I'm trying to port a game of mine from android to the pc(linux), the following code is used to draw a 2d sprite, and works in android,

this is the render code, shader is a wrapper class for shader handling.

	GLfloat verts[] =
	{
		position.x, position.y + size.y, 0.0f, src.left, src.bottom,
		position.x, position.y, 0.0f, src.left, src.top,
		position.x + size.x, position.y + size.y, 0.0f, src.right, src.bottom,
		position.x + size.x, position.y, 0.0f, src.right, src.top
	};

	GLushort indices[] = {0, 2, 1, 1, 2, 3};

	Matrix4f p;

	if(rotation != 0.0f)
	{
		Matrix4f rotmat, trans;

		trans.Translate(Vector3f(-rotpos.x, -rotpos.y, 0.0f));
		rotmat.RotationZ(RAD(rotation));
		rotmat = trans * rotmat;
		trans.Translate(Vector3f(rotpos.x, rotpos.y, 0.0f));
		p = trans * rotmat;
	}

	Matrix4f mpv = Graphics::GetOrtho();
	p = mpv * p;

	shader->Use();

	int loc = shader->GetUniformLocation("intexture");
	texture->Use();
	shader->Uniform1i(loc, 0);


	loc = shader->GetUniformLocation("mpv");
	shader->UniformMatrix(loc, p);
	
	loc = shader->GetUniformLocation("color");
	shader->UniformVec4(loc, color);

	glBindBuffer(GL_ARRAY_BUFFER, 0);
	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);

	glEnableVertexAttribArray(0);
	glEnableVertexAttribArray(1);

	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(float) * 5, verts);
	glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, sizeof(float) * 5, &verts[3]);

	glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, indices);

vertex shader

#version 410

attribute vec4 vPosition;
attribute vec2 vTexCoord;

varying vec2 fTexCoord;

uniform mat4 mpv;
uniform vec4 color;

void main()
{
	gl_Position = vPosition * mpv;
	fTexCoord = vTexCoord;
}

fragment shader

#version 410

//precision mediump float;

varying vec2 fTexCoord;

uniform sampler2D intexture;
uniform vec4 color;

void main()
{
	gl_FragColor = texture2D(intexture, fTexCoord) * color;	
}

Any help would be gratefull.

Thanks.

opengl logs dont show any shader errors, ive made changes but still nothing.

#version 410

in vec4 vPosition;
in vec2 vTexCoord;

out vec2 fTexCoord;

uniform mat4 mpv;
uniform vec4 color;

void main()
{
	gl_Position = vPosition * mpv;
	fTexCoord = vTexCoord;
}

#version 410

//precision mediump float;

in vec2 fTexCoord;
out vec4 output_color;

uniform sampler2D intexture;
uniform vec4 color;

void main()
{
	output_color = (texture(intexture, fTexCoord) * color).rgba; 
}

thanks.

Your CPU side code does not show what values is being assigned to the uniform associated "color" in the shader.

I'm assuming

loc = shader->GetUniformLocation("color"); shader->UniformVec4(loc, color);

set the uniform values, in which case what are the values in color ?

Oh, just noticed that you also do "gl_Position = vPosition * mpv", it should probably be "gl_Position = mpv * vPosition". And by opengl logs, do you mean that you're using glGetProgramInfoLog? It really didn't tell any warnings or errors about those?

yes nothing from glGetProgramInfoLog.

Your CPU side code does not show what values is being assigned to the uniform associated "color" in the shader.

I'm assuming

loc = shader->GetUniformLocation("color"); shader->UniformVec4(loc, color);

set the uniform values, in which case what are the values in color ?

color = Vector4f(1.0f, 1.0f, 1.0f, 1.0f);

yes those read and set the location of the Uniforms

and heres the locations set for the attributes.

		shader = Resource::Instance()->GetAssetShader(L"textureshader");
		shader->BindAttribLocation(0, "vPosition");
		shader->BindAttribLocation(1, "vTexCoord");
		shader->Link();

seems like I’ve made some progress, I was rendering without buffers in gles, seems like I cant do that in gl.

thanks for your help all.