40 lines
1.0 KiB
V
40 lines
1.0 KiB
V
module gg
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import (
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gl
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gx
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math
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)
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fn arc_vertices(x, y, r, start_angle, end_angle f32, segments int) []f32 {
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mut vertices := []f32
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start_rads := start_angle * 0.0174533 // deg -> rad approx
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end_rads := end_angle * 0.0174533
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increment := (end_rads - start_rads) / segments
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vertices << [x + f32(math.cos(start_rads)) * r, y + f32(math.sin(start_rads)) * r] !
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mut i := 1
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for i < segments {
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theta := f32(i) * increment + start_rads
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vertices << [x + f32(math.cos(theta)) * r, y + f32(math.sin(theta)) * r] !
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i++
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}
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vertices << [x + f32(math.cos(end_rads)) * r, y + f32(math.sin(end_rads)) * r] !
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return vertices
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}
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fn (ctx &GG) use_color_shader(color gx.Color) {
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ctx.shader.set_int('has_texture', 0)
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C.glDeleteBuffers(1, &ctx.vao)
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C.glDeleteBuffers(1, &ctx.vbo)
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ctx.shader.use()
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ctx.shader.set_color('color', color)
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}
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fn (ctx &GG) bind_vertices(vertices []f32) {
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gl.bind_vao(ctx.vao)
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gl.set_vbo(ctx.vbo, vertices, C.GL_STATIC_DRAW)
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gl.vertex_attrib_pointer(0, 2, C.GL_FLOAT, false, 2, 0)
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gl.enable_vertex_attrib_array(0)
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gl.bind_vao(ctx.vao)
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}
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