New textureNP implementation

This new implementation uses the previously unused viewport parameter "cota"

Src/Graphics/New3D/Model.h

@@ -200,6 +200,7 @@ struct Viewport
 	float	angle_right;
 	float	angle_top;
 	float	angle_bottom;
+	float	cota;
 
 	Mat4	projectionMatrix;		// projection matrix, we will calc this later when we have scene near/far vals
 

Src/Graphics/New3D/New3D.cpp

@@ -1061,6 +1061,8 @@ void CNew3D::RenderViewport(UINT32 addr)
 		vp->angle_bottom	= -(1.0f - io) / cw;
 		vp->angle_top		= -(0.0f - io) / cw;
 
+		vp->cota = Util::Uint32AsFloat(vpnode[0x3]);
+
 		CalcViewport(vp);
 
 		// Lighting (note that sun vector points toward sun -- away from vertex)

Src/Graphics/New3D/R3DShader.cpp

@@ -149,6 +149,8 @@ bool R3DShader::LoadShader(const char* vertexShader, const char* fragmentShader)
 	m_locHardwareStep		= glGetUniformLocation(m_shaderProgram, "hardwareStep");
 	m_locDiscardAlpha		= glGetUniformLocation(m_shaderProgram, "discardAlpha");
 
+	m_locCota				= glGetUniformLocation(m_shaderProgram, "cota");
+
 	return true;
 }
 
@@ -362,6 +364,8 @@ void R3DShader::SetViewportUniforms(const Viewport *vp)
 	glUniformMatrix4fv(m_locProjMat, 1, GL_FALSE, vp->projectionMatrix);
 
 	glUniform1i(m_locHardwareStep, vp->hardwareStep);
+
+	glUniform1f(m_locCota, vp->cota);
 }
 
 void R3DShader::SetModelStates(const Model* model)

Src/Graphics/New3D/R3DShader.h

@@ -100,6 +100,7 @@ private:
 	GLint m_locFogAttenuation;
 	GLint m_locFogAmbient;
 	GLint m_locProjMat;
+	GLint m_locCota;
 
 	// lighting / other
 	GLint m_locLighting;

Src/Graphics/New3D/R3DShaderCommon.h

@@ -119,15 +119,6 @@ ivec2 GetMicroTexturePos(int id)
 	return ivec2(xCoords[id],yCoords[id]);
 }
 
-float mip_map_level(in vec3 coordinate)
-{
-	// Real3D uses vertex coordinates rather than texel coordinates to calculate mipmap levels
-	vec3 dx_vtc = dFdx(coordinate);
-	vec3 dy_vtc = dFdy(coordinate);
-	float delta_max_sqr = max(dot(dx_vtc, dx_vtc), dot(dy_vtc, dy_vtc));
-	return log2(delta_max_sqr / (fsTextureNP * fsTextureNP)) * 0.5;			// result not clamped
-}
-
 float LinearTexLocations(int wrapMode, float size, float u, out float u0, out float u1)
 {
 	float texelSize		= 1.0 / size;
@@ -209,7 +200,7 @@ vec4 texBiLinear(usampler2D texSampler, ivec2 wrapMode, vec2 texSize, ivec2 texP
 
 vec4 GetTextureValue()
 {
-	float lod = mip_map_level(fsViewVertex);
+	float lod = -log2(gl_FragCoord.w * gl_FragCoord.w * fsLODBase);
 	float numLevels = floor(log2(min(float(baseTexInfo.z), float(baseTexInfo.w)))) - 1.0;	// r3d only generates down to 2:2 for square textures, otherwise its the min dimension
 	float fLevel = clamp(lod, 0.0, numLevels);
 
@@ -242,7 +233,7 @@ vec4 GetTextureValue()
 		ivec2 tex2Pos = GetMicroTexturePos(microTextureID);
 		tex2Data = texBiLinear(textureBank[(texturePage+1)&1], ivec2(0), ivec2(128), tex2Pos, fsTexCoord * scale, 0);
 
-		blendFactor = -(lod + microTextureMinLOD) * 0.25;
+		blendFactor = -(lod + microTextureMinLOD) * 0.5;
 		blendFactor = clamp(blendFactor, 0.0, 0.5);
 	}
 

Src/Graphics/New3D/R3DShaderQuads.h

@@ -8,6 +8,7 @@ static const char *vertexShaderR3DQuads = R"glsl(
 // uniforms
 uniform float	modelScale;
 uniform float	nodeAlpha;
+uniform float	cota;
 uniform mat4	modelMat;
 uniform mat4	projMat;
 uniform bool	translatorMap;
@@ -30,8 +31,8 @@ out VS_OUT
 	vec2	texCoord;
 	vec4	color;
 	float	fixedShade;
-	float	textureNP;
 	float	discardPoly;	// can't have varying bool (glsl spec)
+	float	LODBase;
 } vs_out;
 
 vec4 GetColour(vec4 colour)
@@ -64,7 +65,7 @@ void main(void)
 	vs_out.color    	= GetColour(inColour);
 	vs_out.texCoord		= inTexCoord;
 	vs_out.fixedShade	= inFixedShade;
-	vs_out.textureNP	= inTextureNP * modelScale;
+	vs_out.LODBase		= -vs_out.discardPoly * cota * inTextureNP;
 	gl_Position			= projMat * modelMat * inVertex;
 }
 )glsl";
@@ -83,8 +84,8 @@ in VS_OUT
 	vec2	texCoord;
 	vec4	color;
 	float	fixedShade;
-	float	textureNP;
 	float	discardPoly;	// can't have varying bool (glsl spec)
+	float	LODBase;
 } gs_in[4];
 
 out GS_OUT
@@ -99,7 +100,7 @@ out GS_OUT
 	flat vec2	texCoord[4];
 	flat vec4	color;
 	flat float	fixedShade[4];
-	flat float	textureNP;
+	flat float	LODBase;
 } gs_out;
 
 //a*b - c*d, computed in a stable fashion (Kahan)
@@ -133,7 +134,7 @@ void main(void)
 
 	// flat attributes
 	gs_out.color = gs_in[0].color;
-	gs_out.textureNP = gs_in[0].textureNP;
+	gs_out.LODBase = gs_in[0].LODBase;
 
 	// precompute crossproducts for all vertex combinations to be looked up in loop below for area computation
 	precise float cross[4][4];
@@ -238,7 +239,7 @@ in GS_OUT
 	flat vec2	texCoord[4];
 	flat vec4	color;
 	flat float	fixedShade[4];
-	flat float	textureNP;
+	flat float	LODBase;
 } fs_in;
 
 //our calculated vertex attributes from the above
@@ -247,7 +248,7 @@ vec3	fsViewNormal;
 vec2	fsTexCoord;
 float	fsFixedShade;
 vec4	fsColor;
-float	fsTextureNP;
+float	fsLODBase;
 
 //outputs
 layout(location = 0) out vec4 out0;		// opaque
@@ -332,7 +333,7 @@ void QuadraticInterpolation()
 	fsTexCoord		= vec2(0.0);
 	fsFixedShade	= 0.0;
 	fsColor			= fs_in.color;
-	fsTextureNP		= fs_in.textureNP;
+	fsLODBase		= fs_in.LODBase;
 	
 	for (int i=0; i<4; i++) {
 		fsViewVertex	+= lambda[i] * fs_in.viewVertex[i];

Src/Graphics/New3D/R3DShaderTriangles.h

@@ -8,6 +8,7 @@ static const char *vertexShaderR3D = R"glsl(
 // uniforms
 uniform float	modelScale;
 uniform float	nodeAlpha;
+uniform float	cota;
 uniform mat4	modelMat;
 uniform mat4	projMat;
 uniform bool	translatorMap;
@@ -28,7 +29,7 @@ out vec2	fsTexCoord;
 out vec4	fsColor;
 out float	fsDiscard;			// can't have varying bool (glsl spec)
 out float	fsFixedShade;
-out float	fsTextureNP;
+out float	fsLODBase;
 
 vec4 GetColour(vec4 colour)
 {
@@ -60,7 +61,7 @@ void main(void)
 	fsColor    		= GetColour(inColour);
 	fsTexCoord		= inTexCoord;
 	fsFixedShade	= inFixedShade;
-	fsTextureNP		= inTextureNP * modelScale;
+	fsLODBase		= -fsDiscard * cota * inTextureNP;
 	gl_Position		= projMat * modelMat * inVertex;
 }
 )glsl";
@@ -119,7 +120,7 @@ in  vec4	fsColor;
 in  vec2	fsTexCoord;
 in  float	fsDiscard;
 in  float	fsFixedShade;
-in	float	fsTextureNP;
+in	float	fsLODBase;
 
 //outputs
 layout(location = 0) out vec4 out0;		// opaque