1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.mediafx;
import android.opengl.GLES20;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
public class TextureRenderer {
private int mProgram;
private int mTexSamplerHandle;
private int mTexCoordHandle;
private int mPosCoordHandle;
private FloatBuffer mTexVertices;
private FloatBuffer mPosVertices;
private int mViewWidth;
private int mViewHeight;
private int mTexWidth;
private int mTexHeight;
private static final String VERTEX_SHADER =
"attribute vec4 a_position;\n" +
"attribute vec2 a_texcoord;\n" +
"varying vec2 v_texcoord;\n" +
"void main() {\n" +
" gl_Position = a_position;\n" +
" v_texcoord = a_texcoord;\n" +
"}\n";
private static final String FRAGMENT_SHADER =
"precision mediump float;\n" +
"uniform sampler2D tex_sampler;\n" +
"varying vec2 v_texcoord;\n" +
"void main() {\n" +
" gl_FragColor = texture2D(tex_sampler, v_texcoord);\n" +
"}\n";
private static final float[] TEX_VERTICES = {
0.0f, 1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f
};
private static final float[] POS_VERTICES = {
-1.0f, -1.0f, 1.0f, -1.0f, -1.0f, 1.0f, 1.0f, 1.0f
};
private static final int FLOAT_SIZE_BYTES = 4;
public void init() {
// Create program
mProgram = GLToolbox.createProgram(VERTEX_SHADER, FRAGMENT_SHADER);
// Bind attributes and uniforms
mTexSamplerHandle = GLES20.glGetUniformLocation(mProgram,
"tex_sampler");
mTexCoordHandle = GLES20.glGetAttribLocation(mProgram, "a_texcoord");
mPosCoordHandle = GLES20.glGetAttribLocation(mProgram, "a_position");
// Setup coordinate buffers
mTexVertices = ByteBuffer.allocateDirect(
TEX_VERTICES.length * FLOAT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
mTexVertices.put(TEX_VERTICES).position(0);
mPosVertices = ByteBuffer.allocateDirect(
POS_VERTICES.length * FLOAT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
mPosVertices.put(POS_VERTICES).position(0);
}
public void tearDown() {
GLES20.glDeleteProgram(mProgram);
}
public void updateTextureSize(int texWidth, int texHeight) {
mTexWidth = texWidth;
mTexHeight = texHeight;
computeOutputVertices();
}
public void updateViewSize(int viewWidth, int viewHeight) {
mViewWidth = viewWidth;
mViewHeight = viewHeight;
computeOutputVertices();
}
public void renderTexture(int texId) {
// Bind default FBO
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);
// Use our shader program
GLES20.glUseProgram(mProgram);
GLToolbox.checkGlError("glUseProgram");
// Set viewport
GLES20.glViewport(0, 0, mViewWidth, mViewHeight);
GLToolbox.checkGlError("glViewport");
// Disable blending
GLES20.glDisable(GLES20.GL_BLEND);
// Set the vertex attributes
GLES20.glVertexAttribPointer(mTexCoordHandle, 2, GLES20.GL_FLOAT, false,
0, mTexVertices);
GLES20.glEnableVertexAttribArray(mTexCoordHandle);
GLES20.glVertexAttribPointer(mPosCoordHandle, 2, GLES20.GL_FLOAT, false,
0, mPosVertices);
GLES20.glEnableVertexAttribArray(mPosCoordHandle);
GLToolbox.checkGlError("vertex attribute setup");
// Set the input texture
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLToolbox.checkGlError("glActiveTexture");
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texId);
GLToolbox.checkGlError("glBindTexture");
GLES20.glUniform1i(mTexSamplerHandle, 0);
// Draw
GLES20.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
}
private void computeOutputVertices() {
if (mPosVertices != null) {
float imgAspectRatio = mTexWidth / (float)mTexHeight;
float viewAspectRatio = mViewWidth / (float)mViewHeight;
float relativeAspectRatio = viewAspectRatio / imgAspectRatio;
float x0, y0, x1, y1;
if (relativeAspectRatio > 1.0f) {
x0 = -1.0f / relativeAspectRatio;
y0 = -1.0f;
x1 = 1.0f / relativeAspectRatio;
y1 = 1.0f;
} else {
x0 = -1.0f;
y0 = -relativeAspectRatio;
x1 = 1.0f;
y1 = relativeAspectRatio;
}
float[] coords = new float[] { x0, y0, x1, y0, x0, y1, x1, y1 };
mPosVertices.put(coords).position(0);
}
}
}
|
