ResInsight/Fwk/AppFwk/cafVizExtensions/cafInternalLegendRenderTools.cpp

//##################################################################################################
//
//   Custom Visualization Core library
//   Copyright (C) 2018- Ceetron Solutions AS
//
//   This library may be used under the terms of either the GNU General Public License or
//   the GNU Lesser General Public License as follows:
//
//   GNU General Public License Usage
//   This library is free software: you can redistribute it and/or modify
//   it under the terms of the GNU General Public License as published by
//   the Free Software Foundation, either version 3 of the License, or
//   (at your option) any later version.
//
//   This library is distributed in the hope that it will be useful, but WITHOUT ANY
//   WARRANTY; without even the implied warranty of MERCHANTABILITY or
//   FITNESS FOR A PARTICULAR PURPOSE.
//
//   See the GNU General Public License at <<http://www.gnu.org/licenses/gpl.html>>
//   for more details.
//
//   GNU Lesser General Public License Usage
//   This library is free software; you can redistribute it and/or modify
//   it under the terms of the GNU Lesser General Public License as published by
//   the Free Software Foundation; either version 2.1 of the License, or
//   (at your option) any later version.
//
//   This library is distributed in the hope that it will be useful, but WITHOUT ANY
//   WARRANTY; without even the implied warranty of MERCHANTABILITY or
//   FITNESS FOR A PARTICULAR PURPOSE.
//
//   See the GNU Lesser General Public License at <<http://www.gnu.org/licenses/lgpl-2.1.html>>
//   for more details.
//
//##################################################################################################

#include "cafInternalLegendRenderTools.h"
#include "cvfOpenGL.h"
#include "cvfRenderStateDepth.h"
#include "cvfRenderStateLine.h"
#include "cvfRenderStateBlending.h"
#include "cvfShaderProgram.h"
#include "cvfOpenGLContext.h"
#include "cvfOpenGLResourceManager.h"
#include <array>
#include "cvfUniform.h"
#include "cvfRenderState_FF.h"

using namespace cvf;

namespace caf
{
//--------------------------------------------------------------------------------------------------
/// Render a semi transparent background frame
//--------------------------------------------------------------------------------------------------
void InternalLegendRenderTools::renderBackgroundUsingShaders(OpenGLContext* oglContext,
                                                     const MatrixState& matrixState,
                                                     const Vec2f& size,
                                                     const Color4f& backgroundColor,
                                                     const Color4f& backgroundFrameColor)
{
    CVF_CALLSITE_OPENGL(oglContext);

    RenderStateDepth depth(false);
    depth.applyOpenGL(oglContext);

    RenderStateLine line(1.0f);
    line.applyOpenGL(oglContext);

    RenderStateBlending blend;
    blend.configureTransparencyBlending();
    blend.applyOpenGL(oglContext);

    // Shader program

    ref<ShaderProgram> shaderProgram = oglContext->resourceManager()->getLinkedUnlitColorShaderProgram(oglContext);
    CVF_TIGHT_ASSERT(shaderProgram.notNull());

    if (shaderProgram->useProgram(oglContext))
    {
        shaderProgram->clearUniformApplyTracking();
        shaderProgram->applyFixedUniforms(oglContext, matrixState);
    }

    std::array<Vec3f, 4> vertexArray ={
        Vec3f(1       ,        1, 0.0f),
        Vec3f(size.x(),        1, 0.0f),
        Vec3f(size.x(), size.y(), 0.0f),
        Vec3f(1       , size.y(), 0.0f),
    };


    glBindBuffer(GL_ARRAY_BUFFER, 0);
    glEnableVertexAttribArray(ShaderProgram::VERTEX);
    glVertexAttribPointer(ShaderProgram::VERTEX, 3, GL_FLOAT, GL_FALSE, 0, vertexArray.data());

    // Draw frame background

    UniformFloat backgroundColorUniform("u_color", backgroundColor);
    shaderProgram->applyUniform(oglContext, backgroundColorUniform);

    // Triangle indices for the frame background

    static const ushort backgroundTriangleIndices[] = { 0, 1, 2,  2, 3, 0};

    glDrawRangeElements(GL_TRIANGLES, 0, 3, 6, GL_UNSIGNED_SHORT, backgroundTriangleIndices);


    // Draw frame border lines

    UniformFloat uniformColor("u_color", backgroundFrameColor);
    shaderProgram->applyUniform(oglContext, uniformColor);

    static const ushort frameLineIndices[] = { 0, 1,
                                               1, 2,
                                               2, 3,
                                               3, 0 };

    glDrawRangeElements(GL_LINES, 0, 3, 8, GL_UNSIGNED_SHORT, frameLineIndices);

    glDisableVertexAttribArray(ShaderProgram::VERTEX);

    CVF_TIGHT_ASSERT(shaderProgram.notNull());
    shaderProgram->useNoProgram(oglContext);

    // Reset render states
    RenderStateDepth resetDepth;
    resetDepth.applyOpenGL(oglContext);

    RenderStateLine resetLine;
    resetLine.applyOpenGL(oglContext);

    RenderStateBlending resetblend;
    resetblend.applyOpenGL(oglContext);

    CVF_CHECK_OGL(oglContext);
}

//--------------------------------------------------------------------------------------------------
/// Draw a background rectangle using OGL 1.1 compatibility
//--------------------------------------------------------------------------------------------------
void InternalLegendRenderTools::renderBackgroundImmediateMode(OpenGLContext* oglContext,
                                                      const Vec2f& size,
                                                      const Color4f& backgroundColor,
                                                      const Color4f& backgroundFrameColor)
{
    RenderStateDepth depth(false);
    depth.applyOpenGL(oglContext);

    RenderStateLighting_FF lighting(false);
    lighting.applyOpenGL(oglContext);

    RenderStateBlending blend;
    blend.configureTransparencyBlending();
    blend.applyOpenGL(oglContext);

    // Frame vertices

    std::array<Vec3f, 4> vertexArray = {
        Vec3f(1       ,        1, 0.0f),
        Vec3f(size.x(),        1, 0.0f),
        Vec3f(size.x(), size.y(), 0.0f),
        Vec3f(1       , size.y(), 0.0f),
    };


    glColor4fv(backgroundColor.ptr());
    glBegin(GL_TRIANGLE_FAN);
    glVertex3fv(vertexArray[0].ptr());
    glVertex3fv(vertexArray[1].ptr());
    glVertex3fv(vertexArray[2].ptr());
    glVertex3fv(vertexArray[3].ptr());
    glEnd();

    // Render Line around

    {
        glColor4fv(backgroundFrameColor.ptr());
        glBegin(GL_LINES);
        glVertex3fv(vertexArray[0].ptr());
        glVertex3fv(vertexArray[1].ptr());
        glVertex3fv(vertexArray[1].ptr());
        glVertex3fv(vertexArray[2].ptr());
        glVertex3fv(vertexArray[2].ptr());
        glVertex3fv(vertexArray[3].ptr());
        glVertex3fv(vertexArray[3].ptr());
        glVertex3fv(vertexArray[0].ptr());
        glEnd();
    }

    // Reset render states

    RenderStateLighting_FF resetLighting;
    resetLighting.applyOpenGL(oglContext);
    RenderStateDepth resetDepth;
    resetDepth.applyOpenGL(oglContext);
    RenderStateBlending resetblend;
    resetblend.applyOpenGL(oglContext);
    CVF_CHECK_OGL(oglContext);
}


}