diff options
Diffstat (limited to 'system/shaders/GLES/2.0/gles_shader_clip.vert')
-rw-r--r-- | system/shaders/GLES/2.0/gles_shader_clip.vert | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/system/shaders/GLES/2.0/gles_shader_clip.vert b/system/shaders/GLES/2.0/gles_shader_clip.vert new file mode 100644 index 0000000000..513a24456c --- /dev/null +++ b/system/shaders/GLES/2.0/gles_shader_clip.vert @@ -0,0 +1,39 @@ +/* + * Copyright (C) 2024 Team Kodi + * This file is part of Kodi - https://kodi.tv + * + * SPDX-License-Identifier: GPL-2.0-or-later + * See LICENSES/README.md for more information. + */ + +#version 100 + +attribute vec4 m_attrpos; +attribute vec4 m_attrcol; +attribute vec4 m_attrcord0; +attribute vec4 m_attrcord1; +varying vec4 m_cord0; +varying vec4 m_cord1; +varying vec4 m_colour; +uniform mat4 m_matrix; +uniform vec4 m_shaderClip; +uniform vec4 m_cordStep; + +// this shader can be used in cases where clipping via glScissor() is not +// possible (e.g. when rotating). it can't discard triangles, but it may +// degenerate them. + +void main() +{ + // limit the vertices to the clipping area + vec4 position = m_attrpos; + position.xy = clamp(position.xy, m_shaderClip.xy, m_shaderClip.zw); + gl_Position = m_matrix * position; + + // correct texture coordinates for clipped vertices + vec2 clipDist = m_attrpos.xy - position.xy; + m_cord0.xy = m_attrcord0.xy - clipDist * m_cordStep.xy; + m_cord1.xy = m_attrcord1.xy - clipDist * m_cordStep.zw; + + m_colour = m_attrcol; +} |