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How to use a shader for color lines drawn with GL_LINES and OpenGL ES 2.0

I have an Android application using OpenGL ES 2.0. I need to draw 10 lines from an array, each of which is described by a start point and an end point. Thus, there are 10 rows = 20 points = 60 float values. None of the points are connected, so each pair of points in the array is not connected with the rest, so I draw with GL_LINES.

I draw them by putting values ​​in a floating-point buffer and calling some helper code as follows:

public void drawLines(FloatBuffer vertexBuffer, float lineWidth,
        int numPoints, float colour[]) {
    GLES20.glLineWidth(lineWidth);
    drawShape(vertexBuffer, GLES20.GL_LINES, numPoints, colour);
}

protected void drawShape(FloatBuffer vertexBuffer, int drawType,
        int numPoints, float colour[]) {
    // ... set shader ...
    GLES20.glDrawArrays(drawType, 0, numPoints);
}

DrawLines accepts a float buffer (60 floats), line width, number of dots (20) and 4 float color arrays. I did not show the shader setup code, but it basically provides the color variable with a uniform uColour value.

, uColour, .

/* Fragment */
precision mediump float;

uniform vec4 uColour;
uniform float uTime;

void main() {
    gl_FragColor = uColour;
}

:

uniform mat4 uMVPMatrix;

attribute vec4 vPosition;

void main() {
    gl_Position = uMVPMatrix * vPosition;
}

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, uColour , . GL 10 , .

, , uVertexCount, ? uVertexCount 0, , , . , uVertexCount. . , .

? , . , , 0, 1, * , 2, 3, * ..

- - , - ?

+5
1

Vertexbuffer (Floatbuffer) .

vertexbuffer:

uniform mat4 uMVPMatrix;

attribute vec4 vPosition;
attribute vec3 vColor;

varying vec3 color;

void main() {
    gl_Position = uMVPMatrix * vPosition;
    color = vColor;
}

fragmentshader:

precision mediump float;

varying vec3 color;

void main() {
    gl_FragColor = color;
}
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