| // |
| // Copyright (c) 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_VertexShader.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 "shader_utils.h" |
| #include "texture_utils.h" |
| #include "geometry_utils.h" |
| #include "Matrix.h" |
| |
| #include <cmath> |
| |
| class SimpleVertexShaderSample : public SampleApplication |
| { |
| public: |
| SimpleVertexShaderSample() |
| : SampleApplication("SimpleVertexShader", 1280, 720) |
| { |
| } |
| |
| virtual bool initialize() |
| { |
| const std::string vs = SHADER_SOURCE |
| ( |
| uniform mat4 u_mvpMatrix; |
| attribute vec4 a_position; |
| attribute vec2 a_texcoord; |
| varying vec2 v_texcoord; |
| void main() |
| { |
| gl_Position = u_mvpMatrix * a_position; |
| v_texcoord = a_texcoord; |
| } |
| ); |
| |
| const std::string fs = SHADER_SOURCE |
| ( |
| precision mediump float; |
| varying vec2 v_texcoord; |
| void main() |
| { |
| gl_FragColor = vec4(v_texcoord.x, v_texcoord.y, 1.0, 1.0); |
| } |
| ); |
| |
| mProgram = CompileProgram(vs, fs); |
| if (!mProgram) |
| { |
| return false; |
| } |
| |
| // Get the attribute locations |
| mPositionLoc = glGetAttribLocation(mProgram, "a_position"); |
| mTexcoordLoc = glGetAttribLocation(mProgram, "a_texcoord"); |
| |
| // Get the uniform locations |
| mMVPMatrixLoc = glGetUniformLocation(mProgram, "u_mvpMatrix"); |
| |
| // Generate the geometry data |
| GenerateCubeGeometry(0.5f, &mCube); |
| |
| // Set an initial rotation |
| mRotation = 45.0f; |
| |
| glClearColor(0.0f, 0.0f, 0.0f, 0.0f); |
| glCullFace(GL_BACK); |
| glEnable(GL_CULL_FACE); |
| |
| return true; |
| } |
| |
| virtual void destroy() |
| { |
| glDeleteProgram(mProgram); |
| } |
| |
| virtual void step(float dt, double totalTime) |
| { |
| mRotation = fmod(mRotation + (dt * 40.0f), 360.0f); |
| |
| Matrix4 perspectiveMatrix = Matrix4::perspective(60.0f, float(getWindow()->getWidth()) / getWindow()->getHeight(), |
| 1.0f, 20.0f); |
| |
| Matrix4 modelMatrix = Matrix4::translate(angle::Vector3(0.0f, 0.0f, -2.0f)) * |
| Matrix4::rotate(mRotation, angle::Vector3(1.0f, 0.0f, 1.0f)); |
| |
| Matrix4 viewMatrix = Matrix4::identity(); |
| |
| Matrix4 mvpMatrix = perspectiveMatrix * viewMatrix * modelMatrix; |
| |
| // Load the matrices |
| glUniformMatrix4fv(mMVPMatrixLoc, 1, GL_FALSE, mvpMatrix.data); |
| } |
| |
| virtual void draw() |
| { |
| // 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, mCube.positions.data()); |
| glEnableVertexAttribArray(mPositionLoc); |
| |
| // Load the texcoord data |
| glVertexAttribPointer(mTexcoordLoc, 2, GL_FLOAT, GL_FALSE, 0, mCube.texcoords.data()); |
| glEnableVertexAttribArray(mTexcoordLoc); |
| |
| // Draw the cube |
| glDrawElements(GL_TRIANGLES, static_cast<GLsizei>(mCube.indices.size()), GL_UNSIGNED_SHORT, |
| mCube.indices.data()); |
| } |
| |
| private: |
| // Handle to a program object |
| GLuint mProgram; |
| |
| // Attribute locations |
| GLint mPositionLoc; |
| GLint mTexcoordLoc; |
| |
| // Uniform locations |
| GLuint mMVPMatrixLoc; |
| |
| // Current rotation |
| float mRotation; |
| |
| // Geometry data |
| CubeGeometry mCube; |
| }; |
| |
| int main(int argc, char **argv) |
| { |
| SimpleVertexShaderSample app; |
| return app.run(); |
| } |