1 /************************************************************************** 2 * 3 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas. 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. 21 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR 22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27 28 29 #include "main/context.h" 30 #include "st_context.h" 31 #include "st_atom.h" 32 #include "pipe/p_context.h" 33 #include "cso_cache/cso_context.h" 34 35 /** 36 * Update the viewport transformation matrix. Depends on: 37 * - viewport pos/size 38 * - depthrange 39 * - window pos/size or FBO size 40 */ 41 static void 42 update_viewport( struct st_context *st ) 43 { 44 struct gl_context *ctx = st->ctx; 45 GLfloat yScale, yBias; 46 47 /* _NEW_BUFFERS 48 */ 49 if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) { 50 /* Drawing to a window. The corresponding gallium surface uses 51 * Y=0=TOP but OpenGL is Y=0=BOTTOM. So we need to invert the viewport. 52 */ 53 yScale = -1; 54 yBias = (GLfloat)ctx->DrawBuffer->Height; 55 } 56 else { 57 /* Drawing to an FBO where Y=0=BOTTOM, like OpenGL - don't invert */ 58 yScale = 1.0; 59 yBias = 0.0; 60 } 61 62 /* _NEW_VIEWPORT 63 */ 64 { 65 GLfloat x = (GLfloat)ctx->Viewport.X; 66 GLfloat y = (GLfloat)ctx->Viewport.Y; 67 GLfloat z = ctx->Viewport.Near; 68 GLfloat half_width = (GLfloat)ctx->Viewport.Width * 0.5f; 69 GLfloat half_height = (GLfloat)ctx->Viewport.Height * 0.5f; 70 GLfloat half_depth = (GLfloat)(ctx->Viewport.Far - ctx->Viewport.Near) * 0.5f; 71 72 st->state.viewport.scale[0] = half_width; 73 st->state.viewport.scale[1] = half_height * yScale; 74 st->state.viewport.scale[2] = half_depth; 75 st->state.viewport.scale[3] = 1.0; 76 77 st->state.viewport.translate[0] = half_width + x; 78 st->state.viewport.translate[1] = (half_height + y) * yScale + yBias; 79 st->state.viewport.translate[2] = half_depth + z; 80 st->state.viewport.translate[3] = 0.0; 81 82 cso_set_viewport(st->cso_context, &st->state.viewport); 83 } 84 } 85 86 87 const struct st_tracked_state st_update_viewport = { 88 "st_update_viewport", /* name */ 89 { /* dirty */ 90 _NEW_BUFFERS | _NEW_VIEWPORT, /* mesa */ 91 0, /* st */ 92 }, 93 update_viewport /* update */ 94 }; 95
