shader uniform

index.ts

@@ -27,8 +27,12 @@ class Renderer{
     gl : WebGL2RenderingContextStrict;
     constructor(gl: WebGL2RenderingContextStrict){
         this.gl = gl;
+    }
+    init(){
+        const gl = this.gl;
+        let program: WebGLProgram;
         try{
-            const program = createProgramFromSource(gl,vert_src,frag_src);
+            program = createProgramFromSource(gl,vert_src,frag_src);
             gl.useProgram(program);
         }
         catch(e){
@@ -40,9 +44,6 @@ class Renderer{
             }
             else throw e;
         }
-    }
-    init(){
-        const gl = this.gl;
         const position = [
             -0.5,-0.5,
             0.5,-0.5,
@@ -61,6 +62,9 @@ class Renderer{
         gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER,indexBuffer);
         gl.bufferData(gl.ELEMENT_ARRAY_BUFFER,new Uint16Array(index),gl.STATIC_DRAW);
 
+        let location = gl.getUniformLocation(program, "u_color"); //u_color 변수 위치를 참조
+        gl.uniform4f(location, 0.8, 0.3, 0.8, 1.0); //해당 위치에 0.2, 0.3, 0.8, 1.0 데이터를 전달
+
     }
     draw(){
         const gl = this.gl;

src/fragment.frag

@@ -1,7 +1,10 @@
 #version 300 es
 precision highp float;
 layout(location=0) out vec4 outColor;
+//in vec4 gl_FragCoord;
+//in vec2 gl_PointCoord;
+uniform vec4 u_color;
 
 void main() {
-  outColor = vec4(0.0,0.0,1.0,1.0);
+  outColor = u_color;
 }