2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 #include "main/glheader.h"
26 #include "main/colormac.h"
27 #include "main/condrender.h"
28 #include "main/macros.h"
29 #include "main/imports.h"
30 #include "main/mtypes.h"
33 #include "s_context.h"
35 #include "s_masking.h"
36 #include "s_stencil.h"
40 * Clear the color buffer when glColorMask is in effect.
43 clear_rgba_buffer_with_masking(struct gl_context *ctx, struct gl_renderbuffer *rb,
46 const GLint x = ctx->DrawBuffer->_Xmin;
47 const GLint y = ctx->DrawBuffer->_Ymin;
48 const GLint height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
49 const GLint width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
55 /* Initialize color span with clear color */
56 /* XXX optimize for clearcolor == black/zero (bzero) */
57 INIT_SPAN(span, GL_BITMAP);
59 span.arrayMask = SPAN_RGBA;
60 span.array->ChanType = rb->DataType;
61 if (span.array->ChanType == GL_UNSIGNED_BYTE) {
62 GLubyte clearColor[4];
63 UNCLAMPED_FLOAT_TO_UBYTE(clearColor[RCOMP], ctx->Color.ClearColor[0]);
64 UNCLAMPED_FLOAT_TO_UBYTE(clearColor[GCOMP], ctx->Color.ClearColor[1]);
65 UNCLAMPED_FLOAT_TO_UBYTE(clearColor[BCOMP], ctx->Color.ClearColor[2]);
66 UNCLAMPED_FLOAT_TO_UBYTE(clearColor[ACOMP], ctx->Color.ClearColor[3]);
67 for (i = 0; i < width; i++) {
68 COPY_4UBV(span.array->rgba[i], clearColor);
71 else if (span.array->ChanType == GL_UNSIGNED_SHORT) {
72 GLushort clearColor[4];
73 UNCLAMPED_FLOAT_TO_USHORT(clearColor[RCOMP], ctx->Color.ClearColor[0]);
74 UNCLAMPED_FLOAT_TO_USHORT(clearColor[GCOMP], ctx->Color.ClearColor[1]);
75 UNCLAMPED_FLOAT_TO_USHORT(clearColor[BCOMP], ctx->Color.ClearColor[2]);
76 UNCLAMPED_FLOAT_TO_USHORT(clearColor[ACOMP], ctx->Color.ClearColor[3]);
77 for (i = 0; i < width; i++) {
78 COPY_4V_CAST(span.array->rgba[i], clearColor, GLchan);
82 ASSERT(span.array->ChanType == GL_FLOAT);
83 for (i = 0; i < width; i++) {
84 CLAMPED_FLOAT_TO_CHAN(span.array->rgba[i][0], ctx->Color.ClearColor[0]);
85 CLAMPED_FLOAT_TO_CHAN(span.array->rgba[i][1], ctx->Color.ClearColor[1]);
86 CLAMPED_FLOAT_TO_CHAN(span.array->rgba[i][2], ctx->Color.ClearColor[2]);
87 CLAMPED_FLOAT_TO_CHAN(span.array->rgba[i][3], ctx->Color.ClearColor[3]);
91 /* Note that masking will change the color values, but only the
92 * channels for which the write mask is GL_FALSE. The channels
93 * which which are write-enabled won't get modified.
95 for (i = 0; i < height; i++) {
98 _swrast_mask_rgba_span(ctx, rb, &span, buf);
99 /* write masked row */
100 rb->PutRow(ctx, rb, width, x, y + i, span.array->rgba, NULL);
106 * Clear an rgba color buffer without channel masking.
109 clear_rgba_buffer(struct gl_context *ctx, struct gl_renderbuffer *rb, GLuint buf)
111 const GLint x = ctx->DrawBuffer->_Xmin;
112 const GLint y = ctx->DrawBuffer->_Ymin;
113 const GLint height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
114 const GLint width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
120 ASSERT(ctx->Color.ColorMask[buf][0] &&
121 ctx->Color.ColorMask[buf][1] &&
122 ctx->Color.ColorMask[buf][2] &&
123 ctx->Color.ColorMask[buf][3]);
125 ASSERT(rb->PutMonoRow);
127 switch (rb->DataType) {
128 case GL_UNSIGNED_BYTE:
129 UNCLAMPED_FLOAT_TO_UBYTE(clear8[0], ctx->Color.ClearColor[0]);
130 UNCLAMPED_FLOAT_TO_UBYTE(clear8[1], ctx->Color.ClearColor[1]);
131 UNCLAMPED_FLOAT_TO_UBYTE(clear8[2], ctx->Color.ClearColor[2]);
132 UNCLAMPED_FLOAT_TO_UBYTE(clear8[3], ctx->Color.ClearColor[3]);
135 case GL_UNSIGNED_SHORT:
136 UNCLAMPED_FLOAT_TO_USHORT(clear16[0], ctx->Color.ClearColor[0]);
137 UNCLAMPED_FLOAT_TO_USHORT(clear16[1], ctx->Color.ClearColor[1]);
138 UNCLAMPED_FLOAT_TO_USHORT(clear16[2], ctx->Color.ClearColor[2]);
139 UNCLAMPED_FLOAT_TO_USHORT(clear16[3], ctx->Color.ClearColor[3]);
143 clearVal = ctx->Color.ClearColor;
146 _mesa_problem(ctx, "Bad rb DataType in clear_color_buffer");
150 for (i = 0; i < height; i++) {
151 rb->PutMonoRow(ctx, rb, width, x, y + i, clearVal, NULL);
157 * Clear the front/back/left/right/aux color buffers.
158 * This function is usually only called if the device driver can't
159 * clear its own color buffers for some reason (such as with masking).
162 clear_color_buffers(struct gl_context *ctx)
166 for (buf = 0; buf < ctx->DrawBuffer->_NumColorDrawBuffers; buf++) {
167 struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[buf];
169 /* If this is an ES2 context or GL_ARB_ES2_compatibility is supported,
170 * the framebuffer can be complete with some attachments be missing. In
171 * this case the _ColorDrawBuffers pointer will be NULL.
176 if (ctx->Color.ColorMask[buf][0] == 0 ||
177 ctx->Color.ColorMask[buf][1] == 0 ||
178 ctx->Color.ColorMask[buf][2] == 0 ||
179 ctx->Color.ColorMask[buf][3] == 0) {
180 clear_rgba_buffer_with_masking(ctx, rb, buf);
183 clear_rgba_buffer(ctx, rb, buf);
190 * Called via the device driver's ctx->Driver.Clear() function if the
191 * device driver can't clear one or more of the buffers itself.
192 * \param buffers bitfield of BUFFER_BIT_* values indicating which
193 * renderbuffers are to be cleared.
194 * \param all if GL_TRUE, clear whole buffer, else clear specified region.
197 _swrast_Clear(struct gl_context *ctx, GLbitfield buffers)
201 const GLbitfield legalBits =
202 BUFFER_BIT_FRONT_LEFT |
203 BUFFER_BIT_FRONT_RIGHT |
204 BUFFER_BIT_BACK_LEFT |
205 BUFFER_BIT_BACK_RIGHT |
210 assert((buffers & (~legalBits)) == 0);
214 if (!_mesa_check_conditional_render(ctx))
215 return; /* don't clear */
217 swrast_render_start(ctx);
219 /* do software clearing here */
221 if ((buffers & BUFFER_BITS_COLOR)
222 && (ctx->DrawBuffer->_NumColorDrawBuffers > 0)) {
223 clear_color_buffers(ctx);
225 if (buffers & BUFFER_BIT_DEPTH) {
226 _swrast_clear_depth_buffer(ctx, ctx->DrawBuffer->_DepthBuffer);
228 if (buffers & BUFFER_BIT_ACCUM) {
229 _swrast_clear_accum_buffer(ctx,
230 ctx->DrawBuffer->Attachment[BUFFER_ACCUM].Renderbuffer);
232 if (buffers & BUFFER_BIT_STENCIL) {
233 _swrast_clear_stencil_buffer(ctx, ctx->DrawBuffer->_StencilBuffer);
237 swrast_render_finish(ctx);