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//
// Copyright 2014 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//
// Based on Simple_TextureCubemap.c from
// Book: OpenGL(R) ES 2.0 Programming Guide
// Authors: Aaftab Munshi, Dan Ginsburg, Dave Shreiner
// ISBN-10: 0321502795
// ISBN-13: 9780321502797
// Publisher: Addison-Wesley Professional
// URLs: http://safari.informit.com/9780321563835
// http://www.opengles-book.com
#include "SampleApplication.h"
#include "texture_utils.h"
#include "util/geometry_utils.h"
#include "util/shader_utils.h"
class SimpleTextureCubemapSample : public SampleApplication
{
public:
SimpleTextureCubemapSample(int argc, char **argv)
: SampleApplication("SimpleTextureCubemap", argc, argv)
{}
bool initialize() override
{
constexpr char kVS[] = R"(attribute vec4 a_position;
attribute vec3 a_normal;
varying vec3 v_normal;
void main()
{
gl_Position = a_position;
v_normal = a_normal;
})";
constexpr char kFS[] = R"(precision mediump float;
varying vec3 v_normal;
uniform samplerCube s_texture;
void main()
{
gl_FragColor = textureCube(s_texture, v_normal);
})";
mProgram = CompileProgram(kVS, kFS);
if (!mProgram)
{
return false;
}
// Get the attribute locations
mPositionLoc = glGetAttribLocation(mProgram, "a_position");
mNormalLoc = glGetAttribLocation(mProgram, "a_normal");
// Get the sampler locations
mSamplerLoc = glGetUniformLocation(mProgram, "s_texture");
// Load the texture
mTexture = CreateSimpleTextureCubemap();
// Generate the geometry data
CreateSphereGeometry(128, 0.75f, &mSphere);
glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
glCullFace(GL_BACK);
glEnable(GL_CULL_FACE);
return true;
}
void destroy() override
{
glDeleteProgram(mProgram);
glDeleteTextures(1, &mTexture);
}
void draw() override
{
// Set the viewport
glViewport(0, 0, getWindow()->getWidth(), getWindow()->getHeight());
// Clear the color buffer
glClear(GL_COLOR_BUFFER_BIT);
// Use the program object
glUseProgram(mProgram);
// Load the vertex position
glVertexAttribPointer(mPositionLoc, 3, GL_FLOAT, GL_FALSE, 0, mSphere.positions.data());
glEnableVertexAttribArray(mPositionLoc);
// Load the normal
glVertexAttribPointer(mNormalLoc, 3, GL_FLOAT, GL_FALSE, 0, mSphere.normals.data());
glEnableVertexAttribArray(mNormalLoc);
// Bind the texture
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_CUBE_MAP, mTexture);
// Set the texture sampler to texture unit to 0
glUniform1i(mSamplerLoc, 0);
glDrawElements(GL_TRIANGLES, static_cast<GLsizei>(mSphere.indices.size()),
GL_UNSIGNED_SHORT, mSphere.indices.data());
}
private:
// Handle to a program object
GLuint mProgram;
// Attribute locations
GLint mPositionLoc;
GLint mNormalLoc;
// Sampler location
GLint mSamplerLoc;
// Texture handle
GLuint mTexture;
// Geometry data
SphereGeometry mSphere;
};
int main(int argc, char **argv)
{
SimpleTextureCubemapSample app(argc, argv);
return app.run();
}
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