1 /*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "RenderDirectView.h"
18 #include "VideoTex.h"
19 #include "glError.h"
20 #include "shader.h"
21 #include "shader_simpleTex.h"
22
23 #include <log/log.h>
24 #include <math/mat4.h>
25
26
RenderDirectView(sp<IEvsEnumerator> enumerator,const ConfigManager::CameraInfo & cam)27 RenderDirectView::RenderDirectView(sp<IEvsEnumerator> enumerator,
28 const ConfigManager::CameraInfo& cam) {
29 mEnumerator = enumerator;
30 mCameraInfo = cam;
31 }
32
33
activate()34 bool RenderDirectView::activate() {
35 // Ensure GL is ready to go...
36 if (!prepareGL()) {
37 ALOGE("Error initializing GL");
38 return false;
39 }
40
41 // Load our shader program if we don't have it already
42 if (!mShaderProgram) {
43 mShaderProgram = buildShaderProgram(vtxShader_simpleTexture,
44 pixShader_simpleTexture,
45 "simpleTexture");
46 if (!mShaderProgram) {
47 ALOGE("Error buliding shader program");
48 return false;
49 }
50 }
51
52 // Construct our video texture
53 mTexture.reset(createVideoTexture(mEnumerator, mCameraInfo.cameraId.c_str(), sDisplay));
54 if (!mTexture) {
55 ALOGE("Failed to set up video texture for %s (%s)",
56 mCameraInfo.cameraId.c_str(), mCameraInfo.function.c_str());
57 // TODO: For production use, we may actually want to fail in this case, but not yet...
58 // return false;
59 }
60
61 return true;
62 }
63
64
deactivate()65 void RenderDirectView::deactivate() {
66 // Release our video texture
67 // We can't hold onto it because some other Render object might need the same camera
68 // TODO: If start/stop costs become a problem, we could share video textures
69 mTexture = nullptr;
70 }
71
72
drawFrame(const BufferDesc & tgtBuffer)73 bool RenderDirectView::drawFrame(const BufferDesc& tgtBuffer) {
74 // Tell GL to render to the given buffer
75 if (!attachRenderTarget(tgtBuffer)) {
76 ALOGE("Failed to attached render target");
77 return false;
78 }
79
80 // Select our screen space simple texture shader
81 glUseProgram(mShaderProgram);
82
83 // Set up the model to clip space transform (identity matrix if we're modeling in screen space)
84 GLint loc = glGetUniformLocation(mShaderProgram, "cameraMat");
85 if (loc < 0) {
86 ALOGE("Couldn't set shader parameter 'cameraMat'");
87 return false;
88 } else {
89 const android::mat4 identityMatrix;
90 glUniformMatrix4fv(loc, 1, false, identityMatrix.asArray());
91 }
92
93
94 // Bind the texture and assign it to the shader's sampler
95 mTexture->refresh();
96 glActiveTexture(GL_TEXTURE0);
97 glBindTexture(GL_TEXTURE_2D, mTexture->glId());
98
99
100 GLint sampler = glGetUniformLocation(mShaderProgram, "tex");
101 if (sampler < 0) {
102 ALOGE("Couldn't set shader parameter 'tex'");
103 return false;
104 } else {
105 // Tell the sampler we looked up from the shader to use texture slot 0 as its source
106 glUniform1i(sampler, 0);
107 }
108
109 // We want our image to show up opaque regardless of alpha values
110 glDisable(GL_BLEND);
111
112
113 // Draw a rectangle on the screen
114 GLfloat vertsCarPos[] = { -1.0, 1.0, 0.0f, // left top in window space
115 1.0, 1.0, 0.0f, // right top
116 -1.0, -1.0, 0.0f, // left bottom
117 1.0, -1.0, 0.0f // right bottom
118 };
119 // TODO: We're flipping horizontally here, but should do it only for specified cameras!
120 GLfloat vertsCarTex[] = { 1.0f, 1.0f, // left top
121 0.0f, 1.0f, // right top
122 1.0f, 0.0f, // left bottom
123 0.0f, 0.0f // right bottom
124 };
125 glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, vertsCarPos);
126 glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 0, vertsCarTex);
127 glEnableVertexAttribArray(0);
128 glEnableVertexAttribArray(1);
129
130 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
131
132 glDisableVertexAttribArray(0);
133 glDisableVertexAttribArray(1);
134
135
136 // Wait for the rendering to finish
137 glFinish();
138
139 return true;
140 }
141