From 4b2507b2f30d50c8673f33179c2b537ac83da3bf Mon Sep 17 00:00:00 2001
From: sanine <sanine.not@pm.me>
Date: Tue, 16 May 2023 22:51:17 -0500
Subject: add basic collision geom visualizations

---
 honey/ecs/render.lua | 118 ++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 97 insertions(+), 21 deletions(-)

(limited to 'honey/ecs/render.lua')

diff --git a/honey/ecs/render.lua b/honey/ecs/render.lua
index 8cca6cf..1c38692 100644
--- a/honey/ecs/render.lua
+++ b/honey/ecs/render.lua
@@ -1,4 +1,10 @@
-local ecs = require 'honey.ecs.ecs'
+local gl   = honey.gl
+local glfw = honey.glfw
+local ode  = honey.ode
+
+local ecs       = require 'honey.ecs.ecs'
+local collision = require 'honey.ecs.collision'
+local node      = require 'honey.ecs.node'
 
 local image  = require 'honey.asset.image'
 local shader = require 'honey.asset.shader'
@@ -8,16 +14,12 @@ local glm = require 'honey.glm'
 local Vec3       = glm.Vec3
 local Mat4       = glm.Mat4
 
-local gl = honey.gl
-local glfw = honey.glfw
-
-local node = require 'honey.ecs.node'
 
 local module = {}
 setmetatable(module, {__index=_G})
 setfenv(1, module)
 
---===== rendering =====--
+
 
 local function drawMesh(program, uniforms, matrices, vao, count)
 	gl.UseProgram(program)
@@ -49,6 +51,88 @@ local function drawMesh(program, uniforms, matrices, vao, count)
 end
 
 
+local function drawMeshes(db, view, projection)
+	local meshes = db:queryComponent("renderMesh")
+	for id, tbl in pairs(meshes) do
+		-- get model matrix
+		local node = db:getComponent(id, "node")
+		local model = (node and node._matrix) or Mat4():identity()
+
+		-- get shader program
+		local program = shader.get(tbl.shader)
+
+		-- get mesh
+		local vao, count = mesh.get(tbl.mesh.filename, tbl.mesh.index)
+
+		-- draw c:
+		drawMesh(program, tbl.uniforms or {}, {view=view, model=model, projection=projection}, vao, count)
+	end
+end
+
+
+local function drawGeoms(db, view, projection)
+	-- draw wireframes
+	gl.Enable(gl.CULL_FACE)
+	gl.PolygonMode(gl.FRONT_AND_BACK, gl.LINE)
+	gl.LineWidth(1)
+
+	-- shader program for all geoms
+	local program = shader.get{ vertex="builtin.basic3d.vert", fragment="builtin.color.frag" }
+	local uniforms = {
+		vec3 = {
+			color = Vec3{ 1, 0, 1 },
+		},
+	}
+
+	local query = db:queryComponent("collision")
+	for id, tbl in pairs(query) do
+		-- compute model matrix
+		local m = Mat4():identity()
+		m[1][4], m[2][4], m[3][4] = ode.GeomGetPosition(tbl._geom)
+		m[1][1], m[1][2], m[1][3],
+		m[2][1], m[2][2], m[2][3],
+		m[3][1], m[3][2], m[3][3] = ode.GeomGetRotation(tbl._geom)
+
+		local matrices = {
+			view=view,
+			projection=projection,
+			model=m,
+		}
+
+		-- get the mesh
+		if tbl.class == "sphere" then
+			m:scale(Vec3{tbl.radius, tbl.radius, tbl.radius})
+			local vao, count = mesh.get("builtin.hemisphere", 1)
+			drawMesh(program, uniforms, matrices, vao, count)
+			m:rotateX(math.pi)
+			drawMesh(program, uniforms, matrices, vao, count)
+		elseif tbl.class == "box" then
+			m:scale(Vec3{tbl.lx, tbl.ly, tbl.lz})
+			local vao, count = mesh.get("builtin.cube", 1)
+			drawMesh(program, uniforms, matrices, vao, count)
+		elseif tbl.class == "capsule" then
+			m:scale(Vec3{tbl.radius, tbl.length/2, tbl.radius})
+			local vao, count = mesh.get("builtin.tube", 1)
+			drawMesh(program, uniforms, matrices, vao, count)
+			m:scale(Vec3{1, 2*tbl.radius/tbl.length, 1})
+				:translate(Vec3{0, tbl.length/2, 0})
+			vao, count = mesh.get("builtin.hemisphere", 1)
+			drawMesh(program, uniforms, matrices, vao, count)
+			m:translate(Vec3{0, -tbl.length, 0})
+				:rotateX(math.pi)
+			drawMesh(program, uniforms, matrices, vao, count)
+		elseif tbl.class == "ray" then
+			m:scale(Vec3{0.001, 0.001, tbl.length})
+			local vao, count = mesh.get("builtin.cube", 1)
+			drawMesh(program, uniforms, matrices, vao, count)
+		end
+	end
+
+	-- switch out of wireframe mode
+	gl.PolygonMode(gl.FRONT_AND_BACK, gl.FILL)
+end
+
+
 local render = ecs.System("render", function(db, dt, p)
 	for id, camera in pairs(db:queryComponent("camera")) do
 		-- get camera's view and projection matrices
@@ -60,26 +144,18 @@ local render = ecs.System("render", function(db, dt, p)
 		else
 			view:identity()
 		end
-		
-		-- iterate over all scene meshes
-		local meshes = db:queryComponent("renderMesh")
-		for id, tbl in pairs(meshes) do
-			-- get model matrix
-			local node = db:getComponent(id, "node")
-			local model = (node and node._matrix) or Mat4():identity()
 
-			-- get shader program
-			local program = shader.get(tbl.shader)
-
-			-- get mesh
-			local vao, count = mesh.get(tbl.mesh.filename, tbl.mesh.index)
-
-			-- draw c:
-			drawMesh(program, tbl.uniforms or {}, {view=view, model=model, projection=projection}, vao, count)
+		-- optionally draw collision geoms
+		if p.drawGeoms then
+			drawGeoms(db, view, projection)
 		end
+		
+		-- render all scene meshes
+		drawMeshes(db, view, projection)
 	end
 end)
 render:addDependencies(node.system)
+render:addDependencies(collision.system)
 
 system = {render}
 
-- 
cgit v1.2.1