Files
eepp/src/examples/external_shader/external_shader.cpp
Martín Lucas Golini ba3781229d Graphic module improvements.
--HG--
branch : dev
2017-02-17 23:22:49 -03:00

288 lines
8.2 KiB
C++

#include <eepp/ee.hpp>
#include <eepp/graphics/opengl.hpp>
/// This example is based on the WebGL demo from http://minimal.be/lab/fluGL/
namespace Demo_ExternalShader {
#if defined( EE_ARM ) || EE_PLATFORM == EE_PLATFORM_EMSCRIPTEN
static Float sqrt_aprox[20001];
#endif
Uint32 ParticlesNum = 30000;
EE::Window::Window * win = NULL;
Input * imp = NULL;
ShaderProgram * shaderProgram = NULL;
bool ShadersSupported = false;
Float tw;
Float th;
Float aspectRatio;
Vector3ff * vertices = eeNewArray( Vector3ff, ParticlesNum );
Vector3ff * velocities = eeNewArray( Vector3ff, ParticlesNum );
ColorAf * colors = eeNewArray( ColorAf, ParticlesNum );
void videoResize( EE::Window::Window * w ) {
/// Video Resize event will re-setup the 2D projection and states, so we must rebuild them.
aspectRatio = (Float)win->getWidth() / (Float)win->getHeight();
tw = (Float)win->getWidth() / 2;
th = (Float)win->getHeight() / 2;
float fieldOfView = 30.0;
float nearPlane = 1.0;
float farPlane = 10000.0;
float top = nearPlane * eetan(fieldOfView * EE_PI_360);
float bottom = -top;
float right = top * aspectRatio;
float left = -right;
float a = (right + left) / (right - left);
float b = (top + bottom) / (top - bottom);
float c = (farPlane + nearPlane) / (farPlane - nearPlane);
float d = (2 * farPlane * nearPlane) / (farPlane - nearPlane);
float x = (2 * nearPlane) / (right - left);
float y = (2 * nearPlane) / (top - bottom);
float perspectiveMatrix[16] = {
x, 0, a, 0,
0, y, b, 0,
0, 0, c, d,
0, 0, -1, 0
};
/// Load the our default projection
GLi->matrixMode( GL_PROJECTION );
GLi->loadMatrixf( perspectiveMatrix );
GLi->matrixMode( GL_MODELVIEW );
/// eepp enables some client states by default, and textures by default
GLi->disable( GL_TEXTURE_2D );
GLi->disableClientState( GL_TEXTURE_COORD_ARRAY );
/// GL_VERTEX_ARRAY and GL_COLOR_ARRAY are needed, so we keep them enabled
GLi->enableClientState( GL_VERTEX_ARRAY );
GLi->enableClientState( GL_COLOR_ARRAY );
/// Reset the default blend func ( by default eepp use ALPHA_NORMAL )
BlendMode::setMode( ALPHA_BLENDONE );
/// Set the line width
GlobalBatchRenderer::instance()->setLineWidth( 2 );
if ( ShadersSupported ) {
/// Rebind the Shader
shaderProgram->bind();
/// If you want to use the programmable-pipeline renderer you'll need to set up the projection and modelview matrix manually.
/// Or if you want to use another name to the projection matrix or the modelview matrix ( eepp programmable-pipeline use
/// dgl_ProjectionMatrix and dgl_ModelViewMatrix by default.
if ( GLv_2 == GLi->version() ) {
shaderProgram->setUniformMatrix( "dgl_ProjectionMatrix", perspectiveMatrix );
/// Get the identity matrix and set it to the modelview matrix
float modelMatrix[16];
GLi->loadIdentity();
GLi->getCurrentMatrix( GL_MODELVIEW_MATRIX, modelMatrix );
shaderProgram->setUniformMatrix( "dgl_ModelViewMatrix", modelMatrix );
}
}
}
}
using namespace Demo_ExternalShader;
void MainLoop()
{
win->clear();
imp->update();
if ( imp->isKeyDown( KEY_ESCAPE ) )
{
win->close();
}
if ( imp->isKeyUp( KEY_F ) )
{
if ( win->isWindowed() ) {
win->setSize( win->getDesktopResolution().getWidth(), win->getDesktopResolution().getHeight(), false );
} else {
win->setSize( 960, 640, true );
win->centerToScreen();
}
}
Float p;
Vector2f mf = imp->getMousePosf();
Float tratio = tw / th;
Float touchX = ( mf.x / tw - 1 ) * tratio;
Float touchY = -( mf.y / th - 1 );
bool touch = imp->isMouseLeftPressed();
for( Uint32 i = 0; i < ParticlesNum; i+=2 )
{
// copy old positions
vertices[i].x = vertices[i+1].x;
vertices[i].y = vertices[i+1].y;
// inertia
velocities[i].x *= velocities[i].z;
velocities[i].y *= velocities[i].z;
// horizontal
p = vertices[i+1].x;
p += velocities[i].x;
if ( p < -aspectRatio ) {
p = -aspectRatio;
velocities[i].x = eeabs(velocities[i].x);
} else if ( p > aspectRatio ) {
p = aspectRatio;
velocities[i].x = -eeabs(velocities[i].x);
}
vertices[i+1].x = p;
// vertical
p = vertices[i+1].y;
p += velocities[i].y;
if ( p < -aspectRatio ) {
p = -aspectRatio;
velocities[i].y = eeabs(velocities[i].y);
} else if ( p > aspectRatio ) {
p = aspectRatio;
velocities[i].y = -eeabs(velocities[i].y);
}
vertices[i+1].y = p;
if ( touch ) {
Float dx = touchX - vertices[i].x;
Float dy = touchY - vertices[i].y;
Float distance = dx * dx + dy * dy;
#if !defined( EE_ARM ) && EE_PLATFORM != EE_PLATFORM_EMSCRIPTEN
Float d = eesqrt( distance );
#else
Float d = sqrt_aprox[ (Int32)(distance * 1000) ];
#endif
if ( d < 2.f ) {
if ( d < 0.03f ) {
vertices[i+1].x = Math::randf( -1, 1 ) * aspectRatio;
vertices[i+1].y = Math::randf( -1, 1 );
velocities[i].x = 0;
velocities[i].y = 0;
} else {
dx /= d;
dy /= d;
d = ( 2 - d ) * 0.5;
d *= d;
velocities[i].x += dx * d * .01;
velocities[i].y += dy * d * .01;
}
}
}
}
/// VertexPointer assigns values by default to the attribute "dgl_Vertex"
/// TextureCoordPointer to "dgl_MultiTexCoord0"
GLi->vertexPointer( 3, GL_FLOAT, sizeof(Vector3ff), reinterpret_cast<char*> ( &vertices[0] ), ParticlesNum * sizeof(float) * 3 );
/// ColorPointer to "dgl_FrontColor"
GLi->colorPointer( 4, GL_FP, sizeof(ColorAf), reinterpret_cast<char*> ( &colors[0] ), ParticlesNum * sizeof(Float) * 4 );
/// Draw the lines
GLi->drawArrays( DM_LINES, 0, ParticlesNum );
/// Stop the simulation if the window is not visible
while ( !win->isVisible() ) {
imp->update(); /// To get the real state of the window you need to update the window input
Sys::sleep( 100 ); /// Sleep 100 ms
}
win->display();
}
EE_MAIN_FUNC int main (int argc, char * argv [])
{
win = Engine::instance()->createWindow( WindowSettings( 960, 640, "eepp - External Shaders" ), ContextSettings( true ) );
if ( win->isOpen() )
{
/// This will work without shaders too
ShadersSupported = GLi->shadersSupported();
imp = win->getInput();
/// We really don't need shaders for this, but the purpose of the example is to show how to work with external shaders
if ( ShadersSupported ) {
/// Disable the automatic shader conversion from fixed-pipeline to programmable-pipeline
Shader::ensure( false );
std::string fs( "#ifdef GL_ES\n\
precision highp float;\n\
#endif\n\
varying vec4 dgl_Color;\n\
void main() { gl_FragColor = dgl_Color; }" );
std::string vs( "#ifdef GL_ES\n\
precision highp float;\n\
#endif\n\
attribute vec3 dgl_Vertex;\n\
attribute vec4 dgl_FrontColor;\n\
varying vec4 dgl_Color;\n\
uniform mat4 dgl_ProjectionMatrix;\n\
uniform mat4 dgl_ModelViewMatrix;\n\
void main() {\n\
dgl_Color = dgl_FrontColor;\n\
gl_Position = dgl_ProjectionMatrix * dgl_ModelViewMatrix * vec4(dgl_Vertex, 1.0);\n\
}");
/// Since fixed-pipeline OpenGL use gl_FrontColor for glColorPointer, we need to replace the color attribute
/// This is all to show how it works, in a real world scenario, you will choose to work fixed-pipeline or programmable-pipeline.
if ( GLi->version() == GLv_2 ) {
String::replaceAll( fs, "gl_FragColor = dgl_Color", "gl_FragColor = gl_FrontColor" );
}
/// Create the new shader program
shaderProgram = ShaderProgram::New( vs.c_str(), vs.size(), fs.c_str(), fs.size() );
}
/// Set the projection
videoResize( win );
/// Push a window resize callback the reset the projection when needed
win->pushResizeCallback( cb::Make1( &videoResize ) );
Uint32 i;
for (i = 0; i < ParticlesNum; i++ )
{
vertices[i] = Vector3ff( 0, 0, 1.83 );
velocities[i] = Vector3ff( (Math::randf() * 2 - 1)*.05, (Math::randf() * 2 - 1)*.05, .93 + Math::randf()*.02 );
colors[i] = ColorAf( Math::randf() * 0.5, 0.1, 0.8, 0.5 );
}
/** Optimized for ARM ( pre-cache sqrt ) */
#if defined( EE_ARM ) || EE_PLATFORM == EE_PLATFORM_EMSCRIPTEN
Float tFloat = 0;
for ( int i = 0; i <= 20000; i++ ) {
sqrt_aprox[i] = eesqrt( tFloat );
tFloat += 0.001;
}
#endif
win->runMainLoop( &MainLoop );
eeSAFE_DELETE_ARRAY( vertices );
eeSAFE_DELETE_ARRAY( velocities );
eeSAFE_DELETE_ARRAY( colors );
}
Engine::destroySingleton();
MemoryManager::showResults();
return EXIT_SUCCESS;
}