Android: Add helper class for generating OpenGL shaders
This CL adds a helper class GlShaderBuilder to build an instances of
RendererCommon.GlDrawer that can accept multiple input sources
(OES, RGB, or YUV) using a generic fragment shader as input.
Bug: webrtc:9355
Change-Id: I14a0a280d2b6f838984f7b60897cc0c58e2a948a
Reviewed-on: https://webrtc-review.googlesource.com/80940
Commit-Queue: Magnus Jedvert <magjed@webrtc.org>
Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23622}diff --git a/sdk/android/api/org/webrtc/GlRectDrawer.java b/sdk/android/api/org/webrtc/GlRectDrawer.java
index 44787f7..d1fbd1b 100644
--- a/sdk/android/api/org/webrtc/GlRectDrawer.java
+++ b/sdk/android/api/org/webrtc/GlRectDrawer.java
@@ -10,201 +10,22 @@
package org.webrtc;
-import android.opengl.GLES11Ext;
-import android.opengl.GLES20;
-import java.nio.FloatBuffer;
-import java.util.IdentityHashMap;
-import java.util.Map;
-
-/**
- * Helper class to draw an opaque quad on the target viewport location. Rotation, mirror, and
- * cropping is specified using a 4x4 texture coordinate transform matrix. The frame input can either
- * be an OES texture or YUV textures in I420 format. The GL state must be preserved between draw
- * calls, this is intentional to maximize performance. The function release() must be called
- * manually to free the resources held by this object.
- */
-public class GlRectDrawer implements RendererCommon.GlDrawer {
- // clang-format off
- // Simple vertex shader, used for both YUV and OES.
- private static final String VERTEX_SHADER_STRING =
- "varying vec2 interp_tc;\n"
- + "attribute vec4 in_pos;\n"
- + "attribute vec4 in_tc;\n"
- + "\n"
- + "uniform mat4 texMatrix;\n"
- + "\n"
- + "void main() {\n"
- + " gl_Position = in_pos;\n"
- + " interp_tc = (texMatrix * in_tc).xy;\n"
+/** Simplest possible GL shader that just draws frames as opaque quads. */
+public class GlRectDrawer extends GlGenericDrawer {
+ private static final String FRAGMENT_SHADER = "void main() {\n"
+ + " gl_FragColor = sample(tc);\n"
+ "}\n";
- private static final String YUV_FRAGMENT_SHADER_STRING =
- "precision mediump float;\n"
- + "varying vec2 interp_tc;\n"
- + "\n"
- + "uniform sampler2D y_tex;\n"
- + "uniform sampler2D u_tex;\n"
- + "uniform sampler2D v_tex;\n"
- + "\n"
- + "void main() {\n"
- // CSC according to http://www.fourcc.org/fccyvrgb.php
- + " float y = texture2D(y_tex, interp_tc).r;\n"
- + " float u = texture2D(u_tex, interp_tc).r - 0.5;\n"
- + " float v = texture2D(v_tex, interp_tc).r - 0.5;\n"
- + " gl_FragColor = vec4(y + 1.403 * v, "
- + " y - 0.344 * u - 0.714 * v, "
- + " y + 1.77 * u, 1);\n"
- + "}\n";
+ private static class ShaderCallbacks implements GlGenericDrawer.ShaderCallbacks {
+ @Override
+ public void onNewShader(GlShader shader) {}
- private static final String RGB_FRAGMENT_SHADER_STRING =
- "precision mediump float;\n"
- + "varying vec2 interp_tc;\n"
- + "\n"
- + "uniform sampler2D rgb_tex;\n"
- + "\n"
- + "void main() {\n"
- + " gl_FragColor = texture2D(rgb_tex, interp_tc);\n"
- + "}\n";
-
- private static final String OES_FRAGMENT_SHADER_STRING =
- "#extension GL_OES_EGL_image_external : require\n"
- + "precision mediump float;\n"
- + "varying vec2 interp_tc;\n"
- + "\n"
- + "uniform samplerExternalOES oes_tex;\n"
- + "\n"
- + "void main() {\n"
- + " gl_FragColor = texture2D(oes_tex, interp_tc);\n"
- + "}\n";
- // clang-format on
-
- // Vertex coordinates in Normalized Device Coordinates, i.e. (-1, -1) is bottom-left and (1, 1) is
- // top-right.
- private static final FloatBuffer FULL_RECTANGLE_BUF = GlUtil.createFloatBuffer(new float[] {
- -1.0f, -1.0f, // Bottom left.
- 1.0f, -1.0f, // Bottom right.
- -1.0f, 1.0f, // Top left.
- 1.0f, 1.0f, // Top right.
- });
-
- // Texture coordinates - (0, 0) is bottom-left and (1, 1) is top-right.
- private static final FloatBuffer FULL_RECTANGLE_TEX_BUF = GlUtil.createFloatBuffer(new float[] {
- 0.0f, 0.0f, // Bottom left.
- 1.0f, 0.0f, // Bottom right.
- 0.0f, 1.0f, // Top left.
- 1.0f, 1.0f // Top right.
- });
-
- private static class Shader {
- public final GlShader glShader;
- public final int texMatrixLocation;
-
- public Shader(String fragmentShader) {
- this.glShader = new GlShader(VERTEX_SHADER_STRING, fragmentShader);
- this.texMatrixLocation = glShader.getUniformLocation("texMatrix");
- }
+ @Override
+ public void onPrepareShader(GlShader shader, float[] texMatrix, int frameWidth, int frameHeight,
+ int viewportWidth, int viewportHeight) {}
}
- // The keys are one of the fragments shaders above.
- private final Map<String, Shader> shaders = new IdentityHashMap<String, Shader>();
-
- /**
- * Draw an OES texture frame with specified texture transformation matrix. Required resources are
- * allocated at the first call to this function.
- */
- @Override
- public void drawOes(int oesTextureId, float[] texMatrix, int frameWidth, int frameHeight,
- int viewportX, int viewportY, int viewportWidth, int viewportHeight) {
- prepareShader(OES_FRAGMENT_SHADER_STRING, texMatrix);
- GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
- // updateTexImage() may be called from another thread in another EGL context, so we need to
- // bind/unbind the texture in each draw call so that GLES understads it's a new texture.
- GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, oesTextureId);
- drawRectangle(viewportX, viewportY, viewportWidth, viewportHeight);
- GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, 0);
- }
-
- /**
- * Draw a RGB(A) texture frame with specified texture transformation matrix. Required resources
- * are allocated at the first call to this function.
- */
- @Override
- public void drawRgb(int textureId, float[] texMatrix, int frameWidth, int frameHeight,
- int viewportX, int viewportY, int viewportWidth, int viewportHeight) {
- prepareShader(RGB_FRAGMENT_SHADER_STRING, texMatrix);
- GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
- GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureId);
- drawRectangle(viewportX, viewportY, viewportWidth, viewportHeight);
- // Unbind the texture as a precaution.
- GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, 0);
- }
-
- /**
- * Draw a YUV frame with specified texture transformation matrix. Required resources are
- * allocated at the first call to this function.
- */
- @Override
- public void drawYuv(int[] yuvTextures, float[] texMatrix, int frameWidth, int frameHeight,
- int viewportX, int viewportY, int viewportWidth, int viewportHeight) {
- prepareShader(YUV_FRAGMENT_SHADER_STRING, texMatrix);
- // Bind the textures.
- for (int i = 0; i < 3; ++i) {
- GLES20.glActiveTexture(GLES20.GL_TEXTURE0 + i);
- GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, yuvTextures[i]);
- }
- drawRectangle(viewportX, viewportY, viewportWidth, viewportHeight);
- // Unbind the textures as a precaution..
- for (int i = 0; i < 3; ++i) {
- GLES20.glActiveTexture(GLES20.GL_TEXTURE0 + i);
- GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, 0);
- }
- }
-
- private void drawRectangle(int x, int y, int width, int height) {
- // Draw quad.
- GLES20.glViewport(x, y, width, height);
- GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
- }
-
- private void prepareShader(String fragmentShader, float[] texMatrix) {
- final Shader shader;
- if (shaders.containsKey(fragmentShader)) {
- shader = shaders.get(fragmentShader);
- } else {
- // Lazy allocation.
- shader = new Shader(fragmentShader);
- shaders.put(fragmentShader, shader);
- shader.glShader.useProgram();
- // Initialize fragment shader uniform values.
- if (YUV_FRAGMENT_SHADER_STRING.equals(fragmentShader)) {
- GLES20.glUniform1i(shader.glShader.getUniformLocation("y_tex"), 0);
- GLES20.glUniform1i(shader.glShader.getUniformLocation("u_tex"), 1);
- GLES20.glUniform1i(shader.glShader.getUniformLocation("v_tex"), 2);
- } else if (RGB_FRAGMENT_SHADER_STRING.equals(fragmentShader)) {
- GLES20.glUniform1i(shader.glShader.getUniformLocation("rgb_tex"), 0);
- } else if (OES_FRAGMENT_SHADER_STRING.equals(fragmentShader)) {
- GLES20.glUniform1i(shader.glShader.getUniformLocation("oes_tex"), 0);
- } else {
- throw new IllegalStateException("Unknown fragment shader: " + fragmentShader);
- }
- GlUtil.checkNoGLES2Error("Initialize fragment shader uniform values.");
- // Initialize vertex shader attributes.
- shader.glShader.setVertexAttribArray("in_pos", 2, FULL_RECTANGLE_BUF);
- shader.glShader.setVertexAttribArray("in_tc", 2, FULL_RECTANGLE_TEX_BUF);
- }
- shader.glShader.useProgram();
- // Copy the texture transformation matrix over.
- GLES20.glUniformMatrix4fv(shader.texMatrixLocation, 1, false, texMatrix, 0);
- }
-
- /**
- * Release all GLES resources. This needs to be done manually, otherwise the resources are leaked.
- */
- @Override
- public void release() {
- for (Shader shader : shaders.values()) {
- shader.glShader.release();
- }
- shaders.clear();
+ public GlRectDrawer() {
+ super(FRAGMENT_SHADER, new ShaderCallbacks());
}
}