VBO and glGenBuffers

BlitzMax Forums/OpenGL Module/VBO and glGenBuffers

FBEpyon

(Posted 2014) [#1]

Hello,

Can someone tell me if this is correct for the VBOs

Type tmesh

	Field varray:Float[]
	field vbuffer:Int

	Method Init:tmesh(v:Float[])
		varray = v[..]
		glGenBuffers(1, VarPtr(vbuffer))
		glBindBuffer(GL_ARRAY_BUFFER, vbuffer)
		glBufferData(GL_ARRAY_BUFFER, SizeOf(varray), varray, GL_DYNAMIC_DRAW)
	End Method

	Method Draw:tMesh()
		glBindBuffer(GL_VERTEX_ARRAY, vbuffer)
		glVertexPointer(3, GL_FLOAT, 0, Int Ptr 0)
		glEnableClientState(GL_VERTEX_ARRAY)
		glDrawAarrays(GL_TRIANGLES, 0, 3)
		glDisableClientState(GL_VERTEX_ARRAY)
		glFlush()
	End Method

End Type

Function CreateMesh:tMesh(vertex:Float[], mesh:tMesh=Null)
	If mesh = null then mesh = New tMesh.Init(vertex[..])
	Return mesh
End Function

SetGraphicsDriver GLGraphicsDriver()

Graphics 800,600

arraytest:Float[] = [1.0,1.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0]

Global meshtest:tMesh = CreateMesh(arraytest)

While Not KeyHit(KEY_ESCAPE)

	glClear GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT

	meshtest.Draw()

	Flip

Wend
End

This is the link I used:
Vertex Buffer Object

Thanks,

FBEpyon

KronosUK

(Posted 2014) [#2]

This seems to work


Type TMesh

	Field varray:Float[]
	Field vbuffer:Int

	Method Init:TMesh(v:Float[])
		varray = v
		glGenBuffers(1, Varptr vbuffer)
		glBindBuffer(GL_ARRAY_BUFFER, vbuffer)
		glBufferData(GL_ARRAY_BUFFER, SizeOf(varray), varray, GL_DYNAMIC_DRAW)
	End Method

	Method Draw:TMesh()
		glBindBuffer(GL_VERTEX_ARRAY, vbuffer)
		glVertexPointer(3, GL_FLOAT, 0, Int Ptr 0)
		glEnableClientState(GL_VERTEX_ARRAY)
		glDrawarrays(GL_TRIANGLES, 0, 3)
		glDisableClientState(GL_VERTEX_ARRAY)
		glFlush()
	End Method

End Type

Function CreateMesh:TMesh(vertex:Float[])
	Local mesh:TMesh = New TMesh
	mesh.init(vertex)
	Return mesh
End Function

SetGraphicsDriver GLGraphicsDriver()

Graphics 800,600
glewinit()

Local arraytest:Float[] = [1.0,1.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0]

Global meshtest:TMesh = CreateMesh(arraytest)

While Not KeyHit(KEY_ESCAPE)

	glClear GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT

	meshtest.Draw()

	Flip

Wend
End

*	(Posted 2014) [#3]

Interesting stuff makes me want to have a crack at max again :)

FBEpyon

(Posted 2014) [#4]

Thanks,

I wasn't sure if anyone else was having luck with it, I will work on cranking out more things in the next few weeks..

I wanted to work with pure OpenGl now instead of using the mods out there.

I noticed you added in the glewinit() that would explain my issues..

I also wrote a Martix and Vector Class.. so I will be adding in the rotation here soon.. just need to figure that out, most people use shaders when you are working with opengl 3.0 and higher you have to.