Const vertexShaderText
vertexShaderText: "precision mediump float;attribute vec2 position;attribute float value;uniform sampler2D colorScale;uniform vec4 extent;uniform float fillValue;uniform vec2 delta;varying vec4 color;varying float skip;void main(){if(value == fillValue) {color = vec4(0.0, 0.0, 0.0, 0.0);skip = 1.0;}else {color = texture2D(colorScale, vec2(value, 0.5));skip = 0.0;}gl_Position = vec4(((position.x-extent.x) / delta.x) * 2.0 - 1.0,((position.y-extent.w) / delta.y) * -2.0 + 1.0,0.0, 1.0);}" = `precision mediump float;attribute vec2 position;attribute float value;uniform sampler2D colorScale;uniform vec4 extent;uniform float fillValue;uniform vec2 delta;varying vec4 color;varying float skip;void main(){if(value == fillValue) {color = vec4(0.0, 0.0, 0.0, 0.0);skip = 1.0;}else {color = texture2D(colorScale, vec2(value, 0.5));skip = 0.0;}gl_Position = vec4(((position.x-extent.x) / delta.x) * 2.0 - 1.0,((position.y-extent.w) / delta.y) * -2.0 + 1.0,0.0, 1.0);}`