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#pragma once
#include "View.h"
#include "math/AABB.h"
#include "math/Matrix4.h"
namespace render
{
class TextureToolView :
public View
{
public:
/**
* Construct the orthographic projection matrix such that the given
* texture space bounds are visible.
*
* Only the XY coordinates of the bounds are considered, Z is ignored.
*/
void constructFromTextureSpaceBounds(const AABB& texSpaceAABB, std::size_t deviceWidth, std::size_t deviceHeight)
{
// Set up the orthographic projection matrix to [b,l..t,r] => [-1,-1..+1,+1]
// with b,l,t,r set to values centered at origin
double left = -texSpaceAABB.extents.x();
double right = texSpaceAABB.extents.x();
double top = texSpaceAABB.extents.y();
double bottom = -texSpaceAABB.extents.y();
auto rMinusL = right - left;
auto rPlusL = right + left;
auto tMinusB = top - bottom;
auto tPlusB = top + bottom;
auto projection = Matrix4::getIdentity();
projection[0] = 2.0f / rMinusL;
projection[5] = 2.0f / tMinusB;
projection[10] = -1;
projection[12] = rPlusL / rMinusL;
projection[13] = tPlusB / tMinusB;
projection[14] = 0;
auto modelView = Matrix4::getIdentity();
// We have to invert the Y axis to have the negative tex coords in the upper quadrants
modelView.xx() = 1;
modelView.yy() = -1;
// Shift the visible UV space such that it is centered around origin before projecting it
modelView.tx() = -texSpaceAABB.origin.x();
modelView.ty() = texSpaceAABB.origin.y();
construct(projection, modelView, deviceWidth, deviceHeight);
}
};
}
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