Method DrawGrid

Engine/source/EtRendering/Extensions/DebugRenderer.cpp:150–297

}

void DebugRenderer::DrawGrid(Camera const& camera, float pixelSpacingRad)
{
#if defined(ET_DEBUG)
	vec3 camPos = camera.GetPosition();
		
	//max draw distance of the grid
	constexpr float falloffAngle = math::radians(75.f);
	float distLimit = sqrt(pow(camera.GetFarPlane(), 2) - camPos.y*camPos.y);
	float maxDist = std::min(tan(falloffAngle)*std::abs(camPos.y), distLimit);

	//figure out the spacing of lines
	static const float unit = 1;

	float spacing = tan((camera.GetFOV() / Viewport::GetCurrentViewport()->GetDimensions().x)*pixelSpacingRad)*std::abs(camPos.y);
	int32 digitCount = 0;
	float num = abs(spacing);
	while (num >= unit)
	{
		num /= 10;
		digitCount++;
	}
	int32 spacingLower = 10 ^ (digitCount);
	int32 spacingHigher = spacingLower * 10;

	//how many lines do we draw?
	int32 linesDrawn = (int32)(maxDist / (float)spacingLower);

	vec2 floorPos = vec2(camPos.x, camPos.z);//height is 0
	ivec2 lineIdx = math::vecCast<int32>((floorPos / (float)spacingLower));
	vec2 basePos = math::vecCast<float>(lineIdx) * (float)spacingLower;

	//Line thickness and alpha
	constexpr float thicknessHigher = 5;
	constexpr float thicknessLower = 2;

	float maxAlpha = 0.5f;
	float fade = (spacing - spacingLower) / (spacingHigher - spacingLower);
	fade = 1;
	float thickness = thicknessLower + ((thicknessHigher - thicknessLower)*fade);

	const vec3 greyCol(0.75f);
	const vec3 redCol(1, 0, 0);
	const vec3 blueCol(0, 0, 1);

	//Create the lines
	std::vector<LineVertex> normalLines;
	std::vector<LineVertex> thickLines;

	//lateral (X)
	for (int32 i = lineIdx.y - linesDrawn; i < lineIdx.y + linesDrawn; ++i)
	{
		vec2 pos = math::vecCast<float>(ivec2(lineIdx.x, i)) * (float)spacingLower;
		float lineFalloff = 1 - (abs(pos.y - basePos.y) / maxDist);
		float  lineDist = sin(math::PI_DIV2*lineFalloff)*maxDist;
		vec3 p0 = vec3(pos.x-lineDist, 0, pos.y);
		vec3 p1 = vec3(pos.x, 0, pos.y);
		vec3 p2 = vec3(pos.x+lineDist, 0, pos.y);