////  GLBackendTexture.cpp//  libraries/gpu/src/gpu////  Created by Sam Gateau on 1/19/2015.//  Copyright 2014 High Fidelity, Inc.////  Distributed under the Apache License, Version 2.0.//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html//#include "GLBackend.h"#include "GLShared.h"#include "GLFramebuffer.h" #include <QtGui/QImage> using namespace gpu;using namespace gpu::gl; void GLBackend::syncOutputStateCache() {    GLint currentFBO;    glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &currentFBO);     _output._drawFBO = currentFBO;    reset(_output._framebuffer);} void GLBackend::resetOutputStage() {    if (valid(_output._framebuffer)) {        reset(_output._framebuffer);        _output._drawFBO = 0;        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);    }     glEnable(GL_FRAMEBUFFER_SRGB);} void GLBackend::do_setFramebuffer(const Batch& batch, size_t paramOffset) {    const auto& framebuffer = batch._framebuffers.get(batch._params[paramOffset]._uint);    setFramebuffer(framebuffer);} void GLBackend::do_setFramebufferSwapChain(const Batch& batch, size_t paramOffset) {    auto swapChain = std::static_pointer_cast<FramebufferSwapChain>(batch._swapChains.get(batch._params[paramOffset]._uint));    if (swapChain) {        auto index = batch._params[paramOffset + 1]._uint;        const auto& framebuffer = swapChain->get(index);        setFramebuffer(framebuffer);    }} void GLBackend::setFramebuffer(const FramebufferPointer& framebuffer) {    if (!compare(_output._framebuffer, framebuffer)) {        auto newFBO = getFramebufferID(framebuffer);        if (_output._drawFBO != newFBO) {            _output._drawFBO = newFBO;            glBindFramebuffer(GL_DRAW_FRAMEBUFFER, newFBO);        }        assign(_output._framebuffer, framebuffer);    }} void GLBackend::do_advance(const Batch& batch, size_t paramOffset) {    auto ringbuffer = batch._swapChains.get(batch._params[paramOffset]._uint);    if (ringbuffer) {        ringbuffer->advance();    }} void GLBackend::do_clearFramebuffer(const Batch& batch, size_t paramOffset) {    if (_stereo.isStereo() && !_pipeline._stateCache.flags.scissorEnable) {        qWarning("Clear without scissor in stereo mode");    }     uint32 masks = batch._params[paramOffset + 7]._uint;    Vec4 color;    color.x = batch._params[paramOffset + 6]._float;    color.y = batch._params[paramOffset + 5]._float;    color.z = batch._params[paramOffset + 4]._float;    color.w = batch._params[paramOffset + 3]._float;    float depth = batch._params[paramOffset + 2]._float;    int stencil = batch._params[paramOffset + 1]._int;    int useScissor = batch._params[paramOffset + 0]._int;     GLuint glmask = 0;    bool restoreStencilMask = false;    uint8_t cacheStencilMask = 0xFF;    if (masks & Framebuffer::BUFFER_STENCIL) {        glClearStencil(stencil);        glmask |= GL_STENCIL_BUFFER_BIT;         cacheStencilMask = _pipeline._stateCache.stencilActivation.getWriteMaskFront();        if (cacheStencilMask != 0xFF) {            restoreStencilMask = true;            glStencilMask( 0xFF);        }    }     bool restoreDepthMask = false;    if (masks & Framebuffer::BUFFER_DEPTH) {        glClearDepthf(depth);        glmask |= GL_DEPTH_BUFFER_BIT;                bool cacheDepthMask = _pipeline._stateCache.depthTest.getWriteMask();        if (!cacheDepthMask) {            restoreDepthMask = true;            glDepthMask(GL_TRUE);        }    }     std::vector<GLenum> drawBuffers;    auto framebuffer = acquire(_output._framebuffer);    if (masks & Framebuffer::BUFFER_COLORS) {        if (framebuffer) {            for (unsigned int i = 0; i < Framebuffer::MAX_NUM_RENDER_BUFFERS; i++) {                if (masks & (1 << i)) {                    drawBuffers.push_back(GL_COLOR_ATTACHMENT0 + i);                }            }             if (!drawBuffers.empty()) {                glDrawBuffers((GLsizei)drawBuffers.size(), drawBuffers.data());                glClearColor(color.x, color.y, color.z, color.w);                glmask |= GL_COLOR_BUFFER_BIT;                            (void) CHECK_GL_ERROR();            }        } else {            glClearColor(color.x, color.y, color.z, color.w);            glmask |= GL_COLOR_BUFFER_BIT;        }                // Force the color mask cache to WRITE_ALL if not the case        do_setStateColorWriteMask(State::ColorMask::WRITE_ALL);    }     // Apply scissor if needed and if not already on    bool doEnableScissor = (useScissor && (!_pipeline._stateCache.flags.scissorEnable));    if (doEnableScissor) {        glEnable(GL_SCISSOR_TEST);    }     // Clear!    glClear(glmask);     // Restore scissor if needed    if (doEnableScissor) {        glDisable(GL_SCISSOR_TEST);    }     // Restore Stencil write mask    if (restoreStencilMask) {        glStencilMask(cacheStencilMask);    }     // Restore write mask meaning turn back off    if (restoreDepthMask) {        glDepthMask(GL_FALSE);    }        // Restore the color draw buffers only if a frmaebuffer is bound    if (framebuffer && !drawBuffers.empty()) {        auto glFramebuffer = syncGPUObject(*framebuffer);        if (glFramebuffer) {            glDrawBuffers((GLsizei)glFramebuffer->_colorBuffers.size(), glFramebuffer->_colorBuffers.data());        }    }     (void) CHECK_GL_ERROR();} void GLBackend::downloadFramebuffer(const FramebufferPointer& srcFramebuffer, const Vec4i& region, QImage& destImage) {    auto readFBO = getFramebufferID(srcFramebuffer);    if (srcFramebuffer && readFBO) {        if ((srcFramebuffer->getWidth() < (region.x + region.z)) || (srcFramebuffer->getHeight() < (region.y + region.w))) {          qCWarning(gpugllogging) << "GLBackend::downloadFramebuffer : srcFramebuffer is too small to provide the region queried";          return;        }    }     if ((destImage.width() < region.z) || (destImage.height() < region.w)) {          qCWarning(gpugllogging) << "GLBackend::downloadFramebuffer : destImage is too small to receive the region of the framebuffer";          return;    }     GLenum format = GL_BGRA;    auto backendApi = hifi::properties::getGraphicsAPI();    if (backendApi == hifi::properties::GraphicsAPI::GLES32) {        format = GL_RGBA;    }    if (destImage.format() != QImage::Format_ARGB32) {          qCWarning(gpugllogging) << "GLBackend::downloadFramebuffer : destImage format must be FORMAT_ARGB32 to receive the region of the framebuffer";          return;    }     glBindFramebuffer(GL_READ_FRAMEBUFFER, getFramebufferID(srcFramebuffer));    glReadPixels(region.x, region.y, region.z, region.w, format, GL_UNSIGNED_BYTE, destImage.bits());    glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);     (void) CHECK_GL_ERROR();}