D   map0;

varying vec2        vuv;

void main()
{
    gl_FragColor =  texture2D(map0, vuv);
}

#endif

Again,
If I modify 默认 2d- tex. shader and remove the product "* ucolor", the fps goes from 32 to 42, and I m using it for just one sprite in the scene!

这正常吗?为什么这个遮光剂这么慢,我怎么才能改进它呢?

<强度 > EDIT:

我看到iPod和Android的性能减慢,比例相等。两者均为PowerVr SGX GPUs(iPod 3 gen和三星银河SL-PowerVR SGX 530-),iOS版本为4.1,Android版本为2.3.3。

绘图图I m 缩放以填充屏幕( 缩放为 4x), 我绘制每框架一次。它取自质地图, 因此纹理实际上更大( 1024x1024), 但所拍摄的部分为 80x120 。启用了 Alpha 混合。

<强 > EDIT 2

I made a mistake. The sprite is scaled 11x: its 32x48. If I don t draw that sprite at all, fps goes to 45. I m drawing a lot of sprites in the scene, why is that one taking so much time? Could it be because it s scaled so much?

Answer 1

当你从上述代码中删除“*ucolor”时,

uniform ucolor becomes unused
GLSL compiler removes this uniform from the active uniforms set
when you have you program linked the ID of the missing uniform becomes -1
when you do glUniform4fv( -1, value ) for the removed uniform it just exits instantly, without any update

与“* ucolor”的设置相比,这项工作要少得多。

此外,这是在碎片阴影器中每个碎片少一个操作。

Answer 2

Your problem is in your fragment shader in default-2d-tex.shader. You have uniform vec4 ucolor; That means, that each of your color s components (RGBA) will be converted to 32-bits float value. And this drops performance heavily. Should be: uniform lowp vec4 ucolor;

友情链接