got the start of a shader that will do normal shading and shine at the same time, I will throw in a shadow map there too and it will do it all in one pass

examples/short.lua

@@ -1,5 +1,6 @@
 -- Example: Short Example
 local LightWorld = require "lib"
+local normal_map = require "lib/normal_map"
 
 function love.load()
   testShader = 0

examples/test.lua

@@ -0,0 +1,59 @@
+-- Example: normal map generation testing
+local LightWorld = require "lib"
+local util = require "lib/util"
+local normal_map = require "lib/normal_map"
+
+function love.load()
+  z = 1
+	lightWorld = LightWorld({
+    drawBackground = drawBackground,
+    drawForeground = drawForeground,
+    ambient = {55,55,55},
+    refractionStrength = 32.0,
+    reflectionVisibility = 0.75,
+  })
+
+	-- create light
+	lightMouse = lightWorld:newLight(0, 0, 255, 127, 63, 300)
+	lightMouse:setGlowStrength(0.3)
+
+  radius = 50
+	circle_canvas = love.graphics.newCanvas(radius*2, radius*2)
+  util.drawto(circle_canvas, 0, 0, 1, function()
+    love.graphics.circle('fill', radius, radius, radius) 
+  end)
+  circle_image = love.graphics.newImage(circle_canvas:getImageData()) 
+
+	local t = lightWorld:newImage(circle_image, 150, 150)
+  t:setNormalMap(normal_map.generateFlat(circle_image, "top"))
+  t:setShadowType('circle', 50)
+end
+
+function love.mousepressed(x, y, c)
+	if c == "wu" then
+    z = z + 1
+	elseif c == "wd" then
+    z = z - 1
+	end
+end
+
+function love.update(dt)
+	love.window.setTitle("Light vs. Shadow Engine (FPS:" .. love.timer.getFPS() .. ")")
+	lightMouse:setPosition(love.mouse.getX(), love.mouse.getY(), z)
+end
+
+function love.draw()
+  lightWorld:draw()
+end
+
+function drawBackground(l,t,w,h)
+  love.graphics.setColor(255, 255, 255)
+  love.graphics.rectangle("fill", l, t, w, h)
+end
+
+function drawForeground(l,t,w,h)
+  love.graphics.setColor(0, 255, 0)
+  love.graphics.circle('fill', 150,  150, 50)
+end
+
+

lib/init.lua

@@ -101,10 +101,10 @@ function light_world:draw(l,t,s)
   local w, h = love.graphics.getWidth(), love.graphics.getHeight()
   util.drawto(self.render_buffer, l, t, s, function()
     self.drawBackground(    l,t,w,h,s)
-    self:drawShadow(        l,t,w,h,s)
+    --self:drawShadow(        l,t,w,h,s)
     self.drawForeground(    l,t,w,h,s)
 		self:drawMaterial(      l,t,w,h,s)
-    self:drawShine(         l,t,w,h,s)
+    --self:drawShine(         l,t,w,h,s)
     self:drawNormalShading( l,t,w,h,s)
     self:drawGlow(          l,t,w,h,s)
     self:drawRefraction(    l,t,w,h,s)

lib/light.lua

@@ -7,6 +7,7 @@ local light = class()
 
 light.shineShader  = love.graphics.newShader(_PACKAGE.."/shaders/shine.glsl")
 light.normalShader = love.graphics.newShader(_PACKAGE.."/shaders/normal.glsl")
+light.shadowShader = love.graphics.newShader(_PACKAGE.."/shaders/shadow.glsl")
 
 function light:init(x, y, r, g, b, range)
 	self.direction = 0
@@ -32,6 +33,7 @@ function light:refresh(w, h)
 	self.shadow = love.graphics.newCanvas(w, h)
 	self.shine  = love.graphics.newCanvas(w, h)
   self.normalShader:send('screenResolution', {w, h})
+  self.shadowShader:send('screenResolution', {w, h})
 end
 
 -- set position
@@ -200,14 +202,15 @@ end
 
 function light:drawNormalShading(l,t,w,h,s, normalMap, canvas)
   if self.visible and self:inRange(l,t,w,h,s) then
-    self.normalShader:send('lightColor', {self.red / 255.0, self.green / 255.0, self.blue / 255.0})
-    self.normalShader:send("lightPosition", {(self.x + l/s) * s, (h/s - (self.y + t/s)) * s, (self.z * 10) / 255.0})
-    self.normalShader:send('lightRange',{self.range})
-    self.normalShader:send("lightSmooth", self.smooth)
-    self.normalShader:send("lightAngle", math.pi - self.angle / 2.0)
-    self.normalShader:send("lightDirection", self.direction)
-    self.normalShader:send("invert_normal", self.normalInvert == true)
-    util.drawCanvasToCanvas(normalMap, canvas, {shader = self.normalShader})
+    self.shadowShader:send('lightColor', {self.red / 255.0, self.green / 255.0, self.blue / 255.0})
+    self.shadowShader:send("lightPosition", {(self.x + l/s) * s, (h/s - (self.y + t/s)) * s, (self.z * 10) / 255.0})
+    self.shadowShader:send('lightRange',{self.range})
+    self.shadowShader:send("lightSmooth", self.smooth)
+    self.shadowShader:send("lightGlow", {1.0 - self.glowSize, self.glowStrength})
+    self.shadowShader:send("lightAngle", math.pi - self.angle / 2.0)
+    self.shadowShader:send("lightDirection", self.direction)
+    self.shadowShader:send("invert_normal", self.normalInvert == true)
+    util.drawCanvasToCanvas(normalMap, canvas, {shader = self.shadowShader})
   end
 end
 

lib/normal_map.lua

@@ -64,12 +64,10 @@ function normal_map.generateFlat(img, mode)
     color = {223, 0, 127}
   end
 
-  for i = 0, self.imgHeight - 1 do
-    for k = 0, self.imgWidth - 1 do
+  for i = 0, img:getHeight() - 1 do
+    for k = 0, img:getWidth() - 1 do
       local r, g, b, a = imgData:getPixel(k, i)
-      if a > 0 then
-        imgNormalData:setPixel(k, i, color[1], color[2], color[3], 255)
-      end
+      imgNormalData:setPixel(k, i, color[1], color[2], color[3], a)
     end
   end
 

lib/shaders/shadow.glsl

@@ -0,0 +1,90 @@
+#define PI 3.1415926535897932384626433832795
+
+extern vec2 screenResolution;
+extern vec3 lightPosition;
+extern vec3 lightColor;
+extern float lightRange;
+extern float lightSmooth;
+extern vec2 lightGlow;
+extern float lightDirection;
+extern float lightAngle;
+extern bool  invert_normal;
+
+float getHeightAt(Image texture, vec2 texture_coords) {
+  vec4 pixel = Texel(texture, texture_coords);
+  if(pixel.a > 0.0){
+    return 0.0;
+  } else {
+    return pixel.g;
+  }
+}
+
+bool is_in_shadow(Image texture, vec2 texture_coords, vec3 lightPosition, vec2 pixel_coords) {
+  vec3 coords = vec3(pixel_coords, 0.0);
+  vec3 lightVec = normalize(lightPosition - coords);
+
+  float startHeight = getHeightAt(texture, texture_coords); 
+  vec2 tx;
+  float currentHeight;
+
+  for(int i = 0; i < 100; ++i) {
+    tx = texture_coords + lightVec.xy;
+    currentHeight = getHeightAt(texture, tx);
+    if(startHeight < currentHeight){
+      return true;
+    }
+  }
+  return false;
+}
+
+vec4 effect(vec4 color, Image texture, vec2 texture_coords, vec2 pixel_coords) {
+  vec4 pixelColor = Texel(texture, texture_coords);
+
+  //if the light is a slice and the pixel is not inside
+  if(lightAngle > 0.0) {
+    float angle2 = atan(lightPosition.x - pixel_coords.x, pixel_coords.y - lightPosition.y) + PI;
+    if(lightDirection - lightAngle > 0 && lightDirection + lightAngle < PI * 2) {
+      if(angle2 < mod(lightDirection + lightAngle, PI * 2) && angle2 > mod(lightDirection - lightAngle, PI * 2)) {
+        return vec4(0.0, 0.0, 0.0, 1.0);
+      }
+    } else {
+      if(angle2 < mod(lightDirection + lightAngle, PI * 2) || angle2 > mod(lightDirection - lightAngle, PI * 2)) {
+        return vec4(0.0, 0.0, 0.0, 1.0);
+      }
+    }
+  }
+
+  vec3 normal;
+  //if on the normal map ie there is normal map data
+	if(pixelColor.a > 0.0) {
+    if(invert_normal == true) {
+      normal = normalize(vec3(pixelColor.r, 1 - pixelColor.g, pixelColor.b) * 2.0 - 1.0); 
+    } else {
+      normal = normalize(pixelColor.rgb * 2.0 - 1.0);
+    }
+  } else {
+    normal = vec3(0.0, 0.0, 1.0);
+  }
+  float dist = distance(lightPosition, vec3(pixel_coords, normal.b));
+  if(dist < lightRange) {
+    float att = clamp((1.0 - dist / lightRange) / lightSmooth, 0.0, 1.0);
+    if(pixelColor.a == 0.0) {
+      vec4 val = pixelColor;
+      val.a = 1.0;
+      if (lightGlow.x < 1.0 && lightGlow.y > 0.0) {
+        val.rgb = clamp(lightColor * pow(att, lightSmooth) + pow(smoothstep(lightGlow.x, 1.0, att), lightSmooth) * lightGlow.y, 0.0, 1.0);
+      } else {
+        val.rgb = lightColor * pow(att, lightSmooth);
+      }
+      return val;
+    } else {
+      vec3 dir = vec3((lightPosition.xy - pixel_coords.xy) / screenResolution.xy, lightPosition.z);
+      dir.x *= screenResolution.x / screenResolution.y;
+      vec3 diff = lightColor * max(dot(normalize(normal), normalize(dir)), 0.0);
+      return vec4(diff * att, 1.0);
+    }
+  } else {
+    return vec4(0.0, 0.0, 0.0, 1.0);
+  }
+}
+