README
¶
Shaders
About
This package contains plain vertex and fragment shaders, version 1.30 (OpenGL 3.0), for Go. It is published on https://github.com/vbsw/shaders and https://gitlab.com/vbsw/shaders.
Copyright
Copyright 2020, Vitali Baumtrok ([email protected]).
Shaders is distributed under the Boost Software License, version 1.0. (See accompanying file LICENSE or copy at http://www.boost.org/LICENSE_1_0.txt)
Shaders is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the Boost Software License for more details.
Examples
With this package:
import (
"github.com/go-gl/gl/v3.3-core/gl"
"gitlab.com/vbsw/shaders"
)
func main() {
....
shader := shaders.NewPrimitiveShader()
shader.VertexShaderID = gl.CreateShader(gl.VERTEX_SHADER)
gl.ShaderSource(shader.VertexShaderID, 1, shader.VertexShader, nil)
....
}
Standard way:
import (
"github.com/go-gl/gl/v3.3-core/gl"
)
func main() {
....
vertexShaderStr := "#version 130\nin vec3 vp;\nvoid main () {\n\tgl_Position = vec4(vp, 1.0);\n}"
shaderID := gl.CreateShader(gl.VERTEX_SHADER)
vertexShaderC, free := gl.Strs(vertexShaderStr + "\x00")
gl.ShaderSource(shaderID, 1, vertexShaderC, nil)
free()
....
}
Initialize the projection matrix:
import (
"github.com/go-gl/gl/v3.3-core/gl"
"gitlab.com/vbsw/shaders"
)
func main() {
....
shader.ProjectionLocation = gl.GetUniformLocation(shader.ProgramID, shader.ProjectionUniform)
gl.UseProgram(shader.ProgramID)
setProjection(shader.ProjectionLocation, 400, 400)
....
}
func setProjection(projectionLocation int32, width, height int) {
projectionMatrix := make([]float32, 4*4)
projectionMatrix[0] = 2.0 / float32(width)
projectionMatrix[5] = 2.0 / float32(height)
projectionMatrix[12] = -1.0
projectionMatrix[13] = -1.0
projectionMatrix[15] = 1.0
gl.UniformMatrix4fv(projectionLocation, 1, false, &projectionMatrix[0]);
}
References
Documentation
¶
Overview ¶
Package shaders contains plain vertex and fragment shaders, version 1.30 (OpenGL 3.0).
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
Types ¶
type Shader ¶
type Shader struct {
VertexShader **uint8
FragmentShader **uint8
VertexShaderID uint32
FragmentShaderID uint32
ProgramID uint32
PositionAttribute *uint8
ColorAttribute *uint8
CoordsAttribute *uint8
ProjectionUniform *uint8
ModelUniform *uint8
TextureUniform *uint8
PositionLocation int32
ColorLocation int32
CoordsLocation int32
ProjectionLocation int32
ModelLocation int32
TextureLocation int32
}
Shader is for storing shaders and their attributes.
func NewPrimitiveShader ¶
func NewPrimitiveShader() *Shader
NewPrimitiveShader returns an instance of Shader for primitive types.
Vertex shader:
#version 130
in vec3 positionIn;
in vec4 colorIn;
out vec4 fragementColor;
uniform mat4 projection = mat4(1.0);
uniform mat4 model = mat4(1.0);
void main() {
gl_Position = projection * model * vec4(positionIn, 1.0f);
fragementColor = colorIn;
}
Fragment shader:
#version 130
in vec4 fragementColor;
out vec4 color;
void main () {
color = fragementColor;
}
func NewTextureShader ¶
func NewTextureShader() *Shader
NewTextureShader returns an instance of Shader for textures.
Vertex shader:
#version 130
in vec3 positionIn;
in vec2 textureCoordsIn;
out vec2 fragmentTextureCoords;
uniform mat4 projection = mat4(1.0);
uniform mat4 model = mat4(1.0);
void main() {
gl_Position = projection * model * vec4(positionIn, 1.0f);
fragmentTextureCoords = textureCoordsIn;
}
Fragment shader:
#version 130
in vec2 fragmentTextureCoords;
out vec4 color;
uniform sampler2D imageTexture;
void main () {
color = texture(imageTexture, fragmentTextureCoords);
}
func (*Shader) FragmentShaderStr ¶
FragmentShaderStr returns fragment shader as string.
func (*Shader) VertexShaderStr ¶
VertexShaderStr returns vertex shader as string.
Source Files