1 files changed, 319 insertions, 0 deletions
diff --git a/apps/openmb/renderer/SSAORenderer.cpp b/apps/openmb/renderer/SSAORenderer.cpp
new file mode 100644
index 0000000..8493529
--- /dev/null
+++ b/apps/openmb/renderer/SSAORenderer.cpp
@@ -0,0 +1,319 @@
+#include "SSAORenderer.hpp"
+
+#define GLFW_INCLUDE_NONE
+#include <GLFW/glfw3.h>
+#ifdef __APPLE__
+#include <OpenGL/gl3.h>
+#endif
+#include <glm/gtc/type_ptr.hpp>
+#include <iostream>
+#include <random>
+
+namespace renderer {
+
+SSAORenderer::SSAORenderer ()
+    : mWidth( 0 ), mHeight( 0 ), mHalfRes( true ), mKernelSize( 32 ), mGBufferFBO( 0 ), mGNormal( 0 ), mGDepth( 0 ),
+      mSSAOFBO( 0 ), mSSAOTexture( 0 ), mSSAOBlurFBO( 0 ), mSSAOBlurTexture( 0 ), mNoiseTexture( 0 ), mQuadVAO( 0 ),
+      mQuadVBO( 0 ) {
+}
+
+SSAORenderer::~SSAORenderer () {
+    if( mGNormal )
+        glDeleteTextures( 1, &mGNormal );
+    if( mGDepth )
+        glDeleteTextures( 1, &mGDepth );
+    if( mGBufferFBO )
+        glDeleteFramebuffers( 1, &mGBufferFBO );
+    if( mSSAOTexture )
+        glDeleteTextures( 1, &mSSAOTexture );
+    if( mSSAOBlurTexture )
+        glDeleteTextures( 1, &mSSAOBlurTexture );
+    if( mSSAOFBO )
+        glDeleteFramebuffers( 1, &mSSAOFBO );
+    if( mSSAOBlurFBO )
+        glDeleteFramebuffers( 1, &mSSAOBlurFBO );
+    if( mNoiseTexture )
+        glDeleteTextures( 1, &mNoiseTexture );
+    if( mQuadVBO )
+        glDeleteBuffers( 1, &mQuadVBO );
+    if( mQuadVAO )
+        glDeleteVertexArrays( 1, &mQuadVAO );
+}
+
+bool SSAORenderer::init ( int width, int height, bool halfRes ) {
+    mWidth   = width;
+    mHeight  = height;
+    mHalfRes = halfRes;
+
+    if( !mGBufferShader.fromFiles( "apps/openmb/resources/shaders/gbuffer.vert",
+                                   "apps/openmb/resources/shaders/gbuffer.frag" ) ) {
+        std::cerr << "Failed to load gbuffer shader" << std::endl;
+        return false;
+    }
+    if( !mSSAOShader.fromFiles( "apps/openmb/resources/shaders/ssao.vert",
+                                "apps/openmb/resources/shaders/ssao.frag" ) ) {
+        std::cerr << "Failed to load ssao shader" << std::endl;
+        return false;
+    }
+    if( !mBlurShader.fromFiles( "apps/openmb/resources/shaders/ssao.vert",
+                                "apps/openmb/resources/shaders/ssao_blur.frag" ) ) {
+        std::cerr << "Failed to load ssao blur shader" << std::endl;
+        return false;
+    }
+
+    initBuffers();
+    initKernelAndNoise();
+
+    float quadVertices[] = {
+
+        -1.0f,
+        -1.0f,
+        0.0f,
+        0.0f,
+        1.0f,
+        -1.0f,
+        1.0f,
+        0.0f,
+        -1.0f,
+        1.0f,
+        0.0f,
+        1.0f,
+        -1.0f,
+        1.0f,
+        0.0f,
+        1.0f,
+        1.0f,
+        -1.0f,
+        1.0f,
+        0.0f,
+        1.0f,
+        1.0f,
+        1.0f,
+        1.0f,
+    };
+
+    glGenVertexArrays( 1, &mQuadVAO );
+    glGenBuffers( 1, &mQuadVBO );
+    glBindVertexArray( mQuadVAO );
+    glBindBuffer( GL_ARRAY_BUFFER, mQuadVBO );
+    glBufferData( GL_ARRAY_BUFFER, sizeof( quadVertices ), quadVertices, GL_STATIC_DRAW );
+    glEnableVertexAttribArray( 0 );
+    glVertexAttribPointer( 0, 2, GL_FLOAT, GL_FALSE, 4 * sizeof( float ), (void*)0 );
+    glEnableVertexAttribArray( 1 );
+    glVertexAttribPointer( 1, 2, GL_FLOAT, GL_FALSE, 4 * sizeof( float ), (void*)( 2 * sizeof( float ) ) );
+    glBindVertexArray( 0 );
+
+    return true;
+}
+
+void SSAORenderer::initBuffers () {
+
+    if( mGBufferFBO == 0 )
+        glGenFramebuffers( 1, &mGBufferFBO );
+    glBindFramebuffer( GL_FRAMEBUFFER, mGBufferFBO );
+
+    if( mGNormal )
+        glDeleteTextures( 1, &mGNormal );
+    glGenTextures( 1, &mGNormal );
+    glBindTexture( GL_TEXTURE_2D, mGNormal );
+    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB16F, mWidth, mHeight, 0, GL_RGB, GL_FLOAT, nullptr );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
+    glFramebufferTexture2D( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, mGNormal, 0 );
+
+    if( mGDepth )
+        glDeleteTextures( 1, &mGDepth );
+    glGenTextures( 1, &mGDepth );
+    glBindTexture( GL_TEXTURE_2D, mGDepth );
+    glTexImage2D( GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, mWidth, mHeight, 0, GL_DEPTH_COMPONENT, GL_FLOAT, nullptr );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE, GL_NONE );
+    glFramebufferTexture2D( GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, mGDepth, 0 );
+
+    GLenum attachments[1] = { GL_COLOR_ATTACHMENT0 };
+    glDrawBuffers( 1, attachments );
+
+    if( glCheckFramebufferStatus( GL_FRAMEBUFFER ) != GL_FRAMEBUFFER_COMPLETE )
+        std::cerr << "GBuffer not complete" << std::endl;
+    glBindFramebuffer( GL_FRAMEBUFFER, 0 );
+
+    if( mSSAOFBO == 0 )
+        glGenFramebuffers( 1, &mSSAOFBO );
+    glBindFramebuffer( GL_FRAMEBUFFER, mSSAOFBO );
+    if( mSSAOTexture )
+        glDeleteTextures( 1, &mSSAOTexture );
+    glGenTextures( 1, &mSSAOTexture );
+    glBindTexture( GL_TEXTURE_2D, mSSAOTexture );
+    int w = mHalfRes ? std::max( 1, mWidth / 2 ) : mWidth;
+    int h = mHalfRes ? std::max( 1, mHeight / 2 ) : mHeight;
+    glTexImage2D( GL_TEXTURE_2D, 0, GL_R8, w, h, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
+    glFramebufferTexture2D( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, mSSAOTexture, 0 );
+    if( glCheckFramebufferStatus( GL_FRAMEBUFFER ) != GL_FRAMEBUFFER_COMPLETE )
+        std::cerr << "SSAO FBO not complete" << std::endl;
+    glBindFramebuffer( GL_FRAMEBUFFER, 0 );
+
+    if( mSSAOBlurFBO == 0 )
+        glGenFramebuffers( 1, &mSSAOBlurFBO );
+    glBindFramebuffer( GL_FRAMEBUFFER, mSSAOBlurFBO );
+    if( mSSAOBlurTexture )
+        glDeleteTextures( 1, &mSSAOBlurTexture );
+    glGenTextures( 1, &mSSAOBlurTexture );
+    glBindTexture( GL_TEXTURE_2D, mSSAOBlurTexture );
+    glTexImage2D( GL_TEXTURE_2D, 0, GL_R8, w, h, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
+    glFramebufferTexture2D( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, mSSAOBlurTexture, 0 );
+    if( glCheckFramebufferStatus( GL_FRAMEBUFFER ) != GL_FRAMEBUFFER_COMPLETE )
+        std::cerr << "SSAO Blur FBO not complete" << std::endl;
+    glBindFramebuffer( GL_FRAMEBUFFER, 0 );
+}
+
+void SSAORenderer::initKernelAndNoise () {
+    mKernel.clear();
+    std::uniform_real_distribution<float> randomFloats( 0.0f, 1.0f );
+    std::mt19937                          gen;
+
+    for( int i = 0; i < mKernelSize; ++i ) {
+        glm::vec3 sample( randomFloats( gen ) * 2.0f - 1.0f, randomFloats( gen ) * 2.0f - 1.0f,
+                          randomFloats( gen ) );
+        sample = glm::normalize( sample );
+        sample *= randomFloats( gen );
+        float scale = float( i ) / float( mKernelSize );
+        scale       = glm::mix( 0.1f, 1.0f, scale * scale );
+        sample *= scale;
+        mKernel.push_back( sample );
+    }
+
+    mSSAOShader.use();
+    for( int i = 0; i < mKernelSize; ++i ) {
+        mSSAOShader.setVec3( std::string( "samples[" ) + std::to_string( i ) + std::string( "]" ), mKernel[i] );
+    }
+    mSSAOShader.setInt( "kernelSize", mKernelSize );
+
+    std::vector<float> noise;
+    for( int i = 0; i < 16; ++i ) {
+        float x = randomFloats( gen ) * 2.0f - 1.0f;
+        float y = randomFloats( gen ) * 2.0f - 1.0f;
+        noise.push_back( x );
+        noise.push_back( y );
+        noise.push_back( 0.0f );
+    }
+    if( mNoiseTexture )
+        glDeleteTextures( 1, &mNoiseTexture );
+    glGenTextures( 1, &mNoiseTexture );
+    glBindTexture( GL_TEXTURE_2D, mNoiseTexture );
+    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB32F, 4, 4, 0, GL_RGB, GL_FLOAT, noise.data() );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT );
+    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT );
+    glBindTexture( GL_TEXTURE_2D, 0 );
+}
+
+void SSAORenderer::resize ( int width, int height ) {
+    if( width == mWidth && height == mHeight )
+        return;
+    mWidth  = width;
+    mHeight = height;
+    initBuffers();
+}
+
+void SSAORenderer::bindGBuffer () {
+    glBindFramebuffer( GL_FRAMEBUFFER, mGBufferFBO );
+    glViewport( 0, 0, mWidth, mHeight );
+    glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
+}
+
+void SSAORenderer::unbind () {
+    glBindFramebuffer( GL_FRAMEBUFFER, 0 );
+}
+
+void SSAORenderer::computeSSAO ( const glm::mat4& proj, const glm::mat4& invProj, float radius, float bias,
+                                 float power ) {
+    int w = mHalfRes ? std::max( 1, mWidth / 2 ) : mWidth;
+    int h = mHalfRes ? std::max( 1, mHeight / 2 ) : mHeight;
+
+    glBindFramebuffer( GL_FRAMEBUFFER, mSSAOFBO );
+    glViewport( 0, 0, w, h );
+    glClear( GL_COLOR_BUFFER_BIT );
+
+    mSSAOShader.use();
+    mSSAOShader.setMat4( "proj", proj );
+    mSSAOShader.setMat4( "invProj", invProj );
+    mSSAOShader.setFloat( "radius", radius );
+    mSSAOShader.setFloat( "bias", bias );
+    mSSAOShader.setFloat( "power", power );
+
+    glActiveTexture( GL_TEXTURE0 );
+    glBindTexture( GL_TEXTURE_2D, mGDepth );
+    mSSAOShader.setInt( "gDepth", 0 );
+
+    glActiveTexture( GL_TEXTURE1 );
+    glBindTexture( GL_TEXTURE_2D, mGNormal );
+    mSSAOShader.setInt( "gNormal", 1 );
+
+    glActiveTexture( GL_TEXTURE2 );
+    glBindTexture( GL_TEXTURE_2D, mNoiseTexture );
+    mSSAOShader.setInt( "texNoise", 2 );
+
+    float noiseScaleVal = float( w ) / 4.0f;
+    mSSAOShader.setInt( "gDepth", 0 );
+    mSSAOShader.setInt( "gNormal", 1 );
+    mSSAOShader.setInt( "texNoise", 2 );
+    mSSAOShader.setFloat( "noiseScale", noiseScaleVal );
+    glBindVertexArray( mQuadVAO );
+    glDrawArrays( GL_TRIANGLES, 0, 6 );
+    glBindVertexArray( 0 );
+
+    glBindFramebuffer( GL_FRAMEBUFFER, 0 );
+}
+
+void SSAORenderer::blurSSAO () {
+    int w = mHalfRes ? std::max( 1, mWidth / 2 ) : mWidth;
+    int h = mHalfRes ? std::max( 1, mHeight / 2 ) : mHeight;
+
+    glBindFramebuffer( GL_FRAMEBUFFER, mSSAOBlurFBO );
+    glViewport( 0, 0, w, h );
+    glClear( GL_COLOR_BUFFER_BIT );
+
+    mBlurShader.use();
+    glActiveTexture( GL_TEXTURE0 );
+    glBindTexture( GL_TEXTURE_2D, mSSAOTexture );
+    mBlurShader.setInt( "ssaoInput", 0 );
+    mBlurShader.setInt( "horizontal", 1 );
+    mBlurShader.setVec2( "texelSize", glm::vec2( 1.0f / float( w ), 1.0f / float( h ) ) );
+    glBindVertexArray( mQuadVAO );
+    glDrawArrays( GL_TRIANGLES, 0, 6 );
+    glBindVertexArray( 0 );
+
+    glBindFramebuffer( GL_FRAMEBUFFER, mSSAOFBO );
+    glViewport( 0, 0, w, h );
+    glClear( GL_COLOR_BUFFER_BIT );
+
+    mBlurShader.use();
+    glActiveTexture( GL_TEXTURE0 );
+    glBindTexture( GL_TEXTURE_2D, mSSAOBlurTexture );
+    mBlurShader.setInt( "ssaoInput", 0 );
+    mBlurShader.setInt( "horizontal", 0 );
+    mBlurShader.setVec2( "texelSize", glm::vec2( 1.0f / float( w ), 1.0f / float( h ) ) );
+    glBindVertexArray( mQuadVAO );
+    glDrawArrays( GL_TRIANGLES, 0, 6 );
+    glBindVertexArray( 0 );
+
+    glBindFramebuffer( GL_FRAMEBUFFER, 0 );
+}
+
+unsigned int SSAORenderer::getSSAOTextureID () const {
+    return mSSAOTexture;
+}
+
+void SSAORenderer::bindSSAOTextureToUnit ( int unit, renderer::Shader& shader, const std::string& uniformName ) const {
+    glActiveTexture( GL_TEXTURE0 + unit );
+    glBindTexture( GL_TEXTURE_2D, getSSAOTextureID() );
+    shader.setInt( uniformName, unit );
+}
+
+}   // namespace renderer