Android OpenGL ES详解——绘制圆角矩形

1、绘制矩形

代码如下：

renderer类：

package com.example.roundrectimport android.content.Context
import android.opengl.GLES30
import android.opengl.GLSurfaceView.Renderer
import com.opengllib.data.VertexArray
import com.opengllib.programs.ShaderProgram
import javax.microedition.khronos.egl.EGLConfig
import javax.microedition.khronos.opengles.GL10class RoundRectRenderer(context: Context) : Renderer {private var mVertices = floatArrayOf(-0.5f, -0.5f,0.5f, 0.5f,-0.5f, 0.5f,-0.5f, -0.5f,0.5f, -0.5f,0.5f, 0.5f,)private var mShaderProgram: ShaderProgram? = nullprivate var mContext = contextprivate var mVertexArray: VertexArray? = nulloverride fun onSurfaceCreated(gl: GL10?, config: EGLConfig?) {GLES30.glClearColor(0.6f, 0.7f, 0.8f, 1.0f)mVertexArray = VertexArray(mVertices)mShaderProgram = ShaderProgram(mContext,R.raw.roundrect_vertex_shader,R.raw.roundrect_fragment_shader)mShaderProgram?.useProgram()mVertexArray?.setVertexAttribPointer(0,mShaderProgram?.getPositionAttributeLocation()!!,2,0)}override fun onSurfaceChanged(gl: GL10?, width: Int, height: Int) {GLES30.glViewport(0, 0, width, height)}override fun onDrawFrame(gl: GL10?) {GLES30.glClear(GLES30.GL_COLOR_BUFFER_BIT)GLES30.glDrawArrays(GLES30.GL_TRIANGLES,0 ,mVertices.size / 2)}
}

顶点着色器文件roundrect_vertex_shader.glsl代码如下：

attribute vec4 a_Position;void main()
{gl_Position = a_Position;
}

片元着色器文件roundrect_fragment_shader.glsl代码如下：

precision mediump float;void main()
{gl_FragColor = vec4(0.8, 0.5, 0.3, 1.0);
}

2、绘制圆形

3、绘制圆角矩形

参考文章

使用OpenGL实现圆角效果-腾讯云开发者社区-腾讯云