Transformer GL: Simplify GL program handling.

Relanding 9788750ddb, with some changes
applied to improve primarily readability, naming,
and nullness checks.

PiperOrigin-RevId: 406101742

demos/gl/src/main/java/androidx/media3/demo/gl/BitmapOverlayVideoProcessor.java

@@ -15,6 +15,8 @@
  */
 package androidx.media3.demo.gl;
 
+import static androidx.media3.common.util.Assertions.checkNotNull;
+
 import android.content.Context;
 import android.content.pm.PackageManager;
 import android.graphics.Bitmap;
@@ -26,11 +28,11 @@ import android.opengl.GLES20;
 import android.opengl.GLUtils;
 import androidx.annotation.Nullable;
 import androidx.media3.common.C;
-import androidx.media3.common.util.Assertions;
 import androidx.media3.common.util.GlUtil;
 import java.io.IOException;
 import java.util.Locale;
 import javax.microedition.khronos.opengles.GL10;
+import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
 /**
  * Video processor that demonstrates how to overlay a bitmap on video output using a GL shader. The
@@ -49,7 +51,7 @@ import javax.microedition.khronos.opengles.GL10;
   private final Bitmap logoBitmap;
   private final Canvas overlayCanvas;
 
-  private int program;
+  private GlUtil.@MonotonicNonNull Program program;
   @Nullable private GlUtil.Attribute[] attributes;
   @Nullable private GlUtil.Uniform[] uniforms;
 
@@ -77,27 +79,39 @@ import javax.microedition.khronos.opengles.GL10;
 
   @Override
   public void initialize() {
-    String vertexShaderCode;
-    String fragmentShaderCode;
     try {
-      vertexShaderCode = GlUtil.loadAsset(context, "bitmap_overlay_video_processor_vertex.glsl");
+      program =
-      fragmentShaderCode =
+          new GlUtil.Program(
-          GlUtil.loadAsset(context, "bitmap_overlay_video_processor_fragment.glsl");
+              context,
+              /* vertexShaderFilePath= */ "bitmap_overlay_video_processor_vertex.glsl",
+              /* fragmentShaderFilePath= */ "bitmap_overlay_video_processor_fragment.glsl");
     } catch (IOException e) {
       throw new IllegalStateException(e);
     }
-    program = GlUtil.compileProgram(vertexShaderCode, fragmentShaderCode);
+    GlUtil.Attribute[] attributes = program.getAttributes();
-    GlUtil.Attribute[] attributes = GlUtil.getAttributes(program);
-    GlUtil.Uniform[] uniforms = GlUtil.getUniforms(program);
     for (GlUtil.Attribute attribute : attributes) {
       if (attribute.name.equals("a_position")) {
-        attribute.setBuffer(new float[] {-1, -1, 0, 1, 1, -1, 0, 1, -1, 1, 0, 1, 1, 1, 0, 1}, 4);
+        attribute.setBuffer(
+            new float[] {
+              -1, -1, 0, 1,
+              1, -1, 0, 1,
+              -1, 1, 0, 1,
+              1, 1, 0, 1
+            },
+            4);
       } else if (attribute.name.equals("a_texcoord")) {
-        attribute.setBuffer(new float[] {0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1}, 4);
+        attribute.setBuffer(
+            new float[] {
+              0, 0, 0, 1,
+              1, 0, 0, 1,
+              0, 1, 0, 1,
+              1, 1, 0, 1
+            },
+            4);
       }
     }
     this.attributes = attributes;
-    this.uniforms = uniforms;
+    this.uniforms = program.getUniforms();
     GLES20.glGenTextures(1, textures, 0);
     GLES20.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);
     GLES20.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_NEAREST);
@@ -126,9 +140,9 @@ import javax.microedition.khronos.opengles.GL10;
     GlUtil.checkGlError();
 
     // Run the shader program.
-    GlUtil.Uniform[] uniforms = Assertions.checkNotNull(this.uniforms);
+    GlUtil.Uniform[] uniforms = checkNotNull(this.uniforms);
-    GlUtil.Attribute[] attributes = Assertions.checkNotNull(this.attributes);
+    GlUtil.Attribute[] attributes = checkNotNull(this.attributes);
-    GLES20.glUseProgram(program);
+    checkNotNull(program).use();
     for (GlUtil.Uniform uniform : uniforms) {
       switch (uniform.name) {
         case "tex_sampler_0":

libraries/common/src/main/java/androidx/media3/common/util/GlUtil.java

@@ -55,6 +55,160 @@ public final class GlUtil {
   /** Thrown when the required EGL version is not supported by the device. */
   public static final class UnsupportedEglVersionException extends Exception {}
 
+  /** GL program. */
+  public static final class Program {
+    /** The identifier of a compiled and linked GLSL shader program. */
+    private final int programId;
+
+    /**
+     * Compiles a GL shader program from vertex and fragment shader GLSL GLES20 code.
+     *
+     * @param vertexShaderGlsl The vertex shader program.
+     * @param fragmentShaderGlsl The fragment shader program.
+     */
+    public Program(String vertexShaderGlsl, String fragmentShaderGlsl) {
+      programId = GLES20.glCreateProgram();
+      checkGlError();
+
+      // Add the vertex and fragment shaders.
+      addShader(GLES20.GL_VERTEX_SHADER, vertexShaderGlsl);
+      addShader(GLES20.GL_FRAGMENT_SHADER, fragmentShaderGlsl);
+    }
+
+    /**
+     * Compiles a GL shader program from vertex and fragment shader GLSL GLES20 code.
+     *
+     * @param context The {@link Context}.
+     * @param vertexShaderFilePath The path to a vertex shader program.
+     * @param fragmentShaderFilePath The path to a fragment shader program.
+     * @throws IOException When failing to read shader files.
+     */
+    public Program(Context context, String vertexShaderFilePath, String fragmentShaderFilePath)
+        throws IOException {
+      this(loadAsset(context, vertexShaderFilePath), loadAsset(context, fragmentShaderFilePath));
+    }
+
+    /**
+     * Compiles a GL shader program from vertex and fragment shader GLSL GLES20 code.
+     *
+     * @param vertexShaderGlsl The vertex shader program as arrays of strings. Strings are joined by
+     *     adding a new line character in between each of them.
+     * @param fragmentShaderGlsl The fragment shader program as arrays of strings. Strings are
+     *     joined by adding a new line character in between each of them.
+     */
+    public Program(String[] vertexShaderGlsl, String[] fragmentShaderGlsl) {
+      this(TextUtils.join("\n", vertexShaderGlsl), TextUtils.join("\n", fragmentShaderGlsl));
+    }
+
+    /** Uses the program. */
+    public void use() {
+      // Link and check for errors.
+      GLES20.glLinkProgram(programId);
+      int[] linkStatus = new int[] {GLES20.GL_FALSE};
+      GLES20.glGetProgramiv(programId, GLES20.GL_LINK_STATUS, linkStatus, 0);
+      if (linkStatus[0] != GLES20.GL_TRUE) {
+        throwGlException(
+            "Unable to link shader program: \n" + GLES20.glGetProgramInfoLog(programId));
+      }
+      checkGlError();
+
+      GLES20.glUseProgram(programId);
+    }
+
+    /** Deletes the program. Deleted programs cannot be used again. */
+    public void delete() {
+      GLES20.glDeleteProgram(programId);
+    }
+
+    /** Returns the location of an {@link Attribute}. */
+    public int getAttribLocation(String attributeName) {
+      return GLES20.glGetAttribLocation(programId, attributeName);
+    }
+
+    /** Returns the location of a {@link Uniform}. */
+    public int getUniformLocation(String uniformName) {
+      return GLES20.glGetUniformLocation(programId, uniformName);
+    }
+
+    /** Returns the program's {@link Attribute}s. */
+    public Attribute[] getAttributes() {
+      int[] attributeCount = new int[1];
+      GLES20.glGetProgramiv(programId, GLES20.GL_ACTIVE_ATTRIBUTES, attributeCount, 0);
+      if (attributeCount[0] != 2) {
+        throw new IllegalStateException("Expected two attributes.");
+      }
+
+      Attribute[] attributes = new Attribute[attributeCount[0]];
+      for (int i = 0; i < attributeCount[0]; i++) {
+        attributes[i] = createAttribute(i);
+      }
+      return attributes;
+    }
+
+    /** Returns the program's {@link Uniform}s. */
+    public Uniform[] getUniforms() {
+      int[] uniformCount = new int[1];
+      GLES20.glGetProgramiv(programId, GLES20.GL_ACTIVE_UNIFORMS, uniformCount, 0);
+
+      Uniform[] uniforms = new Uniform[uniformCount[0]];
+      for (int i = 0; i < uniformCount[0]; i++) {
+        uniforms[i] = createUniform(i);
+      }
+
+      return uniforms;
+    }
+
+    private Attribute createAttribute(int index) {
+      int[] length = new int[1];
+      GLES20.glGetProgramiv(programId, GLES20.GL_ACTIVE_ATTRIBUTE_MAX_LENGTH, length, 0);
+
+      int[] type = new int[1];
+      int[] size = new int[1];
+      byte[] nameBytes = new byte[length[0]];
+      int[] ignore = new int[1];
+
+      GLES20.glGetActiveAttrib(
+          programId, index, length[0], ignore, 0, size, 0, type, 0, nameBytes, 0);
+      String name = new String(nameBytes, 0, strlen(nameBytes));
+      int location = getAttribLocation(name);
+
+      return new Attribute(name, index, location);
+    }
+
+    private Uniform createUniform(int index) {
+      int[] length = new int[1];
+      GLES20.glGetProgramiv(programId, GLES20.GL_ACTIVE_UNIFORM_MAX_LENGTH, length, 0);
+
+      int[] type = new int[1];
+      int[] size = new int[1];
+      byte[] nameBytes = new byte[length[0]];
+      int[] ignore = new int[1];
+
+      GLES20.glGetActiveUniform(
+          programId, index, length[0], ignore, 0, size, 0, type, 0, nameBytes, 0);
+      String name = new String(nameBytes, 0, strlen(nameBytes));
+      int location = getUniformLocation(name);
+
+      return new Uniform(name, location, type[0]);
+    }
+
+    private void addShader(int type, String glsl) {
+      int shader = GLES20.glCreateShader(type);
+      GLES20.glShaderSource(shader, glsl);
+      GLES20.glCompileShader(shader);
+
+      int[] result = new int[] {GLES20.GL_FALSE};
+      GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, result, 0);
+      if (result[0] != GLES20.GL_TRUE) {
+        throwGlException(GLES20.glGetShaderInfoLog(shader) + ", source: " + glsl);
+      }
+
+      GLES20.glAttachShader(programId, shader);
+      GLES20.glDeleteShader(shader);
+      checkGlError();
+    }
+  }
+
   /**
    * GL attribute, which can be attached to a buffer with {@link Attribute#setBuffer(float[], int)}.
    */
@@ -69,26 +223,11 @@ public final class GlUtil {
     @Nullable private Buffer buffer;
     private int size;
 
-    /**
+    /* Creates a new Attribute. */
-     * Creates a new GL attribute.
+    public Attribute(String name, int index, int location) {
-     *
+      this.name = name;
-     * @param program The identifier of a compiled and linked GLSL shader program.
-     * @param index The index of the attribute. After this instance has been constructed, the name
-     *     of the attribute is available via the {@link #name} field.
-     */
-    public Attribute(int program, int index) {
-      int[] len = new int[1];
-      GLES20.glGetProgramiv(program, GLES20.GL_ACTIVE_ATTRIBUTE_MAX_LENGTH, len, 0);
-
-      int[] type = new int[1];
-      int[] size = new int[1];
-      byte[] nameBytes = new byte[len[0]];
-      int[] ignore = new int[1];
-
-      GLES20.glGetActiveAttrib(program, index, len[0], ignore, 0, size, 0, type, 0, nameBytes, 0);
-      name = new String(nameBytes, 0, strlen(nameBytes));
-      location = GLES20.glGetAttribLocation(program, name);
       this.index = index;
+      this.location = location;
     }
 
     /**
@@ -138,28 +277,12 @@ public final class GlUtil {
     private int texId;
     private int unit;
 
-    /**
+    /** Creates a new uniform. */
-     * Creates a new GL uniform.
+    public Uniform(String name, int location, int type) {
-     *
+      this.name = name;
-     * @param program The identifier of a compiled and linked GLSL shader program.
+      this.location = location;
-     * @param index The index of the uniform. After this instance has been constructed, the name of
+      this.type = type;
-     *     the uniform is available via the {@link #name} field.
+      this.value = new float[16];
-     */
-    public Uniform(int program, int index) {
-      int[] len = new int[1];
-      GLES20.glGetProgramiv(program, GLES20.GL_ACTIVE_UNIFORM_MAX_LENGTH, len, 0);
-
-      int[] type = new int[1];
-      int[] size = new int[1];
-      byte[] name = new byte[len[0]];
-      int[] ignore = new int[1];
-
-      GLES20.glGetActiveUniform(program, index, len[0], ignore, 0, size, 0, type, 0, name, 0);
-      this.name = new String(name, 0, strlen(name));
-      location = GLES20.glGetUniformLocation(program, this.name);
-      this.type = type[0];
-
-      value = new float[16];
     }
 
     /**
@@ -333,74 +456,6 @@ public final class GlUtil {
     Api17.focusSurface(eglDisplay, eglContext, surface, width, height);
   }
 
-  /**
-   * Builds a GL shader program from vertex and fragment shader code.
-   *
-   * @param vertexCode GLES20 vertex shader program as arrays of strings. Strings are joined by
-   *     adding a new line character in between each of them.
-   * @param fragmentCode GLES20 fragment shader program as arrays of strings. Strings are joined by
-   *     adding a new line character in between each of them.
-   * @return GLES20 program id.
-   */
-  public static int compileProgram(String[] vertexCode, String[] fragmentCode) {
-    return compileProgram(TextUtils.join("\n", vertexCode), TextUtils.join("\n", fragmentCode));
-  }
-
-  /**
-   * Builds a GL shader program from vertex and fragment shader code.
-   *
-   * @param vertexCode GLES20 vertex shader program.
-   * @param fragmentCode GLES20 fragment shader program.
-   * @return GLES20 program id.
-   */
-  public static int compileProgram(String vertexCode, String fragmentCode) {
-    int program = GLES20.glCreateProgram();
-    checkGlError();
-
-    // Add the vertex and fragment shaders.
-    addShader(GLES20.GL_VERTEX_SHADER, vertexCode, program);
-    addShader(GLES20.GL_FRAGMENT_SHADER, fragmentCode, program);
-
-    // Link and check for errors.
-    GLES20.glLinkProgram(program);
-    int[] linkStatus = new int[] {GLES20.GL_FALSE};
-    GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
-    if (linkStatus[0] != GLES20.GL_TRUE) {
-      throwGlException("Unable to link shader program: \n" + GLES20.glGetProgramInfoLog(program));
-    }
-    checkGlError();
-
-    return program;
-  }
-
-  /** Returns the {@link Attribute}s in the specified {@code program}. */
-  public static Attribute[] getAttributes(int program) {
-    int[] attributeCount = new int[1];
-    GLES20.glGetProgramiv(program, GLES20.GL_ACTIVE_ATTRIBUTES, attributeCount, 0);
-    if (attributeCount[0] != 2) {
-      throw new IllegalStateException("Expected two attributes.");
-    }
-
-    Attribute[] attributes = new Attribute[attributeCount[0]];
-    for (int i = 0; i < attributeCount[0]; i++) {
-      attributes[i] = new Attribute(program, i);
-    }
-    return attributes;
-  }
-
-  /** Returns the {@link Uniform}s in the specified {@code program}. */
-  public static Uniform[] getUniforms(int program) {
-    int[] uniformCount = new int[1];
-    GLES20.glGetProgramiv(program, GLES20.GL_ACTIVE_UNIFORMS, uniformCount, 0);
-
-    Uniform[] uniforms = new Uniform[uniformCount[0]];
-    for (int i = 0; i < uniformCount[0]; i++) {
-      uniforms[i] = new Uniform(program, i);
-    }
-
-    return uniforms;
-  }
-
   /**
    * Deletes a GL texture.
    *
@@ -479,22 +534,6 @@ public final class GlUtil {
     return texId[0];
   }
 
-  private static void addShader(int type, String source, int program) {
-    int shader = GLES20.glCreateShader(type);
-    GLES20.glShaderSource(shader, source);
-    GLES20.glCompileShader(shader);
-
-    int[] result = new int[] {GLES20.GL_FALSE};
-    GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, result, 0);
-    if (result[0] != GLES20.GL_TRUE) {
-      throwGlException(GLES20.glGetShaderInfoLog(shader) + ", source: " + source);
-    }
-
-    GLES20.glAttachShader(program, shader);
-    GLES20.glDeleteShader(shader);
-    checkGlError();
-  }
-
   private static void throwGlException(String errorMsg) {
     Log.e(TAG, errorMsg);
     if (glAssertionsEnabled) {

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/video/VideoDecoderGLSurfaceView.java

@@ -15,6 +15,8 @@
  */
 package androidx.media3.exoplayer.video;
 
+import static androidx.media3.common.util.Assertions.checkNotNull;
+
 import android.content.Context;
 import android.opengl.GLES20;
 import android.opengl.GLSurfaceView;
@@ -31,6 +33,7 @@ import javax.microedition.khronos.egl.EGLConfig;
 import javax.microedition.khronos.opengles.GL10;
 import org.checkerframework.checker.nullness.compatqual.NullableType;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
+import org.checkerframework.checker.nullness.qual.RequiresNonNull;
 
 /**
  * GLSurfaceView implementing {@link VideoDecoderOutputBufferRenderer} for rendering {@link
@@ -143,7 +146,7 @@ public final class VideoDecoderGLSurfaceView extends GLSurfaceView
     // glDrawArrays uses it.
     private final FloatBuffer[] textureCoords;
 
-    private int program;
+    private GlUtil.@MonotonicNonNull Program program;
     private int colorMatrixLocation;
 
     // Accessed only from the GL thread.
@@ -164,9 +167,9 @@ public final class VideoDecoderGLSurfaceView extends GLSurfaceView
 
     @Override
     public void onSurfaceCreated(GL10 unused, EGLConfig config) {
-      program = GlUtil.compileProgram(VERTEX_SHADER, FRAGMENT_SHADER);
+      program = new GlUtil.Program(VERTEX_SHADER, FRAGMENT_SHADER);
-      GLES20.glUseProgram(program);
+      program.use();
-      int posLocation = GLES20.glGetAttribLocation(program, "in_pos");
+      int posLocation = program.getAttribLocation("in_pos");
       GLES20.glEnableVertexAttribArray(posLocation);
       GLES20.glVertexAttribPointer(
           posLocation,
@@ -175,14 +178,14 @@ public final class VideoDecoderGLSurfaceView extends GLSurfaceView
           /* normalized= */ false,
           /* stride= */ 0,
           TEXTURE_VERTICES);
-      texLocations[0] = GLES20.glGetAttribLocation(program, "in_tc_y");
+      texLocations[0] = program.getAttribLocation("in_tc_y");
       GLES20.glEnableVertexAttribArray(texLocations[0]);
-      texLocations[1] = GLES20.glGetAttribLocation(program, "in_tc_u");
+      texLocations[1] = program.getAttribLocation("in_tc_u");
       GLES20.glEnableVertexAttribArray(texLocations[1]);
-      texLocations[2] = GLES20.glGetAttribLocation(program, "in_tc_v");
+      texLocations[2] = program.getAttribLocation("in_tc_v");
       GLES20.glEnableVertexAttribArray(texLocations[2]);
       GlUtil.checkGlError();
-      colorMatrixLocation = GLES20.glGetUniformLocation(program, "mColorConversion");
+      colorMatrixLocation = program.getUniformLocation("mColorConversion");
       GlUtil.checkGlError();
       setupTextures();
       GlUtil.checkGlError();
@@ -209,7 +212,7 @@ public final class VideoDecoderGLSurfaceView extends GLSurfaceView
         renderedOutputBuffer = pendingOutputBuffer;
       }
 
-      VideoDecoderOutputBuffer outputBuffer = Assertions.checkNotNull(renderedOutputBuffer);
+      VideoDecoderOutputBuffer outputBuffer = checkNotNull(renderedOutputBuffer);
 
       // Set color matrix. Assume BT709 if the color space is unknown.
       float[] colorConversion = kColorConversion709;
@@ -232,8 +235,8 @@ public final class VideoDecoderGLSurfaceView extends GLSurfaceView
           colorConversion,
           /* offset= */ 0);
 
-      int[] yuvStrides = Assertions.checkNotNull(outputBuffer.yuvStrides);
+      int[] yuvStrides = checkNotNull(outputBuffer.yuvStrides);
-      ByteBuffer[] yuvPlanes = Assertions.checkNotNull(outputBuffer.yuvPlanes);
+      ByteBuffer[] yuvPlanes = checkNotNull(outputBuffer.yuvPlanes);
 
       for (int i = 0; i < 3; i++) {
         int h = (i == 0) ? outputBuffer.height : (outputBuffer.height + 1) / 2;
@@ -296,10 +299,11 @@ public final class VideoDecoderGLSurfaceView extends GLSurfaceView
       surfaceView.requestRender();
     }
 
+    @RequiresNonNull("program")
     private void setupTextures() {
       GLES20.glGenTextures(3, yuvTextures, /* offset= */ 0);
       for (int i = 0; i < 3; i++) {
-        GLES20.glUniform1i(GLES20.glGetUniformLocation(program, TEXTURE_UNIFORMS[i]), i);
+        GLES20.glUniform1i(program.getUniformLocation(TEXTURE_UNIFORMS[i]), i);
         GLES20.glActiveTexture(GLES20.GL_TEXTURE0 + i);
         GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, yuvTextures[i]);
         GLES20.glTexParameterf(

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/video/spherical/ProjectionRenderer.java

@@ -15,6 +15,7 @@
  */
 package androidx.media3.exoplayer.video.spherical;
 
+import static androidx.media3.common.util.Assertions.checkNotNull;
 import static androidx.media3.common.util.GlUtil.checkGlError;
 
 import android.opengl.GLES11Ext;
@@ -92,9 +93,9 @@ import java.nio.FloatBuffer;
   private int stereoMode;
   @Nullable private MeshData leftMeshData;
   @Nullable private MeshData rightMeshData;
+  @Nullable private GlUtil.Program program;
 
-  // Program related GL items. These are only valid if program != 0.
+  // Program related GL items. These are only valid if program is non-null.
-  private int program;
   private int mvpMatrixHandle;
   private int uTexMatrixHandle;
   private int positionHandle;
@@ -119,12 +120,12 @@ import java.nio.FloatBuffer;
 
   /** Initializes of the GL components. */
   /* package */ void init() {
-    program = GlUtil.compileProgram(VERTEX_SHADER_CODE, FRAGMENT_SHADER_CODE);
+    program = new GlUtil.Program(VERTEX_SHADER_CODE, FRAGMENT_SHADER_CODE);
-    mvpMatrixHandle = GLES20.glGetUniformLocation(program, "uMvpMatrix");
+    mvpMatrixHandle = program.getUniformLocation("uMvpMatrix");
-    uTexMatrixHandle = GLES20.glGetUniformLocation(program, "uTexMatrix");
+    uTexMatrixHandle = program.getUniformLocation("uTexMatrix");
-    positionHandle = GLES20.glGetAttribLocation(program, "aPosition");
+    positionHandle = program.getAttribLocation("aPosition");
-    texCoordsHandle = GLES20.glGetAttribLocation(program, "aTexCoords");
+    texCoordsHandle = program.getAttribLocation("aTexCoords");
-    textureHandle = GLES20.glGetUniformLocation(program, "uTexture");
+    textureHandle = program.getUniformLocation("uTexture");
   }
 
   /**
@@ -143,7 +144,7 @@ import java.nio.FloatBuffer;
     }
 
     // Configure shader.
-    GLES20.glUseProgram(program);
+    checkNotNull(program).use();
     checkGlError();
 
     GLES20.glEnableVertexAttribArray(positionHandle);
@@ -196,8 +197,9 @@ import java.nio.FloatBuffer;
 
   /** Cleans up the GL resources. */
   /* package */ void shutdown() {
-    if (program != 0) {
+    if (program != null) {
-      GLES20.glDeleteProgram(program);
+      program.delete();
+      program = null;
     }
   }
 

libraries/transformer/src/main/java/androidx/media3/transformer/TransformerTranscodingVideoRenderer.java

@@ -229,17 +229,19 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
     GlUtil.focusSurface(
         eglDisplay, eglContext, eglSurface, decoderInputFormat.width, decoderInputFormat.height);
     decoderTextureId = GlUtil.createExternalTexture();
-    String vertexShaderCode;
+    GlUtil.Program copyProgram;
-    String fragmentShaderCode;
     try {
-      vertexShaderCode = GlUtil.loadAsset(context, "shaders/blit_vertex_shader.glsl");
+      copyProgram =
-      fragmentShaderCode = GlUtil.loadAsset(context, "shaders/copy_external_fragment_shader.glsl");
+          new GlUtil.Program(
+              context,
+              /* vertexShaderFilePath= */ "shaders/blit_vertex_shader.glsl",
+              /* fragmentShaderFilePath= */ "shaders/copy_external_fragment_shader.glsl");
     } catch (IOException e) {
       throw new IllegalStateException(e);
     }
-    int copyProgram = GlUtil.compileProgram(vertexShaderCode, fragmentShaderCode);
+
-    GLES20.glUseProgram(copyProgram);
+    copyProgram.use();
-    GlUtil.Attribute[] copyAttributes = GlUtil.getAttributes(copyProgram);
+    GlUtil.Attribute[] copyAttributes = copyProgram.getAttributes();
     checkState(copyAttributes.length == 2, "Expected program to have two vertex attributes.");
     for (GlUtil.Attribute copyAttribute : copyAttributes) {
       if (copyAttribute.name.equals("a_position")) {
@@ -265,7 +267,7 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
       }
       copyAttribute.bind();
     }
-    GlUtil.Uniform[] copyUniforms = GlUtil.getUniforms(copyProgram);
+    GlUtil.Uniform[] copyUniforms = copyProgram.getUniforms();
     checkState(copyUniforms.length == 2, "Expected program to have two uniforms.");
     for (GlUtil.Uniform copyUniform : copyUniforms) {
       if (copyUniform.name.equals("tex_sampler")) {