_math: initial matrix/vector math library

.gitignore

@@ -0,0 +1,4 @@
+.~*
+.\#*
+\#*
+*~

_math.lua

@@ -0,0 +1,161 @@
+local ffi = require 'ffi'
+
+local sin = math.sin
+local cos = math.cos
+
+local mat4
+
+local newmat4 = function(_t)
+   -- newByteData is zero-initialized
+   local data = love.data.newByteData(16 * 4)
+   local m = ffi.cast('float*', data:getFFIPointer())
+   value = {
+      data = data,
+      m = m,
+   }
+   setmetatable(value, mat4)
+   return value
+end
+
+mat4 = {
+   __call = newmat4,
+
+   identity = function()
+      local M = newmat4()
+        M.m[0 * 4 + 0] = 1.0
+      --M.m[0 * 4 + 1] = 0.0
+      --M.m[0 * 4 + 2] = 0.0
+      --M.m[0 * 4 + 3] = 0.0
+
+      --M.m[1 * 4 + 0] = 0.0
+        M.m[1 * 4 + 1] = 1.0
+      --M.m[1 * 4 + 2] = 0.0
+      --M.m[1 * 4 + 3] = 0.0
+
+      --M.m[2 * 4 + 0] = 0.0
+      --M.m[2 * 4 + 1] = 0.0
+        M.m[2 * 4 + 2] = 1.0
+      --M.m[2 * 4 + 3] = 0.0
+
+      --M.m[3 * 4 + 0] = 0.0
+      --M.m[3 * 4 + 1] = 0.0
+      --M.m[3 * 4 + 2] = 0.0
+        M.m[3 * 4 + 3] = 1.0
+      return M
+   end,
+
+   translation = function(x, y, z)
+      local M = newmat4()
+        M.m[0 * 4 + 0] = 1.0
+      --M.m[0 * 4 + 1] = 0.0
+      --M.m[0 * 4 + 2] = 0.0
+      --M.m[0 * 4 + 3] = 0.0
+
+      --M.m[1 * 4 + 0] = 0.0
+        M.m[1 * 4 + 1] = 1.0
+      --M.m[1 * 4 + 2] = 0.0
+      --M.m[1 * 4 + 3] = 0.0
+
+      --M.m[2 * 4 + 0] = 0.0
+      --M.m[2 * 4 + 1] = 0.0
+        M.m[2 * 4 + 2] = 1.0
+      --M.m[2 * 4 + 3] = 0.0
+
+        M.m[3 * 4 + 0] = x
+        M.m[3 * 4 + 1] = y
+        M.m[3 * 4 + 2] = z
+        M.m[3 * 4 + 3] = 1.0
+      return M
+   end,
+
+   rotation_x = function(angle)
+      local sin_angle = sin(angle)
+      local cos_angle = cos(angle)
+
+      local M = newmat4()
+        M.m[0 * 4 + 0] = 1.0
+      --M.m[0 * 4 + 1] = 0.0
+      --M.m[0 * 4 + 2] = 0.0
+      --M.m[0 * 4 + 3] = 0.0
+
+      --M.m[1 * 4 + 0] = 0.0
+        M.m[1 * 4 + 1] = cos_angle
+        M.m[1 * 4 + 2] = sin_angle
+      --M.m[1 * 4 + 3] = 0.0
+
+      --M.m[2 * 4 + 0] = 0.0
+        M.m[2 * 4 + 1] = -sin_angle
+        M.m[2 * 4 + 2] = cos_angle
+      --M.m[2 * 4 + 3] = 0.0
+
+      --M.m[3 * 4 + 0] = 0.0
+      --M.m[3 * 4 + 1] = 0.0
+      --M.m[3 * 4 + 2] = 0.0
+        M.m[3 * 4 + 3] = 1.0
+      return M
+   end,
+
+   rotation_y = function(angle)
+      local sin_angle = sin(angle)
+      local cos_angle = cos(angle)
+
+      local M = newmat4()
+        M.m[0 * 4 + 0] = cos_angle
+      --M.m[0 * 4 + 1] = 0.0
+        M.m[0 * 4 + 2] = -sin_angle
+      --M.m[0 * 4 + 3] = 0.0
+
+      --M.m[1 * 4 + 0] = 0.0
+        M.m[1 * 4 + 1] = 1.0
+      --M.m[1 * 4 + 2] = 0.0
+      --M.m[1 * 4 + 3] = 0.0
+
+        M.m[2 * 4 + 0] = sin_angle
+      --M.m[2 * 4 + 1] = 0.0
+        M.m[2 * 4 + 2] = cos_angle
+      --M.m[2 * 4 + 3] = 0.0
+
+      --M.m[3 * 4 + 0] = 0.0
+      --M.m[3 * 4 + 1] = 0.0
+      --M.m[3 * 4 + 2] = 0.0
+        M.m[3 * 4 + 3] = 1.0
+      return M
+   end,
+
+   rotation_z = function(angle)
+      local sin_angle = sin(angle)
+      local cos_angle = cos(angle)
+
+      local M = newmat4()
+        M.m[0 * 4 + 0] = cos_angle
+        M.m[0 * 4 + 1] = sin_angle
+      --M.m[0 * 4 + 2] = 0.0
+      --M.m[0 * 4 + 3] = 0.0
+
+        M.m[1 * 4 + 0] = -sin_angle
+        M.m[1 * 4 + 1] = cos_angle
+      --M.m[1 * 4 + 2] = 0.0
+      --M.m[1 * 4 + 3] = 0.0
+
+      --M.m[2 * 4 + 0] = 0.0
+      --M.m[2 * 4 + 1] = 0.0
+        M.m[2 * 4 + 2] = 1.0
+      --M.m[2 * 4 + 3] = 0.0
+
+      --M.m[3 * 4 + 0] = 0.0
+      --M.m[3 * 4 + 1] = 0.0
+      --M.m[3 * 4 + 2] = 0.0
+        M.m[3 * 4 + 3] = 1.0
+      return M
+   end,
+
+   dot = function(a, b)
+      print("dot" .. tostring(a) .. tostring(b))
+   end
+}
+
+setmetatable(mat4, mat4)
+
+return {
+   mat4 = mat4
+}

main.lua

@@ -1,15 +1,25 @@
 local mesh
+local rotation
+local texture
+
+local ffi = require 'ffi'
 
 local pixelcode = [[
     #pragma language glsl3
 
-    varying vec4 PixelColor;
+    varying vec4 PixelNormal;
+    varying vec4 PixelTexture;
+
+    uniform sampler2D texture_sampler;
 
     out vec4 outData;
 
     void pixelmain()
     {
-      outData = PixelColor;
+      vec4 texColor = texture(texture_sampler, PixelTexture.xy);
+
+      float intensity = min(max(dot(vec3(1, 1, 1), PixelNormal.xyz), 0), 1);
+      outData = vec4(texColor.xyz * (0.1 + intensity * intensity), 1.0);
     }
 ]]
 
@@ -25,11 +35,13 @@ local vertexcode = [[
     uniform mat4 model;
     uniform mat4 model2;
 
-    varying vec4 PixelColor;
+    varying vec4 PixelNormal;
+    varying vec4 PixelTexture;
 
     void vertexmain()
     {
-        PixelColor = VertexNormal * 0.5 + 0.5;
+        PixelNormal = VertexNormal * 0.5 + 0.5;
+        PixelTexture = VertexTexture;
         mat4 trans = projection * view * model * model2;
         love_Position = trans * vec4(VertexPosition.xyz, 1);
     }
@@ -43,8 +55,6 @@ local vertexformat = {
    { name = 'VertexTexture', format = 'floatvec3', location = 2 },
 }
 
-local rotation
-
 function look_at()
    local m = {
       1.000000, 0.000000, 0.000000, 0.000000,
@@ -67,7 +77,7 @@ function projection()
 end
 
 function love.load(args)
-   love.window.setMode(600, 600, {depth=true})
+   love.window.setMode(1024, 1024, {depth=true})
 
    local vertexdata = love.filesystem.newFileData("position_normal_texture.vtx")
    local indexdata = love.filesystem.newFileData("index.idx")
@@ -105,6 +115,9 @@ function love.load(args)
 
    mesh = love.graphics.newMesh(attributelist, drawmode)
    mesh:setIndexBuffer(indexbuffer)
+
+  local image_data = love.image.newCompressedData('bird.dds')
+  texture = love.graphics.newTexture(image_data)
 end
 
 local rotation = 0.0
@@ -142,15 +155,29 @@ function rotate_z(t)
    }
 end
 
+function print_matrix(ptr)
+   for i=0,15 do
+      io.write(tostring(ptr[i]))
+      io.write(" ")
+      if i % 4 == 3 then
+         io.write("\n")
+      end
+   end
+end
+
+
+local math = require '_math'
+local mat4 = math.mat4
 
 function love.draw()
    local radius = 100
    local mx, my = love.mouse.getPosition()
 
    shader:send("projection", projection(1, 1))
-   shader:send("view", look_at())
+   shader:send("view", "column", mat4.translation(0, 0, -2).data)
-   shader:send("model", rotate_x(rotation))
+   shader:send("model", "column", mat4.rotation_x(rotation).data)
-   shader:send("model2", rotate_z(rotation * 0.5))
+   shader:send("model2", "column", mat4.rotation_z(rotation * 0.5).data)
+   shader:send("texture_sampler", texture)
    rotation = rotation + 0.01
    love.graphics.setShader(shader)
    love.graphics.setDepthMode("less", true)