Improve rendering with OpenGL 1.1, removing the visible seams at the cost of slight distortions at high zoom levels.

Originally committed to SVN as r3714.
This commit is contained in:
Thomas Goyne 2009-10-14 20:53:36 +00:00
parent 9ff8f42d7f
commit 3d58608230
2 changed files with 30 additions and 11 deletions

View file

@ -102,7 +102,8 @@ VideoOutGL::VideoOutGL()
textureList(NULL), textureList(NULL),
textureCount(0), textureCount(0),
textureRows(0), textureRows(0),
textureCols(0) textureCols(0),
openGL11(false)
{ } { }
@ -129,6 +130,11 @@ void VideoOutGL::InitTextures(int width, int height, GLenum format, int bpp) {
// Test for rectangular texture support // Test for rectangular texture support
supportsRectangularTextures = TestTexture(maxTextureSize, maxTextureSize >> 1, internalFormat); supportsRectangularTextures = TestTexture(maxTextureSize, maxTextureSize >> 1, internalFormat);
// Check OpenGL version
if (strncmp((const char *)glGetString(GL_VERSION), "1.1", 3) == 0) {
openGL11 = true;
}
} }
// Clean up old textures // Clean up old textures
@ -200,11 +206,10 @@ void VideoOutGL::InitTextures(int width, int height, GLenum format, int bpp) {
if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"glTexParameteri(GL_TEXTURE_MAG_FILTER)", err); if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"glTexParameteri(GL_TEXTURE_MAG_FILTER)", err);
// GL_CLAMP_TO_EDGE was added in OpenGL 1.2, and W7's emulation only supports 1.1 // GL_CLAMP_TO_EDGE was added in OpenGL 1.2, and W7's emulation only supports 1.1
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); GLint mode = openGL11 ? GL_REPEAT : GL_CLAMP_TO_EDGE;
if (glGetError()) glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, mode);
if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"glTexParameteri(GL_TEXTURE_WRAP_S)", err); if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"glTexParameteri(GL_TEXTURE_WRAP_S)", err);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, mode);
if (glGetError()) glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"glTexParameteri(GL_TEXTURE_WRAP_T)", err); if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"glTexParameteri(GL_TEXTURE_WRAP_T)", err);
destX += ti.destW; destX += ti.destW;
@ -249,18 +254,30 @@ void VideoOutGL::DisplayFrame(AegiVideoFrame frame, int sw, int sh) {
if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"glColor4f", err); if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"glColor4f", err);
float top = 0.0f; float top = 0.0f;
float bottom = ti.texH; float bottom = ti.texH;
float left = 0.0f;
float right = 1.0f;
// Slightly stretch the texture under opengl 1.1 to make up for the lack of GL_CLAMP_TO_EDGE
if (openGL11) {
top = 0.01f;
bottom -= 0.01f;
left = 0.01f;
right -= 0.01f;
}
if (frame.flipped) { if (frame.flipped) {
top = ti.texH; float t = top;
bottom = 0.0f; top = bottom;
bottom = t;
} }
glBegin(GL_QUADS); glBegin(GL_QUADS);
glTexCoord2f(0.0f, top); glVertex2f(destX, destY); glTexCoord2f(left, top); glVertex2f(destX, destY);
glTexCoord2f(ti.texW, top); glVertex2f(destX + destW, destY); glTexCoord2f(right, top); glVertex2f(destX + destW, destY);
glTexCoord2f(ti.texW, bottom); glVertex2f(destX + destW, destY + destH); glTexCoord2f(right, bottom); glVertex2f(destX + destW, destY + destH);
glTexCoord2f(0.0f, bottom); glVertex2f(destX, destY + destH); glTexCoord2f(left, bottom); glVertex2f(destX, destY + destH);
glEnd(); glEnd();
if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"GL_QUADS", err); if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"GL_QUADS", err);
} }
glPixelStorei(GL_UNPACK_ROW_LENGTH, 0); glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"glPixelStorei(GL_UNPACK_ROW_LENGTH, default)", err); if (GLenum err = glGetError()) throw VideoOutOpenGLException(L"glPixelStorei(GL_UNPACK_ROW_LENGTH, default)", err);

View file

@ -68,6 +68,8 @@ private:
/// The number of columns of textures /// The number of columns of textures
int textureCols; int textureCols;
bool openGL11;
void InitTextures(int width, int height, GLenum format, int bpp); void InitTextures(int width, int height, GLenum format, int bpp);
VideoOutGL(const VideoOutGL &); VideoOutGL(const VideoOutGL &);