public static void DrawLine(WebGLRenderingContext gl, WebGLProgram program, RGBAColour colour, int x0, int y0, int x1, int y1) { gl.UseProgram(program); var positionCoords = new float[] { x0, y0, x1, y1 }; /* Add the components of the colour twice (one for each vertex). */ var colours = new float[] { colour.R, colour.G, colour.B, colour.A, colour.R, colour.G, colour.B, colour.A }; var matrixLocation = gl.GetUniformLocation(program, "u_matrix"); /* Load the colour into a buffer and bind to shader attribute. */ var colourBuffer = gl.CreateBuffer(); var colourLocation = gl.GetAttribLocation(program, "a_color"); gl.BindBuffer(gl.ARRAY_BUFFER, colourBuffer); gl.BufferData(gl.ARRAY_BUFFER, new Float32Array(colours), gl.STATIC_DRAW); gl.VertexAttribPointer(colourLocation, 4, gl.FLOAT, false, 0, 0); gl.EnableVertexAttribArray(colourLocation); /* Load the line endpoints into a buffer and bind to shader attribute. */ var vertexBuffer = gl.CreateBuffer(); var positionLocation = gl.GetAttribLocation(program, "a_position"); gl.BindBuffer(gl.ARRAY_BUFFER, vertexBuffer); gl.BufferData(gl.ARRAY_BUFFER, new Float32Array(positionCoords), gl.STATIC_DRAW); gl.VertexAttribPointer(positionLocation, 2, gl.FLOAT, false, 0, 0); gl.EnableVertexAttribArray(positionLocation); /* Set up projection matrix and translate to screen origin. */ var matrix = CameraHelpers.Orthographic(0, gl.Canvas.Width, gl.Canvas.Height, 0, -1, 1); gl.UniformMatrix4fv(matrixLocation, false, matrix.ToArray()); matrix = matrix.Translate(x0 / (float)gl.Canvas.Width * 2, -y0 / (float)gl.Canvas.Height * 2, 0); gl.DrawArrays(gl.LINES, 0, 2); gl.BindBuffer(gl.ARRAY_BUFFER, null); }
public void InitShaders() { var fragmentShader = this.GetShader(gl, "shader-fs"); var vertexShader = this.GetShader(gl, "shader-vs"); var shaderProgram = gl.CreateProgram().As <WebGLProgram>(); if (shaderProgram.Is <int>()) { Global.Alert("Could not initialise program"); } gl.AttachShader(shaderProgram, vertexShader); gl.AttachShader(shaderProgram, fragmentShader); gl.LinkProgram(shaderProgram); if (!gl.GetProgramParameter(shaderProgram, gl.LINK_STATUS).As <bool>()) { Global.Alert("Could not initialise shaders"); } gl.UseProgram(shaderProgram); this.vertexPositionAttribute = gl.GetAttribLocation(shaderProgram, "aVertexPosition"); this.vertexNormalAttribute = gl.GetAttribLocation(shaderProgram, "aVertexNormal"); this.textureCoordAttribute = gl.GetAttribLocation(shaderProgram, "aTextureCoord"); gl.EnableVertexAttribArray(this.vertexPositionAttribute); gl.EnableVertexAttribArray(this.vertexNormalAttribute); gl.EnableVertexAttribArray(this.textureCoordAttribute); this.pMatrixUniform = gl.GetUniformLocation(shaderProgram, "uPMatrix"); this.mvMatrixUniform = gl.GetUniformLocation(shaderProgram, "uMVMatrix"); this.nMatrixUniform = gl.GetUniformLocation(shaderProgram, "uNMatrix"); this.samplerUniform = gl.GetUniformLocation(shaderProgram, "uSampler"); this.useLightingUniform = gl.GetUniformLocation(shaderProgram, "uUseLighting"); this.ambientColorUniform = gl.GetUniformLocation(shaderProgram, "uAmbientColor"); this.lightingDirectionUniform = gl.GetUniformLocation(shaderProgram, "uLightingDirection"); this.directionalColorUniform = gl.GetUniformLocation(shaderProgram, "uDirectionalColor"); this.alphaUniform = gl.GetUniformLocation(shaderProgram, "uAlpha"); this.program = shaderProgram; }
public static void DrawImage(WebGLRenderingContext gl, TextureInfo textureInfo, WebGLProgram program, int xSrc, int ySrc, int srcWidth, int srcHeight, int xDest, int yDest, int destWidth, int destHeight) { gl.UseProgram(program); var positionLocation = gl.GetAttribLocation(program, "a_position"); var texCoordLocation = gl.GetAttribLocation(program, "a_texcoord"); var matrixLocation = gl.GetUniformLocation(program, "u_matrix"); var textureLocation = gl.GetUniformLocation(program, "u_texture"); /* Create a buffer to hold the position coordinates. */ var positionBuffer = gl.CreateBuffer(); var positionCoords = new float[] { 0, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1 }; gl.BindBuffer(gl.ARRAY_BUFFER, positionBuffer); gl.BufferData(gl.ARRAY_BUFFER, new Float32Array(positionCoords), gl.STATIC_DRAW); /* Create a buffer to hold the texture coordinates. */ var sx = xSrc / (float)textureInfo.Width.Value; var sy = ySrc / (float)textureInfo.Height.Value; var sw = srcWidth / (float)textureInfo.Width.Value; var sh = srcHeight / (float)textureInfo.Height.Value; var texBuffer = gl.CreateBuffer(); var texCoords = new float[] { 0 + sx, 0 + sy, 0 + sx, sh + sy, sw + sx, 0 + sy, sw + sx, 0 + sy, 0 + sx, sh + sy, sw + sx, sh + sy }; gl.BindBuffer(gl.ARRAY_BUFFER, texBuffer); gl.BufferData(gl.ARRAY_BUFFER, new Float32Array(texCoords), gl.STATIC_DRAW); gl.BindTexture(gl.TEXTURE_2D, textureInfo.Texture); gl.BindBuffer(gl.ARRAY_BUFFER, positionBuffer); gl.EnableVertexAttribArray(positionLocation); gl.VertexAttribPointer(positionLocation, 2, gl.FLOAT, false, 0, 0); gl.BindBuffer(gl.ARRAY_BUFFER, texBuffer); gl.EnableVertexAttribArray(texCoordLocation); gl.VertexAttribPointer(texCoordLocation, 2, gl.FLOAT, false, 0, 0); /* Create an standard orthographic projection to transform our coordinates by and bind to our shader uniform. */ var matrix = CameraHelpers.Orthographic(0, gl.Canvas.Width, gl.Canvas.Height, 0, -1, 1); matrix = matrix.Translate(xDest / (float)gl.Canvas.Width * 2, -yDest / (float)gl.Canvas.Height * 2, 0); matrix = matrix.Scale(destWidth, destHeight, 1); gl.UniformMatrix4fv(matrixLocation, false, matrix.ToArray()); gl.Uniform1i(textureLocation, 0); /* 6 points per image rendered as two triangles. */ gl.DrawArrays(gl.TRIANGLES, 0, 6); gl.BindBuffer(gl.ARRAY_BUFFER, null); }