1 /*
2  * Copyright (C) 2013 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 <stdlib.h>
18 #include <stdio.h>
19 
20 #include <EGL/egl.h>
21 #include <GLES2/gl2.h>
22 
23 #include "util.h"
24 
25 static const char gVertexShader[] =
26 	"attribute vec4 aPosition;\n"
27 	"uniform mat4 uTransform;\n"
28 	"varying vec4 vTexCoord;\n"
29 	"void main() {\n"
30 	"  gl_Position = aPosition * uTransform;\n"
31 	"  vTexCoord = aPosition * vec4(1.0/16.0,-1.0/16.0,0.0,0.0);\n"
32 	"}\n";
33 
34 static const char gFragmentShader[] =
35 	"precision mediump float;\n"
36 	"uniform sampler2D uTexture;\n"
37 	"uniform float uAnim;\n"
38 	"varying vec4 vTexCoord;\n"
39 	"void main() {\n"
40 	"  vec2 tc = vec2(vTexCoord.x, uAnim + vTexCoord.y);\n"
41 	"  gl_FragColor = texture2D(uTexture, tc);\n"
42 	"}\n";
43 
44 static GLuint pgm;
45 static GLint aPosition, uTransform, uTexture, uAnim;
46 
47 static GLfloat vtx[2 * 3 * 2];
48 static GLfloat mtx[16];
49 
50 //#define R (0xFF0000FF)
51 #define R (0xFF000000)
52 #define G (0xFF00FF00)
53 uint32_t t32[] = {
54 	R, R, R, R, R, R, R, G, G, R, R, R, R, R, R, R,
55 	R, R, R, R, R, R, G, G, G, G, R, R, R, R, R, R,
56 	R, R, R, R, R, G, G, G, G, G, G, R, R, R, R, R,
57 	R, R, R, R, G, G, G, G, G, G, G, G, R, R, R, R,
58 	R, R, R, G, G, G, G, G, G, G, G, G, G, R, R, R,
59 	R, R, G, G, G, G, G, G, G, G, G, G, G, G, R, R,
60 	R, R, G, G, G, G, G, G, G, G, G, G, G, G, R, R,
61 	R, R, R, R, R, R, G, G, G, G, R, R, R, R, R, R,
62 	R, R, R, R, R, R, G, G, G, G, R, R, R, R, R, R,
63 	R, R, R, R, R, R, G, G, G, G, R, R, R, R, R, R,
64 	R, R, R, R, R, R, G, G, G, G, R, R, R, R, R, R,
65 	R, R, R, R, R, R, G, G, G, G, R, R, R, R, R, R,
66 	R, R, R, R, R, R, G, G, G, G, R, R, R, R, R, R,
67 	R, R, R, R, R, R, R, R, R, R, R, R, R, R, R, R,
68 	R, R, R, R, R, R, R, R, R, R, R, R, R, R, R, R,
69 	R, R, R, R, R, R, R, R, R, R, R, R, R, R, R, R,
70 };
71 #undef R
72 #undef G
73 
prepare(int w,int h)74 int prepare(int w, int h) {
75 	GLuint texid;
76 
77 	int left = w / 4;
78 	int top = h / 4;
79 	int right = (w / 4) * 3;
80 	int bottom = (h / 4) * 3;
81 
82 	vtx[0] = left;
83 	vtx[1] = top;
84 	vtx[2] = left;
85 	vtx[3] = bottom;
86 	vtx[4] = right;
87 	vtx[5] = bottom;
88 
89 	vtx[6] = right;
90 	vtx[7] = bottom;
91 	vtx[8] = right;
92 	vtx[9] = top;
93 	vtx[10] = left;
94 	vtx[11] = top;
95 
96 	matrix_init_ortho(mtx, w, h);
97 
98 	pgm = load_program(gVertexShader, gFragmentShader);
99 	if (!pgm)
100 		return -1;
101 
102 	aPosition = glGetAttribLocation(pgm, "aPosition");
103 	uTexture = glGetUniformLocation(pgm, "uTexture");
104 	uTransform = glGetUniformLocation(pgm, "uTransform");
105 	uAnim = glGetUniformLocation(pgm, "uAnim");
106 
107 	glViewport(0, 0, w, h);
108 
109 	glGenTextures(1, &texid);
110 	glActiveTexture(GL_TEXTURE0);
111 	glBindTexture(GL_TEXTURE_2D, texid);
112 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
113 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
114 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
115 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
116 	glEnable(GL_TEXTURE_2D);
117 	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 16, 16, 0,
118 		GL_RGBA, GL_UNSIGNED_BYTE, t32);
119 
120 	return 0;
121 }
122 
123 static float anim = 0.0;
124 
render()125 void render() {
126 	anim += 0.1;
127 	if (anim >= 16.0) anim = 0.0;
128 
129 	glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
130 	glClear(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
131 	glUseProgram(pgm);
132 	glUniform1i(uTexture, 0);
133 	glUniform1f(uAnim, anim);
134 	glUniformMatrix4fv(uTransform, 1, 0, mtx);
135 	glVertexAttribPointer(aPosition, 2, GL_FLOAT, GL_FALSE, 0, vtx);
136 	glEnableVertexAttribArray(aPosition);
137 	glDrawArrays(GL_TRIANGLES, 0, 6);
138 }
139 
main(int argc,char ** argv)140 int main(int argc, char **argv) {
141 	EGLDisplay display;
142 	EGLSurface surface;
143 	int w, h, count = 0;
144 
145 	if (argc > 1)
146 		count = atoi(argv[1]);
147 
148 	if (egl_create(&display, &surface, &w, &h))
149 		return -1;
150 
151 	if (prepare(w, h))
152 		return -1;
153 
154 	for (;;) {
155 		render();
156 		eglSwapBuffers(display, surface);
157 		if (count > 0)
158 			if (--count == 0)
159 				break;
160 	}
161 
162 	egl_destroy(display, surface);
163 	return 0;
164 }
165